@article {923, title = {Alternative genomic diagnoses for individuals with a clinical diagnosis of Dubowitz syndrome.}, journal = {Am J Med Genet A}, volume = {185}, year = {2021}, month = {2021 01}, pages = {119-133}, abstract = {

Dubowitz syndrome (DubS) is considered a recognizable syndrome characterized by a distinctive facial appearance and deficits in growth and development. There have been over 200 individuals reported with Dubowitz or a "Dubowitz-like" condition, although no single gene has been implicated as responsible for its cause. We have performed exome (ES) or genome sequencing (GS) for 31 individuals clinically diagnosed with DubS. After genome-wide sequencing, rare variant filtering and computational and Mendelian genomic analyses, a presumptive molecular diagnosis was made in 13/27 (48\%) families. The molecular diagnoses included biallelic variants in SKIV2L, SLC35C1, BRCA1, NSUN2; de novo variants in ARID1B, ARID1A, CREBBP, POGZ, TAF1, HDAC8, and copy-number variation at1p36.11(ARID1A), 8q22.2(VPS13B), Xp22, and Xq13(HDAC8). Variants of unknown significance in known disease genes, and also in genes of uncertain significance, were observed in 7/27 (26\%) additional families. Only one gene, HDAC8, could explain the phenotype in more than one family (N = 2). All but two of the genomic diagnoses were for genes discovered, or for conditions recognized, since the introduction of next-generation sequencing. Overall, the DubS-like clinical phenotype is associated with extensive locus heterogeneity and the molecular diagnoses made are for emerging clinical conditions sharing characteristic features that overlap the DubS phenotype.

}, issn = {1552-4833}, doi = {10.1002/ajmg.a.61926}, author = {Dyment, David A and O{\textquoteright}Donnell-Luria, Anne and Agrawal, Pankaj B and Coban Akdemir, Zeynep and Aleck, Kyrieckos A and Antaki, Danny and Al Sharhan, Hind and Au, Ping-Yee B and Aydin, Hatip and Beggs, Alan H and Bilguvar, Kaya and Boerwinkle, Eric and Brand, Harrison and Brownstein, Catherine A and Buyske, Steve and Chodirker, Bernard and Choi, Jungmin and Chudley, Albert E and Clericuzio, Carol L and Cox, Gerald F and Curry, Cynthia and de Boer, Elke and de Vries, Bert B A and Dunn, Kathryn and Dutmer, Cullen M and England, Eleina M and Fahrner, Jill A and Geckinli, Bilgen B and Genetti, Casie A and Gezdirici, Alper and Gibson, William T and Gleeson, Joseph G and Greenberg, Cheryl R and Hall, April and Hamosh, Ada and Hartley, Taila and Jhangiani, Shalini N and Karaca, Ender and Kernohan, Kristin and Lauzon, Julie L and Lewis, M E Suzanne and Lowry, R Brian and L{\'o}pez-Gir{\'a}ldez, Francesc and Matise, Tara C and McEvoy-Venneri, Jennifer and McInnes, Brenda and Mhanni, Aziz and Garcia Minaur, Sixto and Moilanen, Jukka and Nguyen, An and Nowaczyk, Malgorzata J M and Posey, Jennifer E and {\~O}unap, Katrin and Pehlivan, Davut and Pajusalu, Sander and Penney, Lynette S and Poterba, Timothy and Prontera, Paolo and Doriqui, Maria Juliana Rodovalho and Sawyer, Sarah L and Sobreira, Nara and Stanley, Valentina and Torun, Deniz and Wargowski, David and Witmer, P Dane and Wong, Isaac and Xing, Jinchuan and Zaki, MAH S and Zhang, Yeting and Boycott, Kym M and Bamshad, Michael J and Nickerson, Deborah A and Blue, Elizabeth E and Innes, A Micheil} } @article {891, title = {Germline mutation in : a heterogeneous, multi-systemic developmental disorder characterized by transcriptional dysregulation.}, journal = {HGG Adv}, volume = {2}, year = {2021}, month = {2021 Jan 14}, abstract = {

germline variation in was recently reported to associate with a neurodevelopmental disorder. We report twelve individuals harboring putatively pathogenic or inherited variants in , detail their phenotypes, and map all known variants to the domain structure of and crystal structure of RNA polymerase II. Affected individuals were ascertained from a local data lake, pediatric genetics clinic, and an online community of families of affected individuals. These include six affected by missense variants (including one previously reported individual), four clinical laboratory samples affected by missense variation with unknown inheritance-with yeast functional assays further supporting altered function-one affected by a in-frame deletion, and one affected by a C-terminal frameshift variant inherited from a largely asymptomatic mother. Recurrently observed phenotypes include ataxia, joint hypermobility, short stature, skin abnormalities, congenital cardiac abnormalities, immune system abnormalities, hip dysplasia, and short Achilles tendons. We report a significantly higher occurrence of epilepsy (8/12, 66.7\%) than previously reported (3/15, 20\%) (p value = 0.014196; chi-square test) and a lower occurrence of hypotonia (8/12, 66.7\%) than previously reported (14/15, 93.3\%) (p value = 0.076309). -related developmental disorders likely represent a spectrum of related, multi-systemic developmental disorders, driven by distinct mechanisms, converging at a single locus.

}, issn = {2666-2477}, doi = {10.1016/j.xhgg.2020.100014}, author = {Hansen, Adam W and Arora, Payal and Khayat, Michael M and Smith, Leah J and Lewis, Andrea M and Rossetti, Linda Z and Jayaseelan, Joy and Cristian, Ingrid and Haynes, Devon and DiTroia, Stephanie and Meeks, Naomi and Delgado, Mauricio R and Rosenfeld, Jill A and Pais, Lynn and White, Susan M and Meng, Qingchang and Pehlivan, Davut and Liu, Pengfei and Gingras, Marie-Claude and Wangler, Michael F and Muzny, Donna M and Lupski, James R and Kaplan, Craig D and Gibbs, Richard A} } @article {941, title = {MED27 Variants Cause Developmental Delay, Dystonia, and Cerebellar Hypoplasia.}, journal = {Ann Neurol}, volume = {89}, year = {2021}, month = {2021 04}, pages = {828-833}, abstract = {

The Mediator multiprotein complex functions as a regulator of RNA polymerase II-catalyzed gene transcription. In this study, exome sequencing detected biallelic putative disease-causing variants in MED27, encoding Mediator complex subunit 27, in 16 patients from 11 families with a novel neurodevelopmental syndrome. Patient phenotypes are highly homogeneous, including global developmental delay, intellectual disability, axial hypotonia with distal spasticity, dystonic movements, and cerebellar hypoplasia. Seizures and cataracts were noted in severely affected individuals. Identification of multiple patients with biallelic MED27 variants supports the critical role of MED27 in normal human neural development, particularly for the cerebellum. ANN NEUROL 2021;89:828-833.

}, keywords = {Adolescent, Adult, Amino Acid Sequence, Cataract, Cerebellum, Child, Child, Preschool, Developmental Disabilities, Dystonia, Epilepsy, Genetic Variation, Humans, Infant, Mediator Complex, Nervous System Malformations, Phenotype, Whole Exome Sequencing}, issn = {1531-8249}, doi = {10.1002/ana.26019}, author = {Meng, Linyan and Isohanni, Pirjo and Shao, Yunru and GrAHm, Brett H and Hickey, Scott E and Brooks, Stephanie and Suomalainen, Anu and Joset, Pascal and Steindl, Katharina and Rauch, Anita and Hackenberg, Annette and High, Frances A and Armstrong-Javors, Amy and Mencacci, Niccol{\`o} E and Gonz{\`a}lez-Latapi, Paulina and Kamel, Walaa A and Al-Hashel, Jasem Y and Bustos, Bernab{\'e} I and Hernandez, Alejandro V and Krainc, Dimitri and Lubbe, Steven J and Van Esch, Hilde and De Luca, Chiara and Ballon, Katleen and Ravelli, Claudia and Burglen, Lydie and Qebibo, Leila and Calame, Daniel G and Mitani, Tadahiro and Marafi, Dana and Pehlivan, Davut and Saadi, Nebal W and Sahin, Yavuz and Maroofian, Reza and Efthymiou, Stephanie and Houlden, Henry and Maqbool, Shazia and Rahman, Fatima and Gu, Shen and Posey, Jennifer E and Lupski, James R and Hunter, Jill V and Wangler, Michael F and Carroll, Christopher J and Yang, Yaping} } @article {1014, title = {Neurodevelopmental disorder in an Egyptian family with a biallelic ALKBH8 variant.}, journal = {Am J Med Genet A}, volume = {185}, year = {2021}, month = {2021 04}, pages = {1288-1293}, abstract = {

Alkylated DNA repair protein AlkB homolog 8 (ALKBH8) is a member of the AlkB family of dioxygenases. ALKBH8 is a methyltransferase of the highly variable wobble nucleoside position in the anticodon loop of tRNA and thus plays a critical role in tRNA modification by preserving codon recognition and preventing errors in amino acid incorporation during translation. Moreover, its activity catalyzes uridine modifications that are proposed to be critical for accurate protein translation. Previously, two distinct homozygous truncating variants in the final exon of ALKBH8 were described in two unrelated large Saudi Arabian kindreds with intellectual developmental disorder and autosomal recessive 71 (MRT71) syndrome (MIM$\#$ 618504). Here, we report a third family-of Egyptian descent-harboring a novel homozygous frame-shift variant in the last exon of ALKBH8. Two affected siblings in this family exhibit global developmental delay and intellectual disability as shared characteristic features of MRT71 syndrome, and we further characterize their observed dysmorphic features and brain MRI findings. This description of a third family with a truncating ALKBH8 variant from a distinct population broadens the phenotypic and genotypic spectrum of MRT71 syndrome, affirms that perturbations in tRNA biogenesis can contribute to neurogenetic disease traits, and firmly establishes ALKBH8 as a novel neurodevelopmental disease gene.

}, issn = {1552-4833}, doi = {10.1002/ajmg.a.62100}, author = {Saad, Ahmed K and Marafi, Dana and Mitani, Tadahiro and Du, Haowei and Rafat, Karima and Fatih, Jawid M and Jhangiani, Shalini N and Coban-Akdemir, Zeynep and Gibbs, Richard A and Pehlivan, Davut and Hunter, Jill V and Posey, Jennifer E and Zaki, MAH S and Lupski, James R} } @article {1015, title = {A novel homozygous SLC13A5 whole-gene deletion generated by Alu/Alu-mediated rearrangement in an Iraqi family with epileptic encephalopathy.}, journal = {Am J Med Genet A}, year = {2021}, month = {2021 Apr 02}, abstract = {

Biallelic loss-of-function (LoF) of SLC13A5 (solute carrier family 13, member 5) induced deficiency in sodium/citrate transporter (NaCT) causes autosomal recessive developmental epileptic encephalopathy 25 with hypoplastic amelogenesis imperfecta (DEE25; MIM $\#$615905). Many pathogenic SLC13A5 single nucleotide variants (SNVs) and small indels have been described; however, no cases with copy number variants (CNVs) have been sufficiently investigated. We describe a consanguineous Iraqi family harboring an 88.5 kb homozygous deletion including SLC13A5 in Chr17p13.1. The three affected male siblings exhibit neonatal-onset epilepsy with fever-sensitivity, recurrent status epilepticus, global developmental delay/intellectual disability (GDD/ID), and other variable neurological findings as shared phenotypical features of DEE25. Two of the three affected subjects exhibit hypoplastic amelogenesis imperfecta (AI), while the proband shows no evidence of dental abnormalities or AI at 2 years of age with apparently unaffected primary dentition. Characterization of the genomic architecture at this locus revealed evidence for genomic instability generated by an Alu/Alu-mediated rearrangement; confirmed by break-point junction Sanger sequencing. This multiplex family from a distinct population elucidates the phenotypic consequence of complete LoF of SLC13A5 and illustrates the importance of read-depth-based CNV detection in comprehensive exome sequencing analysis to solve cases that otherwise remain molecularly unsolved.

}, issn = {1552-4833}, doi = {10.1002/ajmg.a.62192}, author = {Duan, Ruizhi and Saadi, Nebal Waill and Grochowski, Christopher M and Bhadila, Ghalia and Faridoun, Afnan and Mitani, Tadahiro and Du, Haowei and Fatih, Jawid M and Jhangiani, Shalini N and Akdemir, Zeynep C and Gibbs, Richard A and Pehlivan, Davut and Posey, Jennifer E and Marafi, Dana and Lupski, James R} } @article {1026, title = {Two novel bi-allelic KDELR2 missense variants cause osteogenesis imperfecta with neurodevelopmental features.}, journal = {Am J Med Genet A}, year = {2021}, month = {2021 May 08}, issn = {1552-4833}, doi = {10.1002/ajmg.a.62221}, author = {Efthymiou, Stephanie and Herman, Isabella and Rahman, Fatima and Anwar, Najwa and Maroofian, Reza and Yip, Janice and Mitani, Tadahiro and Calame, Daniel G and Hunter, Jill V and Sutton, V Reid and Yilmaz Gulec, Elif and Duan, Ruizhi and Fatih, Jawid M and Marafi, Dana and Pehlivan, Davut and Jhangiani, Shalini N and Gibbs, Richard A and Posey, Jennifer E and Maqbool, Shazia and Lupski, James R and Houlden, Henry} } @article {758, title = {Biallelic GRM7 variants cause epilepsy, microcephaly, and cerebral atrophy.}, journal = {Ann Clin Transl Neurol}, volume = {7}, year = {2020}, month = {2020 05}, pages = {610-627}, abstract = {

OBJECTIVE: Defects in ion channels and neurotransmitter receptors are implicated in developmental and epileptic encephalopathy (DEE). Metabotropic glutamate receptor 7 (mGluR7), encoded by GRM7, is a presynaptic G-protein-coupled glutamate receptor critical for synaptic transmission. We previously proposed GRM7 as a candidate disease gene in two families with neurodevelopmental disorders (NDDs). One additional family has been published since. Here, we describe three additional families with GRM7 biallelic variants and deeply characterize the associated clinical neurological and electrophysiological phenotype and molecular data in 11 affected individuals from six unrelated families.

METHODS: Exome sequencing and family-based rare variant analyses on a cohort of 220 consanguineous families with NDDs revealed three families with GRM7 biallelic variants; three additional families were identified through literature search and collaboration with a clinical molecular laboratory.

RESULTS: We compared the observed clinical features and variants of 11 affected individuals from the six unrelated families. Identified novel deleterious variants included two homozygous missense variants (c.2671G>A:p.Glu891Lys and c.1973G>A:p.Arg685Gln) and one homozygous stop-gain variant (c.1975C>T:p.Arg659Ter). Developmental delay, neonatal- or infantile-onset epilepsy, and microcephaly were universal. Three individuals had hypothalamic-pituitary-axis dysfunction without pituitary structural abnormality. Neuroimaging showed cerebral atrophy and hypomyelination in a majority of cases. Two siblings demonstrated progressive loss of myelination by 2~years in both and an acquired microcephaly pattern in one. Five individuals died in early or late childhood.

CONCLUSION: Detailed clinical characterization of 11 individuals from six unrelated families demonstrates that rare biallelic GRM7 pathogenic variants can cause DEEs, microcephaly, hypomyelination, and cerebral atrophy.

}, keywords = {Adolescent, Alleles, Atrophy, Child, Child, Preschool, Cohort Studies, Consanguinity, Epilepsy, Female, Humans, Infant, Male, Microcephaly, Neurodevelopmental Disorders, Pedigree, Phenotype, Receptors, Metabotropic Glutamate, Whole Exome Sequencing}, issn = {2328-9503}, doi = {10.1002/acn3.51003}, author = {Marafi, Dana and Mitani, Tadahiro and Isikay, Sedat and Hertecant, Jozef and Almannai, Mohammed and Manickam, Kandamurugu and Abou Jamra, Rami and El-Hattab, Ayman W and Rajah, Jaishen and Fatih, Jawid M and Du, Haowei and Karaca, Ender and Bayram, Yavuz and Punetha, Jaya and Rosenfeld, Jill A and Jhangiani, Shalini N and Boerwinkle, Eric and Akdemir, Zeynep C and Erdin, Serkan and Hunter, Jill V and Gibbs, Richard A and Pehlivan, Davut and Posey, Jennifer E and Lupski, James R} } @article {945, title = {Biallelic in-frame deletion in TRAPPC4 in a family with developmental delay and cerebellar atrophy.}, journal = {Brain}, volume = {143}, year = {2020}, month = {2020 10 01}, pages = {e83}, keywords = {Atrophy, Cerebellar Diseases, Humans, Intellectual Disability, Sequence Deletion}, issn = {1460-2156}, doi = {10.1093/brain/awaa256}, author = {Saad, Ahmed K and Marafi, Dana and Mitani, Tadahiro and Jolly, Angad and Du, Haowei and Elbendary, Hasnaa M and Jhangiani, Shalini N and Akdemir, Zeynep C and Gibbs, Richard A and Hunter, Jill V and Carvalho, Claudia M B C and Pehlivan, Davut and Posey, Jennifer E and Zaki, MAH S and Lupski, James R} } @article {738, title = {Deficiencies in vesicular transport mediated by TRAPPC4 are associated with severe syndromic intellectual disability.}, journal = {Brain}, volume = {143}, year = {2020}, month = {2020 01 01}, pages = {112-130}, abstract = {

The conserved transport protein particle (TRAPP) complexes regulate key trafficking events and are required for autophagy. TRAPPC4, like its yeast Trs23 orthologue, is a core component of the TRAPP complexes and one of the essential subunits for guanine nucleotide exchange factor activity for Rab1 GTPase. Pathogenic variants in specific TRAPP subunits are associated with neurological disorders. We undertook exome sequencing in three unrelated families of Caucasian, Turkish and French-Canadian ethnicities with seven affected children that showed features of early-onset seizures, developmental delay, microcephaly, sensorineural deafness, spastic quadriparesis and progressive cortical and cerebellar atrophy in an effort to determine the genetic aetiology underlying neurodevelopmental disorders. All seven affected subjects shared the same identical rare, homozygous, potentially pathogenic variant in a non-canonical, well-conserved splice site within TRAPPC4 (hg19:chr11:g.118890966A>G; TRAPPC4: NM_016146.5; c.454+3A>G). Single nucleotide polymorphism array analysis revealed there was no haplotype shared between the tested Turkish and Caucasian families suggestive of a variant hotspot region rather than a founder effect. In silico analysis predicted the variant to cause aberrant splicing. Consistent with this, experimental evidence showed both a reduction in full-length transcript levels and an increase in levels of a shorter transcript missing exon 3, suggestive of an incompletely penetrant splice defect. TRAPPC4 protein levels were significantly reduced whilst levels of other TRAPP complex subunits remained unaffected. Native polyacrylamide gel electrophoresis and size exclusion chromatography demonstrated a defect in TRAPP complex assembly and/or stability. Intracellular trafficking through the Golgi using the marker protein VSVG-GFP-ts045 demonstrated significantly delayed entry into and exit from the Golgi in fibroblasts derived from one of the affected subjects. Lentiviral expression of wild-type TRAPPC4 in these fibroblasts restored trafficking, suggesting that the trafficking defect was due to reduced TRAPPC4 levels. Consistent with the recent association of the TRAPP complex with autophagy, we found that the fibroblasts had a basal autophagy defect and a delay in autophagic flux, possibly due to unsealed autophagosomes. These results were validated using a yeast trs23 temperature sensitive variant that exhibits constitutive and stress-induced autophagic defects at permissive temperature and a secretory defect at restrictive temperature. In summary we provide strong evidence for pathogenicity of this variant in a member of the core TRAPP subunit, TRAPPC4 that associates with vesicular trafficking and autophagy defects. This is the first report of a TRAPPC4 variant, and our findings add to the growing number of TRAPP-associated neurological disorders.

}, keywords = {Atrophy, Autophagy, Cerebellum, Cerebral Cortex, Child, Child, Preschool, Craniofacial Abnormalities, Deafness, Developmental Disabilities, Epilepsy, Female, Fibroblasts, Hearing Loss, Sensorineural, Humans, Infant, Infant, Newborn, Intellectual Disability, Male, Microcephaly, Microscopy, Fluorescence, Muscle Spasticity, Nerve Tissue Proteins, Neurodevelopmental Disorders, Pedigree, Quadriplegia, RNA Splice Sites, Syndrome, Vesicular Transport Proteins}, issn = {1460-2156}, doi = {10.1093/brain/awz374}, author = {Van Bergen, Nicole J and Guo, Yiran and Al-Deri, Noraldin and Lipatova, Zhanna and Stanga, Daniela and Zhao, Sarah and Murtazina, Rakhilya and Gyurkovska, Valeriya and Pehlivan, Davut and Mitani, Tadahiro and Gezdirici, Alper and Antony, Jayne and Collins, Felicity and Willis, Mary J H and Coban Akdemir, Zeynep H and Liu, Pengfei and Punetha, Jaya and Hunter, Jill V and Jhangiani, Shalini N and Fatih, Jawid M and Rosenfeld, Jill A and Posey, Jennifer E and Gibbs, Richard A and Karaca, Ender and Massey, Sean and Ranasinghe, Thisara G and Sleiman, Patrick and Troedson, Chris and Lupski, James R and Sacher, Michael and Segev, Nava and Hakonarson, Hakon and Christodoulou, John} } @article {777, title = {Functional biology of the Steel syndrome founder allele and evidence for clan genomics derivation of COL27A1 pathogenic alleles worldwide.}, journal = {Eur J Hum Genet}, volume = {28}, year = {2020}, month = {2020 09}, pages = {1243-1264}, abstract = {

Previously we reported the identification of a homozygous COL27A1 (c.2089G>C; p.Gly697Arg) missense variant and proposed it as a founder allele in Puerto Rico segregating with Steel syndrome (STLS, MIM $\#$615155); a rare osteochondrodysplasia characterized by short stature, congenital bilateral hip dysplasia, carpal coalitions, and scoliosis. We now report segregation of this variant in five probands from the initial clinical report defining the syndrome and an additional family of Puerto Rican descent with multiple affected adult individuals. We modeled the orthologous variant in murine Col27a1 and found it recapitulates some of the major Steel syndrome associated skeletal features including reduced body length, scoliosis, and a more rounded skull shape. Characterization of the in vivo murine model shows abnormal collagen deposition in the extracellular matrix and disorganization of the proliferative zone of the growth plate. We report additional COL27A1 pathogenic variant alleles identified in unrelated consanguineous Turkish kindreds suggesting Clan Genomics and identity-by-descent homozygosity contributing to disease in this population. The hypothesis that carrier states for this autosomal recessive osteochondrodysplasia may contribute to common complex traits is further explored in a large clinical population cohort. Our findings augment our understanding of COL27A1 biology and its role in skeletal development; and expand the functional allelic architecture in this gene underlying both rare and common disease phenotypes.

}, keywords = {Abnormalities, Multiple, Adolescent, Animals, Bone Development, Child, Child, Preschool, Consanguinity, Extracellular Matrix, Female, Fibrillar Collagens, Founder Effect, Gene Frequency, Hip Dislocation, Homozygote, Humans, Male, Mice, Mice, Inbred C57BL, Mutation, Pedigree, Scoliosis, Syndrome}, issn = {1476-5438}, doi = {10.1038/s41431-020-0632-x}, author = {Gonzaga-Jauregui, Claudia and Yesil, G{\"o}zde and Nistala, Harikiran and Gezdirici, Alper and Bayram, Yavuz and Nannuru, Kalyan C and Pehlivan, Davut and Yuan, Bo and Jimenez, Johanna and Sahin, Yavuz and Paine, Ingrid S and Akdemir, Zeynep Coban and Rajamani, Saathyaki and Staples, Jeffrey and Dronzek, John and Howell, Kristen and Fatih, Jawid M and Smaldone, Silvia and Schlesinger, Alan E and Ram{\'\i}rez, Norman and Cornier, Alberto S and Kelly, Melissa A and Haber, Robert and Chim, Shek Man and Nieman, Kristy and Wu, Nan and Walls, Johnathon and Poueymirou, William and Siao, Chia-Jen and Sutton, V Reid and Williams, Marc S and Posey, Jennifer E and Gibbs, Richard A and Carlo, Simon and Tegay, David H and Economides, Aris N and Lupski, James R} } @article {954, title = {Human and mouse studies establish TBX6 in Mendelian CAKUT and as a potential driver of kidney defects associated with the 16p11.2 microdeletion syndrome.}, journal = {Kidney Int}, volume = {98}, year = {2020}, month = {2020 10}, pages = {1020-1030}, abstract = {

Congenital anomalies of the kidney and urinary tract (CAKUTs) are the most common cause of chronic kidney disease in children. Human 16p11.2 deletions have been associated with CAKUT, but the responsible molecular mechanism remains to be illuminated. To explore this, we investigated 102 carriers of 16p11.2 deletion from multi-center cohorts, among which we retrospectively ascertained kidney morphologic and functional data from 37 individuals (12 Chinese and 25 Caucasian/Hispanic). Significantly higher CAKUT rates were observed in 16p11.2 deletion carriers (about 25\% in Chinese and 16\% in Caucasian/Hispanic) than those found in the non-clinically ascertained general populations (about 1/1000 found at autopsy). Furthermore, we identified seven additional individuals with heterozygous loss-of-function variants in TBX6, a gene that maps to the 16p11.2 region. Four of these seven cases showed obvious CAKUT. To further investigate the role of TBX6 in kidney development, we engineered mice with mutated Tbx6 alleles. The Tbx6 heterozygous null (i.e., loss-of-function) mutant (Tbx6) resulted in 13\% solitary kidneys. Remarkably, this incidence increased to 29\% in a compound heterozygous model (Tbx6) that reduced Tbx6 gene dosage to below haploinsufficiency, by combining the null allele with a novel mild hypomorphic allele (mh). Renal hypoplasia was also frequently observed in these Tbx6-mutated mouse models. Thus, our findings in patients and mice establish TBX6 as a novel gene involved in CAKUT and its gene dosage insufficiency as a potential driver for kidney defects observed in the 16p11.2 microdeletion syndrome.

}, issn = {1523-1755}, doi = {10.1016/j.kint.2020.04.045}, author = {Yang, Nan and Wu, Nan and Dong, Shuangshuang and Zhang, Ling and Zhao, Yanxue and Chen, Weisheng and Du, Renqian and Song, Chengcheng and Ren, Xiaojun and Liu, Jiaqi and Pehlivan, Davut and Liu, Zhenlei and Rao, Jia and Wang, Chunyan and Zhao, Sen and Breman, Amy M and Xue, Huadan and Sun, Hao and Shen, Jianxiong and Zhang, Shuyang and Posey, Jennifer E and Xu, Hong and Jin, Li and Zhang, Jianguo and Liu, Pengfei and Sanna-Cherchi, Simone and Qiu, Guixing and Wu, Zhihong and Lupski, James R and Zhang, Feng} } @article {799, title = {NEMF mutations that impair ribosome-associated quality control are associated with neuromuscular disease.}, journal = {Nat Commun}, volume = {11}, year = {2020}, month = {2020 09 15}, pages = {4625}, abstract = {

A hallmark of neurodegeneration is defective protein quality control. The E3 ligase Listerin (LTN1/Ltn1) acts in a specialized protein quality control pathway-Ribosome-associated Quality Control (RQC)-by mediating proteolytic targeting of incomplete polypeptides produced by ribosome stalling, and Ltn1 mutation leads to neurodegeneration in mice. Whether neurodegeneration results from defective RQC and whether defective RQC contributes to human disease have remained unknown. Here we show that three independently-generated mouse models with mutations in a different component of the RQC complex, NEMF/Rqc2, develop progressive motor neuron degeneration. Equivalent mutations in yeast Rqc2 selectively interfere with its ability to modify aberrant translation products with C-terminal tails which assist with RQC-mediated protein degradation, suggesting a pathomechanism. Finally, we identify NEMF mutations expected to interfere with function in patients from seven families presenting juvenile neuromuscular disease. These uncover NEMF{\textquoteright}s role in translational homeostasis in the nervous system and implicate RQC dysfunction in causing neurodegeneration.

}, keywords = {Amino Acid Sequence, Animals, Female, Humans, Male, Mice, Mice, Knockout, Mutation, Neuromuscular Diseases, Proteolysis, Ribosomes, RNA-Binding Proteins, Saccharomyces cerevisiae, Saccharomyces cerevisiae Proteins, Sequence Alignment}, issn = {2041-1723}, doi = {10.1038/s41467-020-18327-6}, author = {Martin, Paige B and Kigoshi-Tansho, Yu and Sher, Roger B and Ravenscroft, Gianina and Stauffer, Jennifer E and Kumar, Rajesh and Yonashiro, Ryo and M{\"u}ller, Tina and Griffith, Christopher and Allen, William and Pehlivan, Davut and Harel, Tamar and Zenker, Martin and Howting, Denise and Schanze, Denny and Faqeih, Eissa A and Almontashiri, Naif A M and Maroofian, Reza and Houlden, Henry and Mazaheri, Neda and Galehdari, Hamid and Douglas, Ganka and Posey, Jennifer E and Ryan, Monique and Lupski, James R and Laing, Nigel G and Joazeiro, Claudio A P and Cox, Gregory A} } @article {854, title = {Phenotypic expansion in KIF1A-related dominant disorders: A description of novel variants and review of published cases.}, journal = {Hum Mutat}, volume = {41}, year = {2020}, month = {2020 12}, pages = {2094-2104}, abstract = {

KIF1A is a molecular motor for membrane-bound cargo important to the development and survival of sensory neurons. KIF1A dysfunction has been associated with several Mendelian disorders with a spectrum of overlapping phenotypes, ranging from spastic paraplegia to intellectual disability. We present a novel pathogenic in-frame deletion in the KIF1A molecular motor domain inherited by two affected siblings from an unaffected mother with apparent germline mosaicism. We identified eight additional cases with heterozygous, pathogenic KIF1A variants ascertained from a local data lake. Our data provide evidence for the expansion of KIF1A-associated phenotypes to include hip subluxation and dystonia~as well as phenotypes observed in only a single case: gelastic cataplexy, coxa valga, and double collecting system. We review the literature and suggest that KIF1A dysfunction is better understood as a single neuromuscular disorder with variable involvement of other organ systems than a set of discrete disorders converging at a single locus.

}, issn = {1098-1004}, doi = {10.1002/humu.24118}, author = {Montenegro-Garreaud, Ximena and Hansen, Adam W and Khayat, Michael M and Chander, Varuna and Grochowski, Christopher M and Jiang, Yunyun and Li, He and Mitani, Tadahiro and Kessler, Elena and Jayaseelan, Joy and Shen, Hua and Gezdirici, Alper and Pehlivan, Davut and Meng, Qingchang and Rosenfeld, Jill A and Jhangiani, Shalini N and Madan-Khetarpal, Suneeta and Scott, Daryl A and Abarca-Barriga, Hugo and Trubnykova, Milana and Gingras, Marie-Claude and Muzny, Donna M and Posey, Jennifer E and Liu, Pengfei and Lupski, James R and Gibbs, Richard A} } @article {720, title = {Xq22 deletions and correlation with distinct neurological disease traits in females: Further evidence for a contiguous gene syndrome.}, journal = {Hum Mutat}, volume = {41}, year = {2020}, month = {2020 01}, pages = {150-168}, abstract = {

Xq22 deletions that encompass PLP1 (Xq22-PLP1-DEL) are notable for variable expressivity of neurological disease traits in females ranging from a mild late-onset form of spastic paraplegia type 2 (MIM$\#$ 312920), sometimes associated with skewed X-inactivation, to an early-onset neurological disease trait (EONDT) of severe developmental delay, intellectual disability, and behavioral abnormalities. Size and gene content of Xq22-PLP1-DEL vary and were proposed as potential molecular etiologies underlying variable expressivity in carrier females where two smallest regions of overlap (SROs) were suggested to influence disease. We ascertained a cohort of eight unrelated patients harboring Xq22-PLP1-DEL and performed high-density array comparative genomic hybridization~and breakpoint-junction sequencing. Molecular characterization of Xq22-PLP1-DEL from 17 cases (eight herein and nine published) revealed an overrepresentation of breakpoints that reside within repeats (11/17, ~65\%) and the clustering of ~47\% of proximal breakpoints in a genomic instability hotspot with characteristic non-B DNA density. These findings implicate a potential role for genomic architecture in stimulating the formation of Xq22-PLP1-DEL. The correlation of Xq22-PLP1-DEL gene content with neurological disease trait in female cases enabled refinement of the associated SROs to a single genomic interval containing six genes. Our data support the hypothesis that genes contiguous to PLP1 contribute to EONDT.

}, keywords = {Child, Child, Preschool, Chromosome Breakpoints, Chromosome Deletion, Chromosome Mapping, Chromosomes, Human, X, Comparative Genomic Hybridization, Female, Genetic Association Studies, Genetic Predisposition to Disease, Humans, Male, Nervous System Diseases, Pedigree, Phenotype, Quantitative Trait, Heritable, Repetitive Sequences, Nucleic Acid, Sex Factors, Syndrome, X Chromosome Inactivation}, issn = {1098-1004}, doi = {10.1002/humu.23902}, author = {Hijazi, Hadia and Coelho, Fernanda S and Gonzaga-Jauregui, Claudia and Bernardini, Laura and Mar, Soe S and Manning, Melanie A and Hanson-Kahn, Andrea and Naidu, Sakkubai and Srivastava, Siddharth and Lee, Jennifer A and Jones, Julie R and Friez, Michael J and Alberico, Thomas and Torres, Barbara and Fang, Ping and Cheung, Sau Wai and Song, Xiaofei and Davis-Williams, Angelique and Jornlin, Carly and Wight, Patricia A and Patyal, Pankaj and Taube, Jennifer and Poretti, Andrea and Inoue, Ken and Zhang, Feng and Pehlivan, Davut and Carvalho, Claudia M B and Hobson, Grace M and Lupski, James R} } @article {692, title = {Biallelic CACNA2D2 variants in epileptic encephalopathy and cerebellar atrophy.}, journal = {Ann Clin Transl Neurol}, volume = {6}, year = {2019}, month = {2019 Aug}, pages = {1395-1406}, abstract = {

OBJECTIVE: To characterize the molecular and clinical phenotypic basis of developmental and epileptic encephalopathies caused by rare biallelic variants in CACNA2D2.

METHODS: Two affected individuals from a family with clinical features of early onset epileptic encephalopathy were recruited for exome sequencing at the Centers for Mendelian Genomics to identify their molecular diagnosis. GeneMatcher facilitated identification of a second family with a shared candidate disease gene identified through clinical gene panel-based testing.

RESULTS: Rare biallelic CACNA2D2 variants have been previously reported in three families with developmental and epileptic encephalopathy, and one family with congenital ataxia. We identified three individuals in two unrelated families with novel homozygous rare variants in CACNA2D2 with clinical features of developmental and epileptic encephalopathy and cerebellar atrophy. Family 1 includes two affected siblings with a likely damaging homozygous rare missense variant c.1778G>C; p.(Arg593Pro) in CACNA2D2. Family 2 includes a proband with a homozygous rare nonsense variant c.485_486del; p.(Tyr162Ter) in CACNA2D2. We compared clinical and molecular findings from all nine individuals reported to date and note that cerebellar atrophy is shared among all.

INTERPRETATION: Our study supports the candidacy of CACNA2D2 as a disease gene associated with a phenotypic spectrum of neurological disease that include features of developmental and epileptic encephalopathy, ataxia, and cerebellar atrophy. Age at presentation may affect apparent penetrance of neurogenetic trait manifestations and of a particular clinical neurological endophenotype, for example, seizures or ataxia.

}, issn = {2328-9503}, doi = {10.1002/acn3.50824}, author = {Punetha, Jaya and Karaca, Ender and Gezdirici, Alper and Lamont, Ryan E and Pehlivan, Davut and Marafi, Dana and Appendino, Juan P and Hunter, Jill V and Akdemir, Zeynep C and Fatih, Jawid M and Jhangiani, Shalini N and Gibbs, Richard A and Innes, A Micheil and Posey, Jennifer E and Lupski, James R} } @article {515, title = {Clinical exome sequencing reveals locus heterogeneity and phenotypic variability of cohesinopathies.}, journal = {Genet Med}, volume = {21}, year = {2019}, month = {2019 03}, pages = {663-675}, abstract = {

PURPOSE: Defects in the cohesin pathway are associated with cohesinopathies, notably Cornelia de Lange syndrome (CdLS). We aimed to delineate pathogenic variants~in known and candidate cohesinopathy genes from a clinical exome perspective.

METHODS: We retrospectively studied patients referred for clinical exome sequencing (CES, N = 10,698). Patients with causative variants in novel or recently described cohesinopathy genes were enrolled for phenotypic characterization.

RESULTS: Pathogenic or likely pathogenic single-nucleotide and insertion/deletion variants (SNVs/indels) were identified in established disease genes including NIPBL (N = 5), SMC1A (N = 14), SMC3 (N = 4), RAD21 (N = 2), and HDAC8 (N = 8). The phenotypes in this genetically defined cohort skew towards the mild end of CdLS spectrum as compared with phenotype-driven cohorts. Candidate or recently reported cohesinopathy genes were supported by de novo SNVs/indels in STAG1 (N = 3), STAG2 (N = 5), PDS5A (N = 1), and WAPL (N = 1), and one inherited SNV in PDS5A. We also identified copy-number deletions affecting STAG1 (two de novo, one of unknown inheritance) and STAG2 (one of unknown inheritance). Patients with STAG1 and STAG2 variants presented with overlapping features yet without characteristic facial features of CdLS.

CONCLUSION: CES effectively identified disease-causing alleles at the mild end of the cohensinopathy spectrum and enabled characterization of candidate disease genes.

}, keywords = {Adolescent, Alleles, Antigens, Nuclear, Biological Variation, Population, Carrier Proteins, Cell Cycle Proteins, Child, Child, Preschool, Chromosomal Proteins, Non-Histone, Cohort Studies, De Lange Syndrome, Exome, Female, Gene Frequency, Genetic Heterogeneity, Humans, INDEL Mutation, Male, Mutation, Nuclear Proteins, Phenotype, Polymorphism, Single Nucleotide, Proto-Oncogene Proteins, Retrospective Studies, Whole Exome Sequencing}, issn = {1530-0366}, doi = {10.1038/s41436-018-0085-6}, author = {Yuan, Bo and Neira, Juanita and Pehlivan, Davut and Santiago-Sim, Teresa and Song, Xiaofei and Rosenfeld, Jill and Posey, Jennifer E and Patel, Vipulkumar and Jin, Weihong and Adam, Margaret P and Baple, Emma L and Dean, John and Fong, Chin-To and Hickey, Scott E and Hudgins, Louanne and Leon, Eyby and Madan-Khetarpal, Suneeta and Rawlins, Lettie and Rustad, Cecilie F and Stray-Pedersen, Asbj{\o}rg and Tveten, Kristian and Wenger, Olivia and Diaz, Jullianne and Jenkins, Laura and Martin, Laura and McGuire, Marianne and Pietryga, Marguerite and Ramsdell, Linda and Slattery, Leah and Abid, Farida and Bertuch, Alison A and Grange, Dorothy and Immken, LaDonna and Schaaf, Christian P and Van Esch, Hilde and Bi, Weimin and Cheung, Sau Wai and Breman, Amy M and Smith, Janice L and Shaw, Chad and Crosby, Andrew H and Eng, Christine and Yang, Yaping and Lupski, James R and Xiao, Rui and Liu, Pengfei} } @article {680, title = {Exome Sequencing of a Primary Ovarian Insufficiency Cohort Reveals Common Molecular Etiologies for a Spectrum of Disease.}, journal = {J Clin Endocrinol Metab}, volume = {104}, year = {2019}, month = {2019 Aug 01}, pages = {3049-3067}, abstract = {

CONTEXT: Primary ovarian insufficiency (POI) encompasses a spectrum of premature menopause, including both primary and secondary amenorrhea. For 75\% to 90\% of individuals with hypergonadotropic hypogonadism presenting as POI, the molecular etiology is unknown. Common etiologies include chromosomal abnormalities, environmental factors, and congenital disorders affecting ovarian development and function, as well as syndromic and nonsyndromic single gene disorders suggesting POI represents a complex trait.

OBJECTIVE: To characterize the contribution of known disease genes to POI and identify molecular etiologies and biological underpinnings of POI.

DESIGN, SETTING, AND PARTICIPANTS: We applied exome sequencing (ES) and family-based genomics to 42 affected female individuals from 36 unrelated Turkish families, including 31 with reported parental consanguinity.

RESULTS: This analysis identified likely damaging, potentially contributing variants and molecular diagnoses in 16 families (44\%), including 11 families with likely damaging variants in known genes and five families with predicted deleterious variants in disease genes (IGSF10, MND1, MRPS22, and SOHLH1) not previously associated with POI. Of the 16 families, 2 (13\%) had evidence for potentially pathogenic variants at more than one locus. Absence of heterozygosity consistent with identity-by-descent mediated recessive disease burden contributes to molecular diagnosis in 15 of 16 (94\%) families. GeneMatcher allowed identification of additional families from diverse genetic backgrounds.

CONCLUSIONS: ES analysis of a POI cohort further characterized locus heterogeneity, reaffirmed the association of genes integral to meiotic recombination, demonstrated the likely contribution of genes involved in hypothalamic development, and documented multilocus pathogenic variation suggesting the potential for oligogenic inheritance contributing to the development of POI.

}, issn = {1945-7197}, doi = {10.1210/jc.2019-00248}, author = {Jolly, Angad and Bayram, Yavuz and Turan, Serap and Aycan, Zehra and Tos, Tulay and Abali, Zehra Yavas and Hacihamdioglu, Bulent and Coban Akdemir, Zeynep Hande and Hijazi, Hadia and Bas, Serpil and Atay, Zeynep and Guran, Tulay and Abali, Saygin and Bas, Firdevs and Darendeliler, Feyza and Colombo, Roberto and Barakat, Tahsin Stefan and Rinne, Tuula and White, Janson J and Yesil, G{\"o}zde and Gezdirici, Alper and Gulec, Elif Yilmaz and Karaca, Ender and Pehlivan, Davut and Jhangiani, Shalini N and Muzny, Donna M and Poyrazoglu, Sukran and Bereket, Abdullah and Gibbs, Richard A and Posey, Jennifer E and Lupski, James R} } @article {672, title = {The Genomics of Arthrogryposis, a Complex Trait: Candidate Genes and Further Evidence for Oligogenic Inheritance.}, journal = {Am J Hum Genet}, volume = {105}, year = {2019}, month = {2019 Jul 03}, pages = {132-150}, abstract = {

Arthrogryposis is a clinical finding that is present either as a feature of a neuromuscular condition or as part of a systemic disease in over 400 Mendelian conditions. The underlying molecular etiology remains largely unknown because of genetic and phenotypic heterogeneity. We applied exome sequencing (ES) in a cohort of 89 families with the clinical sign of arthrogryposis. Additional molecular techniques including array comparative genomic hybridization (aCGH) and Droplet Digital PCR (ddPCR) were performed on individuals who were found to have pathogenic copy number variants (CNVs) and mosaicism, respectively. A molecular diagnosis was established in 65.2\% (58/89) of families. Eleven out of 58 families (19.0\%) showed evidence for potential involvement of pathogenic variation at more than one locus, probably driven by absence of heterozygosity (AOH) burden due to identity-by-descent (IBD). RYR3, MYOM2, ERGIC1, SPTBN4, and ABCA7 represent genes, identified in two or more families, for which mutations are probably causative for arthrogryposis. We also provide evidence for the involvement of CNVs in the etiology of arthrogryposis and for the idea that both mono-allelic and bi-allelic variants in the same gene cause either similar or distinct syndromes. We were able to identify the molecular etiology in nine out of 20 families who underwent reanalysis. In summary, our data from family-based ES further delineate the molecular etiology of arthrogryposis, yielded several candidate disease-associated genes, and provide evidence for mutational burden in a biological pathway or network. Our study also highlights the importance of reanalysis of individuals with unsolved diagnoses in conjunction with sequencing extended family members.

}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2019.05.015}, author = {Pehlivan, Davut and Bayram, Yavuz and Gunes, Nilay and Coban Akdemir, Zeynep and Shukla, Anju and Bierhals, Tatjana and Tabakci, Burcu and Sahin, Yavuz and Gezdirici, Alper and Fatih, Jawid M and Gulec, Elif Yilmaz and Yesil, G{\"o}zde and Punetha, Jaya and Ocak, Zeynep and Grochowski, Christopher M and Karaca, Ender and Albayrak, Hatice Mutlu and Radhakrishnan, Periyasamy and Erdem, Haktan Bagis and Sahin, Ibrahim and Yildirim, Timur and Bayhan, Ilhan A and Bursali, Aysegul and Elmas, Muhsin and Yuksel, Zafer and Ozdemir, Ozturk and Silan, Fatma and Yildiz, Onur and Yesilbas, Osman and Isikay, Sedat and Balta, Burhan and Gu, Shen and Jhangiani, Shalini N and Doddapaneni, Harsha and Hu, Jianhong and Muzny, Donna M and Boerwinkle, Eric and Gibbs, Richard A and Tsiakas, Konstantinos and Hempel, Maja and Girisha, Katta Mohan and Gul, Davut and Posey, Jennifer E and Elcioglu, Nursel H and Tuysuz, Beyhan and Lupski, James R} } @article {716, title = {Homozygous Missense Variants in NTNG2, Encoding a Presynaptic Netrin-G2 Adhesion Protein, Lead to a Distinct Neurodevelopmental Disorder.}, journal = {Am J Hum Genet}, volume = {105}, year = {2019}, month = {2019 Nov 07}, pages = {1048-1056}, abstract = {

NTNG2 encodes netrin-G2, a membrane-anchored protein implicated in the molecular organization of neuronal circuitry and synaptic organization and diversification in vertebrates. In this study, through a combination of exome sequencing and autozygosity mapping, we have identified 16 individuals (from seven unrelated families) with ultra-rare homozygous missense variants in NTNG2; these individuals present with shared features of a neurodevelopmental disorder consisting of global developmental delay, severe to profound intellectual disability, muscle weakness and abnormal tone, autistic features, behavioral abnormalities, and variable dysmorphisms. The variants disrupt highly conserved residues across the protein. Functional experiments, including in silico analysis of the protein structure, in~vitro assessment of cell surface expression, and in~vitro knockdown, revealed potential mechanisms of pathogenicity of the variants, including loss of protein function and decreased neurite outgrowth. Our data indicate that appropriate expression of NTNG2 plays an important role in neurotypical development.

}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2019.09.025}, author = {Dias, Caroline M and Punetha, Jaya and Zheng, C{\'e}line and Mazaheri, Neda and Rad, Abolfazl and Efthymiou, Stephanie and Petersen, Andrea and Dehghani, Mohammadreza and Pehlivan, Davut and Partlow, Jennifer N and Posey, Jennifer E and Salpietro, Vincenzo and Gezdirici, Alper and Malamiri, Reza Azizi and Al Menabawy, Nihal M and Selim, Laila A and Vahidi Mehrjardi, Mohammad Yahya and Banu, Selina and Polla, Daniel L and Yang, Edward and Rezazadeh Varaghchi, Jamileh and Mitani, Tadahiro and van Beusekom, Ellen and Najafi, Maryam and Sedaghat, Alireza and Keller-Ramey, Jennifer and Durham, Leslie and Coban-Akdemir, Zeynep and Karaca, Ender and Orlova, Valeria and Schaeken, Lieke L M and Sherafat, Amir and Jhangiani, Shalini N and Stanley, Valentina and Shariati, Gholamreza and Galehdari, Hamid and Gleeson, Joseph G and Walsh, Christopher A and Lupski, James R and Seiradake, Elena and Houlden, Henry and van Bokhoven, Hans and Maroofian, Reza} } @article {595, title = {Insights into genetics, human biology and disease gleaned from family based genomic studies.}, journal = {Genet Med}, volume = {21}, year = {2019}, month = {2019 04}, pages = {798-812}, abstract = {

Identifying genes and variants contributing to rare disease phenotypes and Mendelian conditions informs biology and medicine, yet potential phenotypic consequences for variation of >75\% of the ~20,000 annotated genes in the human genome are lacking. Technical advances to assess rare variation genome-wide, particularly exome sequencing (ES), enabled establishment in the United States of the National Institutes of Health (NIH)-supported Centers for Mendelian Genomics (CMGs) and have facilitated collaborative studies resulting in~novel "disease gene" discoveries. Pedigree-based genomic studies and rare variant analyses in families with suspected Mendelian conditions have led to the elucidation of hundreds of novel disease genes and highlighted the impact of de novo mutational events, somatic variation underlying nononcologic traits, incompletely penetrant alleles, phenotypes with high locus heterogeneity, and multilocus pathogenic variation. Herein, we highlight CMG collaborative discoveries that have contributed to understanding both rare and common diseases and discuss opportunities for future discovery in single-locus Mendelian disorder genomics. Phenotypic annotation of all human genes; development of bioinformatic tools and analytic methods; exploration of non-Mendelian modes of inheritance including reduced penetrance, multilocus variation, and oligogenic inheritance; construction of allelic series at a locus; enhanced data sharing worldwide; and integration with clinical genomics are explored. Realizing the full contribution of rare disease research to functional annotation of the human genome, and further illuminating human biology and health, will lay the foundation for the Precision Medicine Initiative.

}, keywords = {Databases, Genetic, Genetic Diseases, Inborn, Genetic Heterogeneity, Genetic Predisposition to Disease, Genome, Human, Genomics, Humans, National Institutes of Health (U.S.), Pedigree, United States, Whole Exome Sequencing}, issn = {1530-0366}, doi = {10.1038/s41436-018-0408-7}, author = {Posey, Jennifer E and O{\textquoteright}Donnell-Luria, Anne H and Chong, Jessica X and Harel, Tamar and Jhangiani, Shalini N and Coban Akdemir, Zeynep H and Buyske, Steven and Pehlivan, Davut and Carvalho, Claudia M B and Baxter, Samantha and Sobreira, Nara and Liu, Pengfei and Wu, Nan and Rosenfeld, Jill A and Kumar, Sushant and Avramopoulos, Dimitri and White, Janson J and Doheny, Kimberly F and Witmer, P Dane and Boehm, Corinne and Sutton, V Reid and Muzny, Donna M and Boerwinkle, Eric and G{\"u}nel, Murat and Nickerson, Deborah A and Mane, Shrikant and MacArthur, Daniel G and Gibbs, Richard A and Hamosh, Ada and Lifton, Richard P and Matise, Tara C and Rehm, Heidi L and Gerstein, Mark and Bamshad, Michael J and Valle, David and Lupski, James R} } @article {682, title = {TBX6-associated congenital scoliosis (TACS) as a clinically distinguishable subtype of congenital scoliosis: further evidence supporting the compound inheritance and TBX6 gene dosage model.}, journal = {Genet Med}, volume = {21}, year = {2019}, month = {2019 07}, pages = {1548-1558}, abstract = {

PURPOSE: To characterize clinically measurable endophenotypes, implicating the TBX6 compound inheritance model.

METHODS: Patients with congenital scoliosis (CS) from China(N = 345, cohort 1), Japan (N = 142, cohort 2), and the United States (N = 10, cohort 3) were studied. Clinically measurable endophenotypes were compared according to the TBX6 genotypes. A mouse model for Tbx6 compound inheritance (N = 52) was investigated by micro computed tomography (micro-CT). A clinical diagnostic algorithm (TACScore) was developed to assist in clinical recognition of TBX6-associated CS (TACS).

RESULTS: In cohort 1, TACS patients (N = 33) were significantly younger at onset than the remaining CS patients (P = 0.02), presented with one or more hemivertebrae/butterfly vertebrae (P = 4.9 {\texttimes} 10), and exhibited vertebral malformations involving the lower part of the spine (T8-S5, P = 4.4 {\texttimes} 10); observations were confirmed in two replication cohorts. Simple rib anomalies were prevalent in TACS patients (P = 3.1 {\texttimes} 10), while intraspinal anomalies were uncommon (P = 7.0 {\texttimes} 10). A clinically usable TACScore was developed with an area under the curve (AUC) of 0.9 (P = 1.6 {\texttimes} 10). A Tbx6 mouse model supported that a~gene dosage effect underlies the TACS phenotype.

CONCLUSION: TACS is a clinically distinguishable entity with consistent clinically measurable endophenotypes. The type and distribution of vertebral column abnormalities in TBX6/Tbx6 compound inheritance implicate subtle perturbations in gene dosage as a cause of spine developmental birth defects responsible for about 10\% of CS.

}, issn = {1530-0366}, doi = {10.1038/s41436-018-0377-x}, author = {Liu, Jiaqi and Wu, Nan and Yang, Nan and Takeda, Kazuki and Chen, Weisheng and Li, Weiyu and Du, Renqian and Liu, Sen and Zhou, Yangzhong and Zhang, Ling and Liu, Zhenlei and Zuo, Yuzhi and Zhao, Sen and Blank, Robert and Pehlivan, Davut and Dong, Shuangshuang and Zhang, Jianguo and Shen, Jianxiong and Si, Nuo and Wang, Yipeng and Liu, Gang and Li, Shugang and Zhao, Yanxue and Zhao, Hong and Chen, Yixin and Zhao, Yu and Song, Xiaofei and Hu, Jianhua and Lin, Mao and Tian, Ye and Yuan, Bo and Yu, Keyi and Niu, Yuchen and Yu, Bin and Li, Xiaoxin and Chen, Jia and Yan, Zihui and Zhu, Qiankun and Meng, Xiaolu and Chen, Xiaoli and Su, Jianzhong and Zhao, Xiuli and Wang, Xiaoyue and Ming, Yue and Li, Xiao and Raggio, Cathleen L and Zhang, Baozhong and Weng, Xisheng and Zhang, Shuyang and Zhang, Xue and Watanabe, Kota and Matsumoto, Morio and Jin, Li and Shen, Yiping and Sobreira, Nara L and Posey, Jennifer E and Giampietro, Philip F and Valle, David and Liu, Pengfei and Wu, Zhihong and Ikegawa, Shiro and Lupski, James R and Zhang, Feng and Qiu, Guixing} } @article {562, title = {Bi-allelic CCDC47 Variants Cause a Disorder Characterized by Woolly Hair, Liver Dysfunction, Dysmorphic Features, and Global Developmental Delay.}, journal = {Am J Hum Genet}, volume = {103}, year = {2018}, month = {2018 11 01}, pages = {794-807}, abstract = {

Ca signaling is vital for various cellular processes including synaptic vesicle exocytosis, muscle contraction, regulation of secretion, gene transcription, and cellular proliferation. The endoplasmic reticulum (ER) is the largest intracellular Ca store, and dysregulation of ER Ca signaling and homeostasis contributes to the pathogenesis of various complex disorders and Mendelian disease traits. We describe four unrelated individuals with a complex multisystem disorder characterized by woolly hair, liver dysfunction, pruritus, dysmorphic features, hypotonia, and global developmental delay. Through whole-exome sequencing and family-based genomics, we identified bi-allelic variants in CCDC47 that encodes the Ca-binding ER transmembrane protein CCDC47. CCDC47, also known as calumin, has been shown to bind Ca with low affinity and high capacity. In mice, loss of Ccdc47 leads to embryonic lethality, suggesting that Ccdc47 is essential for early development. Characterization of cells from individuals with predicted likely damaging alleles showed decreased CCDC47 mRNA expression and protein levels. In~vitro cellular experiments showed decreased total ER Ca storage, impaired Ca signaling mediated by the IPR Ca release channel, and reduced ER Ca refilling via store-operated Ca entry. These results, together with the previously described role of CCDC47 in Ca signaling and development, suggest that bi-allelic loss-of-function variants in CCDC47 underlie the pathogenesis of this multisystem disorder.

}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2018.09.014}, author = {Morimoto, Marie and Waller-Evans, Helen and Ammous, Zineb and Song, Xiaofei and Strauss, Kevin A and Pehlivan, Davut and Gonzaga-Jauregui, Claudia and Puffenberger, Erik G and Holst, Charles R and Karaca, Ender and Brigatti, Karlla W and Maguire, Emily and Coban-Akdemir, Zeynep H and Amagata, Akiko and Lau, C Christopher and Chepa-Lotrea, Xenia and Macnamara, Ellen and Tos, Tulay and Isikay, Sedat and Nehrebecky, Michele and Overton, John D and Klein, Matthew and Markello, Thomas C and Posey, Jennifer E and Adams, David R and Lloyd-Evans, Emyr and Lupski, James R and Gahl, William A and Malicdan, May Christine V} } @article {612, title = {Phenotypic expansion illuminates multilocus pathogenic variation.}, journal = {Genet Med}, volume = {20}, year = {2018}, month = {2018 12}, pages = {1528-1537}, abstract = {

PURPOSE: Multilocus variation-pathogenic variants in two or more disease genes-can potentially explain the underlying genetic basis for apparent phenotypic expansion in cases for which the observed clinical features extend beyond those reported in association with a "known" disease gene.

METHODS: Analyses focused on 106 patients, 19 for whom apparent phenotypic expansion was previously attributed to variation at known disease genes. We performed a retrospective computational reanalysis of whole-exome sequencing data using stringent Variant Call File filtering criteria to determine whether molecular diagnoses involving additional disease loci might explain the observed expanded phenotypes.

RESULTS: Multilocus variation was identified in 31.6\% (6/19) of families with phenotypic expansion and 2.3\% (2/87) without phenotypic expansion. Intrafamilial clinical variability within two families was explained by multilocus variation identified in the more severely affected sibling.

CONCLUSION: Our findings underscore the role of multiple rare variants at different loci in the etiology of genetically and clinically heterogeneous cohorts. Intrafamilial phenotypic and genotypic variability allowed a dissection of genotype-phenotype relationships in two families. Our data emphasize the critical role of the clinician in diagnostic genomic analyses and demonstrate that apparent phenotypic expansion may represent blended phenotypes resulting from pathogenic variation at more than one locus.

}, issn = {1530-0366}, doi = {10.1038/gim.2018.33}, author = {Karaca, Ender and Posey, Jennifer E and Coban Akdemir, Zeynep and Pehlivan, Davut and Harel, Tamar and Jhangiani, Shalini N and Bayram, Yavuz and Song, Xiaofei and Bahrambeigi, Vahid and Yuregir, Ozge Ozalp and Bozdogan, Sevcan and Yesil, G{\"o}zde and Isikay, Sedat and Muzny, Donna and Gibbs, Richard A and Lupski, James R} } @article {506, title = {Phenotypic expansion in - a common cause of intellectual disability in females.}, journal = {Ann Clin Transl Neurol}, volume = {5}, year = {2018}, month = {2018 Oct}, pages = {1277-1285}, abstract = {

De variants in account for 1-3\% of unexplained intellectual disability (ID) cases and are amongst the most common causes of ID especially in females. Forty-seven patients (44 females, 3 males) have been described. We identified 31 additional individuals carrying 29 unique variants, including 30 postnatal individuals with complex clinical presentations of developmental delay or ID, and one fetus with abnormal ultrasound findings. Rare or novel phenotypes observed include respiratory problems, congenital heart disease, skeletal muscle mitochondrial DNA depletion, and late-onset neurologic decline. Our findings expand the spectrum of DNA variants and phenotypes associated with disorders.

}, issn = {2328-9503}, doi = {10.1002/acn3.622}, author = {Wang, Xia and Posey, Jennifer E and Rosenfeld, Jill A and Bacino, Carlos A and Scaglia, Fernando and Immken, LaDonna and Harris, Jill M and Hickey, Scott E and Mosher, Theresa M and Slavotinek, Anne and Zhang, Jing and Beuten, Joke and Leduc, Magalie S and He, Weimin and Vetrini, Francesco and Walkiewicz, Magdalena A and Bi, Weimin and Xiao, Rui and Liu, Pengfei and Shao, Yunru and Gezdirici, Alper and Gulec, Elif Y and Jiang, Yunyun and Darilek, Sandra A and Hansen, Adam W and Khayat, Michael M and Pehlivan, Davut and Piard, Juliette and Muzny, Donna M and Hanchard, Neil and Belmont, John W and Van Maldergem, Lionel and Gibbs, Richard A and Eldomery, Mohammad K and Akdemir, Zeynep C and Adesina, Adekunle M and Chen, Shan and Lee, Yi-Chien and Lee, Brendan and Lupski, James R and Eng, Christine M and Xia, Fan and Yang, Yaping and Graham, Brett H and Moretti, Paolo} } @article {390, title = {REST Final-Exon-Truncating Mutations Cause Hereditary Gingival Fibromatosis.}, journal = {Am J Hum Genet}, volume = {101}, year = {2017}, month = {2017 Jul 06}, pages = {149-156}, abstract = {

Hereditary gingival fibromatosis (HGF) is the most common genetic form of gingival fibromatosis that develops as a slowly progressive, benign, localized or generalized enlargement of keratinized gingiva. HGF is a genetically heterogeneous disorder and can be transmitted either as an autosomal-dominant or autosomal-recessive trait or appear sporadically. To date, four loci (2p22.1, 2p23.3-p22.3, 5q13-q22, and 11p15) have been mapped to autosomes and one gene (SOS1) has been associated with the HGF trait observed to segregate in a dominant inheritance pattern. Here we report 11 individuals with HGF from three unrelated families. Whole-exome sequencing (WES) revealed three different truncating mutations including two frameshifts and one nonsense variant in RE1-silencing transcription factor (REST) in the probands from all families and further genetic and genomic analyses confirmed the WES-identified findings. REST is a transcriptional repressor that is expressed throughout the body; it has different roles in different cellular contexts, such as oncogenic and tumor-suppressor functions and hematopoietic and cardiac differentiation. Here we show the consequences of germline final-exon-truncating mutations in REST for organismal development and the association with the HGF phenotype.

}, keywords = {Adolescent, Base Sequence, Chromosome Segregation, Exons, Family, Female, Fibromatosis, Gingival, Genetic Predisposition to Disease, Humans, Male, Middle Aged, Mutation, Pedigree, Repressor Proteins}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2017.06.006}, author = {Bayram, Yavuz and White, Janson J and Elcioglu, Nursel and Cho, Megan T and Zadeh, Neda and Gedikbasi, Asuman and Palanduz, Sukru and Ozturk, Sukru and Cefle, Kivanc and Kasapcopur, Ozgur and Coban Akdemir, Zeynep and Pehlivan, Davut and Begtrup, Amber and Carvalho, Claudia M B and Paine, Ingrid Sophie and Mentes, Ali and Bektas-Kayhan, Kivanc and Karaca, Ender and Jhangiani, Shalini N and Muzny, Donna M and Gibbs, Richard A and Lupski, James R} } @article {30, title = {Copy-Number Variation Contributes to the Mutational Load of Bardet-Biedl Syndrome.}, journal = {Am J Hum Genet}, volume = {99}, year = {2016}, month = {2016 Aug 04}, pages = {318-36}, abstract = {

Bardet-Biedl syndrome (BBS) is a defining ciliopathy, notable for extensive allelic and genetic heterogeneity, almost all of which has been identified through sequencing. Recent data have suggested that copy-number variants (CNVs) also contribute to BBS. We used a custom oligonucleotide array comparative genomic hybridization (aCGH) covering 20 genes that encode intraflagellar transport (IFT) components and 74 ciliopathy loci to screen 92 unrelated individuals with BBS, irrespective of their known mutational burden. We identified 17 individuals with exon-disruptive CNVs (18.5\%), including 13 different deletions in eight BBS genes (BBS1, BBS2, ARL6/BBS3, BBS4, BBS5, BBS7, BBS9, and NPHP1) and a deletion and a duplication in other ciliopathy-associated genes (ALMS1 and NPHP4, respectively). By contrast, we found a single heterozygous exon-disruptive event in a BBS-associated gene (BBS9) in 229 control subjects. Superimposing these data with resequencing revealed CNVs to (1) be sufficient to cause disease, (2) Mendelize heterozygous deleterious alleles, and (3) contribute oligogenic alleles by combining point mutations and exonic CNVs in multiple genes. Finally, we report a deletion and a splice site mutation in IFT74, inherited under a recessive paradigm, defining a candidate BBS locus. Our data suggest that CNVs contribute pathogenic alleles to a substantial fraction of BBS-affected individuals and highlight how either deletions or point mutations in discrete splice isoforms can induce hypomorphic mutations in genes otherwise intolerant to deleterious variation. Our data also suggest that CNV analyses and resequencing studies unbiased for previous mutational burden is necessary to delineate the complexity of disease architecture.

}, keywords = {Adolescent, Adult, Alleles, Animals, Bardet-Biedl Syndrome, Child, Child, Preschool, Chromosome Breakpoints, Cytoskeletal Proteins, DNA Copy Number Variations, Exons, Female, Gastrulation, Genes, Recessive, Humans, Infant, Male, Mutation, Pedigree, Young Adult, Zebrafish, Zebrafish Proteins}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2015.04.023}, author = {Lindstrand, Anna and Frangakis, Stephan and Carvalho, Claudia M B and Richardson, Ellen B and McFadden, Kelsey A and Willer, Jason R and Pehlivan, Davut and Liu, Pengfei and Pediaditakis, Igor L and Sabo, Aniko and Lewis, Richard Alan and Banin, Eyal and Lupski, James R and Davis, Erica E and Katsanis, Nicholas} } @article {95, title = {Molecular etiology of arthrogryposis in multiple families of mostly Turkish origin.}, journal = {J Clin Invest}, volume = {126}, year = {2016}, month = {2016 Feb}, pages = {762-78}, abstract = {

BACKGROUND: Arthrogryposis, defined as congenital joint contractures in 2 or more body areas, is a clinical sign rather than a specific disease diagnosis. To date, more than 400 different disorders have been described that present with arthrogryposis, and variants of more than 220 genes have been associated with these disorders; however, the underlying molecular etiology remains unknown in the considerable majority of these cases.

METHODS: We performed whole exome sequencing (WES) of 52 patients with clinical presentation of arthrogryposis from 48 different families.

RESULTS: Affected individuals from 17 families (35.4\%) had variants in known arthrogryposis-associated genes, including homozygous variants of cholinergic γ nicotinic receptor (CHRNG, 6 subjects) and endothelin converting enzyme-like 1 (ECEL1, 4 subjects). Deleterious variants in candidate arthrogryposis-causing genes (fibrillin 3 [FBN3], myosin IXA [MYO9A], and pleckstrin and Sec7 domain containing 3 [PSD3]) were identified in 3 families (6.2\%). Moreover, in 8 families with a homozygous mutation in an arthrogryposis-associated gene, we identified a second locus with either a homozygous or compound heterozygous variant in a candidate gene (myosin binding protein C, fast type [MYBPC2] and vacuolar protein sorting 8 [VPS8], 2 families, 4.2\%) or in another disease-associated genes (6 families, 12.5\%), indicating a potential mutational burden contributing to disease expression.

CONCLUSION: In 58.3\% of families, the arthrogryposis manifestation could be explained by a molecular diagnosis; however, the molecular etiology in subjects from 20 families remained unsolved by WES. Only 5 of these 20 unrelated subjects had a clinical presentation consistent with amyoplasia; a phenotype not thought to be of genetic origin. Our results indicate that increased use of genome-wide technologies will provide opportunities to better understand genetic models for diseases and molecular mechanisms of genetically heterogeneous disorders, such as arthrogryposis.

FUNDING: This work was supported in part by US National Human Genome Research Institute (NHGRI)/National Heart, Lung, and Blood Institute (NHLBI) grant U54HG006542 to the Baylor-Hopkins Center for Mendelian Genomics, and US National Institute of Neurological Disorders and Stroke (NINDS) grant R01NS058529 to J.R. Lupski.

}, keywords = {Arthrogryposis, Exome, Family, Female, Genome-Wide Association Study, Humans, Male, Turkey}, issn = {1558-8238}, doi = {10.1172/JCI84457}, author = {Bayram, Yavuz and Karaca, Ender and Coban Akdemir, Zeynep and Yilmaz, Elif Ozdamar and Tayfun, Gulsen Akay and Aydin, Hatip and Torun, Deniz and Bozdogan, Sevcan Tug and Gezdirici, Alper and Isikay, Sedat and Atik, Mehmed M and Gambin, Tomasz and Harel, Tamar and El-Hattab, Ayman W and Charng, Wu-Lin and Pehlivan, Davut and Jhangiani, Shalini N and Muzny, Donna M and Karaman, Ali and Celik, Tamer and Yuregir, Ozge Ozalp and Yildirim, Timur and Bayhan, Ilhan A and Boerwinkle, Eric and Gibbs, Richard A and Elcioglu, Nursel and Tuysuz, Beyhan and Lupski, James R} } @article {75, title = {Monoallelic and Biallelic Variants in EMC1 Identified in Individuals with Global Developmental Delay, Hypotonia, Scoliosis, and Cerebellar Atrophy.}, journal = {Am J Hum Genet}, volume = {98}, year = {2016}, month = {2016 Mar 03}, pages = {562-570}, abstract = {

The paradigm of a single gene associated with one specific phenotype and mode of inheritance has been repeatedly challenged. Genotype-phenotype correlations can often be traced to different mutation types, localization of the variants in distinct protein domains, or the trigger of or escape from nonsense-mediated decay. Using whole-exome sequencing, we identified homozygous variants in EMC1 that segregated with a phenotype of developmental delay, hypotonia, scoliosis, and cerebellar atrophy in three families. In addition, a de novo heterozygous EMC1 variant was seen in an individual with a similar clinical and MRI imaging phenotype. EMC1 encodes a member of the endoplasmic reticulum (ER)-membrane protein complex (EMC), an evolutionarily conserved complex that has been proposed to have multiple roles in ER-associated degradation, ER-mitochondria tethering, and proper assembly of multi-pass transmembrane proteins. Perturbations of protein folding and organelle crosstalk have been implicated in neurodegenerative processes including cerebellar atrophy. We propose EMC1 as a gene in which either biallelic or monoallelic variants might lead to a syndrome including intellectual disability and preferential degeneration of the cerebellum.

}, keywords = {Adolescent, Alleles, Amino Acid Sequence, Atrophy, Cerebellum, Child, Child, Preschool, Developmental Disabilities, Endoplasmic Reticulum-Associated Degradation, Female, Genetic Association Studies, Genetic Variation, Heterozygote, Humans, Magnetic Resonance Imaging, Male, Molecular Sequence Data, Muscle Hypotonia, Mutation, Pedigree, Protein Folding, Proteins, Scoliosis}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2016.01.011}, author = {Harel, Tamar and Yesil, G{\"o}zde and Bayram, Yavuz and Coban-Akdemir, Zeynep and Charng, Wu-Lin and Karaca, Ender and Al Asmari, Ali and Eldomery, Mohammad K and Hunter, Jill V and Jhangiani, Shalini N and Rosenfeld, Jill A and Pehlivan, Davut and El-Hattab, Ayman W and Saleh, Mohammed A and LeDuc, Charles A and Muzny, Donna and Boerwinkle, Eric and Gibbs, Richard A and Chung, Wendy K and Yang, Yaping and Belmont, John W and Lupski, James R} } @article {140, title = {Phenotypic Expansion of Congenital Disorder of Glycosylation Due to SRD5A3 Null Mutation.}, journal = {JIMD Rep}, volume = {26}, year = {2016}, month = {2016}, pages = {7-12}, abstract = {

We present a boy, admitted at 4 months, with facial dysmorphism, hypertrichosis, loose skin, bilateral inguinal hernia, severe hypotonia, psychomotor disability, seizures with hypsarrhythmia (West syndrome), hepatosplenomegaly, increased serum transaminases, iris coloboma, glaucoma, corneal clouding and bilateral dilated lateral ventricles, and extra-axial post-cerebellar space. Serum transferrin isoelectrofocusing (IEF) showed a type 1 pattern. Whole-exome genotyping showed a previously reported homozygous nonsense mutation c.320G>A; p.Trp107X in SRD5A3. Epilepsy and glaucoma have been reported only once in the 19 described SRD5A3-congenital glycosylation defect patients, and corneal clouding not at all.

}, issn = {2192-8304}, doi = {10.1007/8904_2015_478}, author = {Tuysuz, Beyhan and Pehlivan, Davut and {\"O}zk{\"o}k, Ahmet and Jhangiani, Shalini and Yalcinkaya, Cengiz and Zeybek, {\c C}i{\u g}dem Aktu{\u g}lu and Muzny, Donna Marie and Lupski, James R and Gibbs, Richard and Jaeken, Jaak} } @article {345, title = {The role of combined SNV and CNV burden in patients with distal symmetric polyneuropathy.}, journal = {Genet Med}, volume = {18}, year = {2016}, month = {2016 05}, pages = {443-51}, abstract = {

PURPOSE: Charcot-Marie-Tooth (CMT) disease is a heterogeneous group of genetic disorders of the peripheral nervous system. Copy-number variants (CNVs) contribute significantly to CMT, as duplication of PMP22 underlies the majority of CMT1 cases. We hypothesized that CNVs and/or single-nucleotide variants (SNVs) might exist in patients with CMT with an unknown molecular genetic etiology.

METHODS: Two hundred patients with CMT, negative for both SNV mutations in several CMT genes and for CNVs involving PMP22, were screened for CNVs by high-resolution oligonucleotide array comparative genomic hybridization. Whole-exome sequencing was conducted on individuals with rare, potentially pathogenic CNVs.

RESULTS: Putatively causative CNVs were identified in five subjects (~2.5\%); four of the five map to known neuropathy genes. Breakpoint sequencing revealed Alu-Alu-mediated junctions as a predominant contributor. Exome sequencing identified MFN2 SNVs in two of the individuals.

CONCLUSION: Neuropathy-associated CNV outside of the PMP22 locus is rare in CMT. Nevertheless, there is potential clinical utility in testing for CNVs and exome sequencing in CMT cases negative for the CMT1A duplication. These findings suggest that complex phenotypes including neuropathy can potentially be caused by a combination of SNVs and CNVs affecting more than one disease-associated locus and contributing to a mutational burden.Genet Med 18 5, 443-451.

}, keywords = {Adult, Age of Onset, Charcot-Marie-Tooth Disease, Child, Preschool, Comparative Genomic Hybridization, DNA Copy Number Variations, Exome, Female, Genetic Predisposition to Disease, GTP Phosphohydrolases, High-Throughput Nucleotide Sequencing, Humans, Male, Mitochondrial Proteins, Motor Neurons, Myelin P0 Protein, Myelin Proteins, Neural Conduction, Polymorphism, Single Nucleotide, Polyneuropathies}, issn = {1530-0366}, doi = {10.1038/gim.2015.124}, author = {Pehlivan, Davut and Beck, Christine R and Okamoto, Yuji and Harel, Tamar and Akdemir, Zeynep H C and Jhangiani, Shalini N and Withers, Marjorie A and Goksungur, Meryem Tuba and Carvalho, Claudia M B and Czesnik, Dirk and Gonzaga-Jauregui, Claudia and Wiszniewski, Wojciech and Muzny, Donna M and Gibbs, Richard A and Rautenstrauss, Bernd and Sereda, Michael W and Lupski, James R} } @article {135, title = {Exome Sequence Analysis Suggests that Genetic Burden Contributes to Phenotypic Variability and Complex Neuropathy.}, journal = {Cell Rep}, volume = {12}, year = {2015}, month = {2015 Aug 18}, pages = {1169-83}, abstract = {

Charcot-Marie-Tooth (CMT) disease is a clinically and genetically heterogeneous distal symmetric polyneuropathy. Whole-exome sequencing (WES) of 40 individuals from 37 unrelated families with CMT-like peripheral neuropathy refractory to molecular diagnosis identified apparent causal mutations in \~{} 45\% (17/37) of families. Three candidate disease genes are proposed, supported by a combination of genetic and in vivo studies. Aggregate analysis of mutation data revealed a significantly increased number of rare variants across 58 neuropathy-associated genes in subjects versus controls, confirmed in a second ethnically discrete neuropathy cohort, suggesting that mutation burden potentially contributes to phenotypic variability. Neuropathy genes shown to have highly penetrant Mendelizing variants (HPMVs) and implicated by burden in families were shown to interact genetically in a zebrafish assay exacerbating the phenotype established by the suppression of single genes. Our findings suggest that the combinatorial effect of rare variants contributes to disease burden and variable expressivity.

}, keywords = {Animals, Charcot-Marie-Tooth Disease, Exome, Female, Genetic Load, Genetic Variation, HSP40 Heat-Shock Proteins, Humans, Male, Mutation, Myelin P2 Protein, Pedigree, Penetrance, Peripheral Nervous System Diseases, Phenotype, Serine C-Palmitoyltransferase, Suppression, Genetic, Zebrafish}, issn = {2211-1247}, doi = {10.1016/j.celrep.2015.07.023}, author = {Gonzaga-Jauregui, Claudia and Harel, Tamar and Gambin, Tomasz and Kousi, Maria and Griffin, Laurie B and Francescatto, Ludmila and Ozes, Burcak and Karaca, Ender and Jhangiani, Shalini N and Bainbridge, Matthew N and Lawson, Kim S and Pehlivan, Davut and Okamoto, Yuji and Withers, Marjorie and Mancias, Pedro and Slavotinek, Anne and Reitnauer, Pamela J and Goksungur, Meryem T and Shy, Michael and Crawford, Thomas O and Koenig, Michel and Willer, Jason and Flores, Brittany N and Pediaditrakis, Igor and Us, Onder and Wiszniewski, Wojciech and Parman, Yesim and Antonellis, Anthony and Muzny, Donna M and Katsanis, Nicholas and Battaloglu, Esra and Boerwinkle, Eric and Gibbs, Richard A and Lupski, James R} } @article {181, title = {Exome sequencing identifies a homozygous C5orf42 variant in a Turkish kindred with oral-facial-digital syndrome type VI.}, journal = {Am J Med Genet A}, volume = {167A}, year = {2015}, month = {2015 Sep}, pages = {2132-7}, abstract = {

Oral-facial-digital syndrome type VI (OFDVI) is a rare ciliopathy in the spectrum of Joubert syndrome (JS) and distinguished from other oral-facial-digital syndromes by metacarpal abnormalities with central polydactyly and by a molar tooth sign on cranial MRI. Additional characteristic features include short stature, micrognathia, posteriorly rotated low-set ears, hypertelorism, epicanthal folds, broad nasal tip, tongue hamartoma, upper lip notch, intraoral frenula, cleft lip/palate, and renal anomalies. Recently, novel mutations in C5orf42 were identified in 9 out of 11 OFDVI families. In a subsequent study C5orf42 was found to be mutated in only 2 out of 17 OFDVI probands while 28 patients with a pure JS phenotype also had pathogenic mutations of C5orf42. We report on two affected cousins diagnosed with OFDVI who were born from first degree cousin marriages. Whole exome sequencing (WES) identified a homozygous predicted damaging missense mutation (c.4034A > G; p.Gln1345Arg) in the C5orf42 gene. Our data contribute to the evidence that C5orf42 is one of the causative genes for OFDVI.

}, keywords = {Abnormalities, Multiple, Cerebellar Diseases, Cerebellum, Child, Cleft Palate, Exome, Eye Abnormalities, Female, Genetic Predisposition to Disease, Hamartoma, Homozygote, Humans, Kidney Diseases, Cystic, Magnetic Resonance Imaging, Male, Membrane Proteins, Middle Aged, Mutation, Orofaciodigital Syndromes, Phenotype, Retina, Turkey}, issn = {1552-4833}, doi = {10.1002/ajmg.a.37092}, author = {Bayram, Yavuz and Aydin, Hatip and Gambin, Tomasz and Akdemir, Zeynep Coban and Atik, Mehmed M and Karaca, Ender and Karaman, Ali and Pehlivan, Davut and Jhangiani, Shalini N and Gibbs, Richard A and Lupski, James R} } @article {174, title = {Exome sequencing reveals homozygous TRIM2 mutation in a patient with early onset CMT and bilateral vocal cord paralysis.}, journal = {Hum Genet}, volume = {134}, year = {2015}, month = {2015 Jun}, pages = {671-3}, abstract = {

Charcot-Marie-Tooth disease is a heterogeneous group of inherited distal symmetric polyneuropathies associated with mutations in genes encoding components essential for normal functioning of the Schwann cell and axon. TRIM2, encoding a ligase that ubiquitinates the neurofilament light chain, was recently associated with early-onset neuropathy in a single patient. We report a TRIM2 homozygous missense mutation (c.2000A>C; p.D667A) in a patient with peripheral neuropathy and bilateral vocal cord paralysis, allowing for further delineation of the associated phenotypic spectrum.

}, keywords = {Adult, Charcot-Marie-Tooth Disease, Exome, Female, High-Throughput Nucleotide Sequencing, Homozygote, Humans, Infant, Newborn, Male, Mutation, Missense, Nuclear Proteins, Vocal Cord Paralysis}, issn = {1432-1203}, doi = {10.1007/s00439-015-1548-3}, author = {Pehlivan, Davut and Coban Akdemir, Zeynep and Karaca, Ender and Bayram, Yavuz and Jhangiani, Shalini and Yildiz, Edibe Pembegul and Muzny, Donna and Uluc, Kayihan and Gibbs, Richard A and Elcioglu, Nursel and Lupski, James R and Harel, Tamar} } @article {121, title = {Genes that Affect Brain Structure and Function Identified by Rare Variant Analyses of Mendelian Neurologic Disease.}, journal = {Neuron}, volume = {88}, year = {2015}, month = {2015 Nov 04}, pages = {499-513}, abstract = {

Development of the human nervous system involves complex interactions among fundamental cellular processes and requires a multitude of genes, many of which remain to be associated with human disease. We applied whole exome sequencing to 128 mostly consanguineous families with neurogenetic disorders that often included brain malformations. Rare variant analyses for both single nucleotide variant (SNV) and copy number variant (CNV) alleles allowed for identification of 45 novel variants in 43 known disease genes, 41 candidate genes, and CNVs in 10 families, with an overall potential molecular cause identified in >85\% of families studied. Among the candidate genes identified, we found PRUNE, VARS, and DHX37 in multiple families and homozygous loss-of-function variants in AGBL2, SLC18A2, SMARCA1, UBQLN1, and CPLX1. Neuroimaging and in silico analysis of functional and expression proximity between candidate and known disease genes allowed for further understanding of genetic networks underlying specific types of brain malformations.

}, keywords = {Brain, Cohort Studies, Databases, Genetic, Female, Gene Regulatory Networks, Genetic Association Studies, Genetic Variation, Humans, Male, Mendelian Randomization Analysis, Nervous System Diseases, Pedigree}, issn = {1097-4199}, doi = {10.1016/j.neuron.2015.09.048}, author = {Karaca, Ender and Harel, Tamar and Pehlivan, Davut and Jhangiani, Shalini N and Gambin, Tomasz and Coban Akdemir, Zeynep and Gonzaga-Jauregui, Claudia and Erdin, Serkan and Bayram, Yavuz and Campbell, Ian M and Hunter, Jill V and Atik, Mehmed M and Van Esch, Hilde and Yuan, Bo and Wiszniewski, Wojciech and Isikay, Sedat and Yesil, G{\"o}zde and Yuregir, Ozge O and Tug Bozdogan, Sevcan and Aslan, Huseyin and Aydin, Hatip and Tos, Tulay and Aksoy, Ayse and De Vivo, Darryl C and Jain, Preti and Geckinli, B Bilge and Sezer, Ozlem and Gul, Davut and Durmaz, Burak and Cogulu, Ozgur and Ozkinay, Ferda and Topcu, Vehap and Candan, Sukru and Cebi, Alper Han and Ikbal, Mevlit and Yilmaz Gulec, Elif and Gezdirici, Alper and Koparir, Erkan and Ekici, Fatma and Coskun, Salih and Cicek, Salih and Karaer, Kadri and Koparir, Asuman and Duz, Mehmet Bugrahan and Kirat, Emre and Fenercioglu, Elif and Ulucan, Hakan and Seven, Mehmet and Guran, Tulay and Elcioglu, Nursel and Yildirim, Mahmut Selman and Aktas, Dilek and Alika{\c s}ifo{\u g}lu, Mehmet and Ture, Mehmet and Yakut, Tahsin and Overton, John D and Yuksel, Adnan and Ozen, Mustafa and Muzny, Donna M and Adams, David R and Boerwinkle, Eric and Chung, Wendy K and Gibbs, Richard A and Lupski, James R} } @article {198, title = {Global transcriptional disturbances underlie Cornelia de Lange syndrome and related phenotypes.}, journal = {J Clin Invest}, volume = {125}, year = {2015}, month = {2015 Feb}, pages = {636-51}, abstract = {

Cornelia de Lange syndrome (CdLS) is a genetically heterogeneous disorder that presents with extensive phenotypic variability, including facial dysmorphism, developmental delay/intellectual disability (DD/ID), abnormal extremities, and hirsutism. About 65\% of patients harbor mutations in genes that encode subunits or regulators of the cohesin complex, including NIPBL, SMC1A, SMC3, RAD21, and HDAC8. Wiedemann-Steiner syndrome (WDSTS), which shares CdLS phenotypic features, is caused by mutations in lysine-specific methyltransferase 2A (KMT2A). Here, we performed whole-exome sequencing (WES) of 2 male siblings clinically diagnosed with WDSTS; this revealed a hemizygous, missense mutation in SMC1A that was predicted to be deleterious. Extensive clinical evaluation and WES of 32 Turkish patients clinically diagnosed with CdLS revealed the presence of a de novo heterozygous nonsense KMT2A mutation in 1 patient without characteristic WDSTS features. We also identified de novo heterozygous mutations in SMC3 or SMC1A that affected RNA splicing in 2 independent patients with combined CdLS and WDSTS features. Furthermore, in families from 2 separate world populations segregating an autosomal-recessive disorder with CdLS-like features, we identified homozygous mutations in TAF6, which encodes a core transcriptional regulatory pathway component. Together, our data, along with recent transcriptome studies, suggest that CdLS and related phenotypes may be "transcriptomopathies" rather than cohesinopathies.

}, keywords = {Adolescent, Adult, Cell Cycle Proteins, Child, Child, Preschool, Chondroitin Sulfate Proteoglycans, Chromosomal Proteins, Non-Histone, Codon, Nonsense, De Lange Syndrome, Exome, Exonucleases, Gene Expression Profiling, Gene Expression Regulation, Genome-Wide Association Study, Heterozygote, Histone Deacetylases, Histone-Lysine N-Methyltransferase, Humans, Infant, Male, Myeloid-Lymphoid Leukemia Protein, Phenotype, Proteins, Repressor Proteins, Transcriptome}, issn = {1558-8238}, doi = {10.1172/JCI77435}, author = {Yuan, Bo and Pehlivan, Davut and Karaca, Ender and Patel, Nisha and Charng, Wu-Lin and Gambin, Tomasz and Gonzaga-Jauregui, Claudia and Sutton, V Reid and Yesil, G{\"o}zde and Bozdogan, Sevcan Tug and Tos, Tulay and Koparir, Asuman and Koparir, Erkan and Beck, Christine R and Gu, Shen and Aslan, Huseyin and Yuregir, Ozge Ozalp and Al Rubeaan, Khalid and Alnaqeb, Dhekra and Alshammari, Muneera J and Bayram, Yavuz and Atik, Mehmed M and Aydin, Hatip and Geckinli, B Bilge and Seven, Mehmet and Ulucan, Hakan and Fenercioglu, Elif and Ozen, Mustafa and Jhangiani, Shalini and Muzny, Donna M and Boerwinkle, Eric and Tuysuz, Beyhan and Alkuraya, Fowzan S and Gibbs, Richard A and Lupski, James R} } @article {186, title = {Homozygous loss-of-function mutations in SOHLH1 in patients with nonsyndromic hypergonadotropic hypogonadism.}, journal = {J Clin Endocrinol Metab}, volume = {100}, year = {2015}, month = {2015 May}, pages = {E808-14}, abstract = {

CONTEXT: Hypergonadotropic hypogonadism presents in females with delayed or arrested puberty, primary or secondary amenorrhea due to gonadal dysfunction, and is further characterized by elevated gonadotropins and low sex steroids. Chromosomal aberrations and various specific gene defects can lead to hypergonadotropic hypogonadism. Responsible genes include those with roles in gonadal development or maintenance, sex steroid synthesis, or end-organ resistance to gonadotropins. Identification of novel causative genes in this disorder will contribute to our understanding of the regulation of human reproductive function.

OBJECTIVES: The aim of this study was to identify and report the gene responsible for autosomal-recessive hypergonadotropic hypogonadism in two unrelated families.

DESIGN AND PARTICIPANTS: Clinical evaluation and whole-exome sequencing were performed in two pairs of sisters with nonsyndromic hypergonadotropic hypogonadism from two unrelated families.

RESULTS: Exome sequencing analysis revealed two different truncating mutations in the same gene: SOHLH1 c.705delT (p.Pro235fs*4) and SOHLH1 c.27C>G (p.Tyr9stop). Both mutations were unique to the families and segregation was consistent with Mendelian expectations for an autosomal-recessive mode of inheritance.

CONCLUSIONS: Sohlh1 was known from previous mouse studies to be a transcriptional regulator that functions in the maintenance and survival of primordial ovarian follicles, but loss-of-function mutations in human females have not been reported. Our results provide evidence that homozygous-truncating mutations in SOHLH1 cause female nonsyndromic hypergonadotropic hypogonadism.

}, keywords = {Adolescent, Basic Helix-Loop-Helix Transcription Factors, Child, Exome, Female, Homozygote, Humans, Hypogonadism, Mutation}, issn = {1945-7197}, doi = {10.1210/jc.2015-1150}, author = {Bayram, Yavuz and Gulsuner, Suleyman and Guran, Tulay and Abaci, Ayhan and Yesil, G{\"o}zde and Gulsuner, Hilal Unal and Atay, Zeynep and Pierce, Sarah B and Gambin, Tomasz and Lee, Ming and Turan, Serap and Bober, Ece and Atik, Mehmed M and Walsh, Tom and Karaca, Ender and Pehlivan, Davut and Jhangiani, Shalini N and Muzny, Donna and Bereket, Abdullah and Buyukgebiz, Atilla and Boerwinkle, Eric and Gibbs, Richard A and King, Mary-Claire and Lupski, James R} } @article {137, title = {Rare variants in the notch signaling pathway describe a novel type of autosomal recessive Klippel-Feil syndrome.}, journal = {Am J Med Genet A}, volume = {167A}, year = {2015}, month = {2015 Nov}, pages = {2795-9}, abstract = {

Klippel-Feil syndrome is a rare disorder represented by a subgroup of segmentation defects of the vertebrae and characterized by fusion of the cervical vertebrae, low posterior hairline, and short neck with limited motion. Both autosomal dominant and recessive inheritance patterns were reported in families with Klippel-Feil. Mutated genes for both dominant (GDF6 and GDF3) and recessive (MEOX1) forms of Klippel-Feil syndrome have been shown to be involved in somite development via transcription regulation and signaling pathways. Heterotaxy arises from defects in proteins that function in the development of left-right asymmetry of the developing embryo. We describe a consanguineous family with a male proband who presents with classical Klippel-Feil syndrome together with heterotaxy (situs inversus totalis). The present patient also had Sprengel{\textquoteright}s deformity, deformity of the sternum, and a solitary kidney. Using exome sequencing, we identified a homozygous frameshift mutation (c.299delT; p.L100fs) in RIPPLY2, a gene shown to play a crucial role in somitogenesis and participate in the Notch signaling pathway via negatively regulating Tbx6. Our data confirm RIPPLY2 as a novel gene for autosomal recessive Klippel-Feil syndrome, and in addition-from a mechanistic standpoint-suggest the possibility that mutations in RIPPLY2 could also lead to heterotaxy. {\textcopyright} 2015 Wiley Periodicals, Inc.

}, keywords = {Adolescent, Base Sequence, Female, Humans, Klippel-Feil Syndrome, Male, Molecular Sequence Data, Mutation, Pedigree, Radiography, Receptors, Notch, Signal Transduction, Spine}, issn = {1552-4833}, doi = {10.1002/ajmg.a.37263}, author = {Karaca, Ender and Yuregir, Ozge O and Bozdogan, Sevcan T and Aslan, Huseyin and Pehlivan, Davut and Jhangiani, Shalini N and Akdemir, Zeynep C and Gambin, Tomasz and Bayram, Yavuz and Atik, Mehmed M and Erdin, Serkan and Muzny, Donna and Gibbs, Richard A and Lupski, James R} } @article {218, title = {Whole-exome sequencing identifies homozygous GPR161 mutation in a family with pituitary stalk interruption syndrome.}, journal = {J Clin Endocrinol Metab}, volume = {100}, year = {2015}, month = {2015 Jan}, pages = {E140-7}, abstract = {

CONTEXT: Pituitary stalk interruption syndrome (PSIS) is a rare, congenital anomaly of the pituitary gland characterized by pituitary gland insufficiency, thin or discontinuous pituitary stalk, anterior pituitary hypoplasia, and ectopic positioning of the posterior pituitary gland (neurohypophysis). The clinical presentation of patients with PSIS varies from isolated growth hormone (GH) deficiency to combined pituitary insufficiency and accompanying extrapituitary findings. Mutations in HESX1, LHX4, OTX2, SOX3, and PROKR2 have been associated with PSIS in less than 5\% of cases; thus, the underlying genetic etiology for the vast majority of cases remains to be determined.

OBJECTIVE: We applied whole-exome sequencing (WES) to a consanguineous family with two affected siblings who have pituitary gland insufficiency and radiographic findings of hypoplastic (thin) pituitary gland, empty sella, ectopic neurohypophysis, and interrupted pitiutary stalk-characteristic clinical diagnostic findings of PSIS.

DESIGN AND PARTICIPANTS: WES was applied to two affected and one unaffected siblings.

RESULTS: WES of two affected and one unaffected sibling revealed a unique homozygous missense mutation in GPR161, which encodes the orphan G protein-coupled receptor 161, a protein responsible for transducing extracellular signals across the plasma membrane into the cell.

CONCLUSION: Mutations of GPR161 may be implicated as a potential novel cause of PSIS.

}, keywords = {Adolescent, Child, Preschool, Exome, Female, Genome-Wide Association Study, Humans, Hypopituitarism, Mutation, Pituitary Gland, Receptors, G-Protein-Coupled}, issn = {1945-7197}, doi = {10.1210/jc.2014-1984}, author = {Karaca, Ender and Buyukkaya, Ramazan and Pehlivan, Davut and Charng, Wu-Lin and Yaykasli, Kursat O and Bayram, Yavuz and Gambin, Tomasz and Withers, Marjorie and Atik, Mehmed M and Arslanoglu, Ilknur and Bolu, Semih and Erdin, Serkan and Buyukkaya, Ayla and Yaykasli, Emine and Jhangiani, Shalini N and Muzny, Donna M and Gibbs, Richard A and Lupski, James R} } @article {220, title = {A drosophila genetic resource of mutants to study mechanisms underlying human genetic diseases.}, journal = {Cell}, volume = {159}, year = {2014}, month = {2014 Sep 25}, pages = {200-214}, abstract = {

Invertebrate model systems are powerful tools for studying human disease owing to their genetic tractability and ease of screening. We conducted a mosaic genetic screen of lethal mutations on the Drosophila X chromosome to identify genes required for the development, function, and maintenance of the nervous system. We identified 165 genes, most of whose function has not been studied in vivo. In parallel, we investigated rare variant alleles in 1,929 human exomes from families with unsolved Mendelian disease. Genes that are essential in flies and have multiple human homologs were found to be likely to be associated with human diseases. Merging the human data sets with the fly genes allowed us to identify disease-associated mutations in six families and to provide insights into microcephaly associated with brain dysgenesis. This bidirectional synergism between fly genetics and human genomics facilitates the functional annotation of evolutionarily conserved genes involved in human health.

}, keywords = {Animals, Disease, Disease Models, Animal, Drosophila melanogaster, Genetic Testing, Humans, Inheritance Patterns, RNA Interference, X Chromosome}, issn = {1097-4172}, doi = {10.1016/j.cell.2014.09.002}, author = {Yamamoto, Shinya and Jaiswal, Manish and Charng, Wu-Lin and Gambin, Tomasz and Karaca, Ender and Mirzaa, Ghayda and Wiszniewski, Wojciech and Sandoval, Hector and Haelterman, Nele A and Xiong, Bo and Zhang, Ke and Bayat, Vafa and David, Gabriela and Li, Tongchao and Chen, Kuchuan and Gala, Upasana and Harel, Tamar and Pehlivan, Davut and Penney, Samantha and Vissers, Lisenka E L M and de Ligt, Joep and Jhangiani, Shalini N and Xie, Yajing and Tsang, Stephen H and Parman, Yesim and Sivaci, Merve and Battaloglu, Esra and Muzny, Donna and Wan, Ying-Wooi and Liu, Zhandong and Lin-Moore, Alexander T and Clark, Robin D and Curry, Cynthia J and Link, Nichole and Schulze, Karen L and Boerwinkle, Eric and Dobyns, William B and Allikmets, Rando and Gibbs, Richard A and Chen, Rui and Lupski, James R and Wangler, Michael F and Bellen, Hugo J} } @article {285, title = {Exonic duplication CNV of NDRG1 associated with autosomal-recessive HMSN-Lom/CMT4D.}, journal = {Genet Med}, volume = {16}, year = {2014}, month = {2014 May}, pages = {386-394}, abstract = {

PURPOSE: Copy-number variations as a mutational mechanism contribute significantly to human disease. Approximately one-half of the patients with Charcot-Marie-Tooth (CMT) disease have a 1.4 Mb duplication copy-number variation as the cause of their neuropathy. However, non-CMT1A neuropathy patients rarely have causative copy-number variations, and to date, autosomal-recessive disease has not been associated with copy-number variation as a mutational mechanism.

METHODS: We performed Agilent 8 {\texttimes} 60 K array comparative genomic hybridization on DNA from 12 recessive Turkish families with CMT disease. Additional molecular studies were conducted to detect breakpoint junctions and to evaluate gene expression levels in a family in which we detected an intragenic duplication copy-number variation.

RESULTS: We detected an ~6.25 kb homozygous intragenic duplication in NDRG1, a gene known to be causative for recessive HMSNL/CMT4D, in three individuals from a Turkish family with CMT neuropathy. Further studies showed that this intragenic copy-number variation resulted in a homozygous duplication of exons 6-8 that caused decreased mRNA expression of NDRG1.

CONCLUSION: Exon-focused high-resolution array comparative genomic hybridization enables the detection of copy-number variation carrier states in recessive genes, particularly small copy-number variations encompassing or disrupting single genes. In families for whom a molecular diagnosis has not been elucidated by conventional clinical assays, an assessment for copy-number variations in known CMT genes might be considered.

}, keywords = {Adult, Base Sequence, Cell Cycle Proteins, Charcot-Marie-Tooth Disease, Comparative Genomic Hybridization, DNA Copy Number Variations, Female, Gene Duplication, Gene Expression, Genes, Recessive, Humans, Intracellular Signaling Peptides and Proteins, Male, Mutation, Refsum Disease, Sequence Analysis, DNA, Turkey, Young Adult}, issn = {1530-0366}, doi = {10.1038/gim.2013.155}, author = {Okamoto, Yuji and Goksungur, Meryem Tuba and Pehlivan, Davut and Beck, Christine R and Gonzaga-Jauregui, Claudia and Muzny, Donna M and Atik, Mehmed M and Carvalho, Claudia M B and Matur, Zeliha and Bayraktar, Serife and Boone, Philip M and Akyuz, Kaya and Gibbs, Richard A and Battaloglu, Esra and Parman, Yesim and Lupski, James R} } @article {253, title = {Human CLP1 mutations alter tRNA biogenesis, affecting both peripheral and central nervous system function.}, journal = {Cell}, volume = {157}, year = {2014}, month = {2014 Apr 24}, pages = {636-50}, abstract = {

CLP1 is a RNA kinase involved in tRNA splicing. Recently, CLP1 kinase-dead mice were shown to display a neuromuscular disorder with loss of motor neurons and muscle paralysis. Human genome analyses now identified a CLP1 homozygous missense mutation (p.R140H) in five unrelated families, leading to a loss of CLP1 interaction with the tRNA splicing endonuclease (TSEN) complex, largely reduced pre-tRNA cleavage activity, and accumulation of linear tRNA introns. The affected individuals develop severe motor-sensory defects, cortical dysgenesis, and microcephaly. Mice carrying kinase-dead CLP1 also displayed microcephaly and reduced cortical brain volume due to the enhanced cell death of neuronal progenitors that is associated with reduced numbers of cortical neurons. Our data elucidate a neurological syndrome defined by CLP1 mutations that impair tRNA splicing. Reduction of a founder mutation to homozygosity illustrates the importance of rare variations in disease and supports the clan genomics hypothesis.

}, keywords = {Abnormalities, Multiple, Animals, Central Nervous System Diseases, Cerebrum, Child, Preschool, Endoribonucleases, Female, Fibroblasts, Humans, Infant, Male, Mice, Mice, Inbred CBA, Microcephaly, Mutation, Missense, Nuclear Proteins, Peripheral Nervous System Diseases, Phosphotransferases, RNA, Transfer, Transcription Factors}, issn = {1097-4172}, doi = {10.1016/j.cell.2014.02.058}, author = {Karaca, Ender and Weitzer, Stefan and Pehlivan, Davut and Shiraishi, Hiroshi and Gogakos, Tasos and Hanada, Toshikatsu and Jhangiani, Shalini N and Wiszniewski, Wojciech and Withers, Marjorie and Campbell, Ian M and Erdin, Serkan and Isikay, Sedat and Franco, Luis M and Gonzaga-Jauregui, Claudia and Gambin, Tomasz and Gelowani, Violet and Hunter, Jill V and Yesil, G{\"o}zde and Koparir, Erkan and Yilmaz, Sarenur and Brown, Miguel and Briskin, Daniel and Hafner, Markus and Morozov, Pavel and Farazi, Thalia A and Bernreuther, Christian and Glatzel, Markus and Trattnig, Siegfried and Friske, Joachim and Kronnerwetter, Claudia and Bainbridge, Matthew N and Gezdirici, Alper and Seven, Mehmet and Muzny, Donna M and Boerwinkle, Eric and Ozen, Mustafa and Clausen, Tim and Tuschl, Thomas and Yuksel, Adnan and Hess, Andreas and Gibbs, Richard A and Martinez, Javier and Penninger, Josef M and Lupski, James R} } @article {243, title = {Monoallelic and biallelic mutations in MAB21L2 cause a spectrum of major eye malformations.}, journal = {Am J Hum Genet}, volume = {94}, year = {2014}, month = {2014 Jun 05}, pages = {915-23}, abstract = {

We identified four different missense mutations in the single-exon gene MAB21L2 in eight individuals with bilateral eye malformations from five unrelated families via three independent exome sequencing projects. Three mutational events altered the same amino acid (Arg51), and two were identical de novo mutations (c.151C>T [p.Arg51Cys]) in unrelated children with bilateral anophthalmia, intellectual disability, and rhizomelic skeletal dysplasia. c.152G>A (p.Arg51His) segregated with autosomal-dominant bilateral colobomatous microphthalmia in a large multiplex family. The fourth heterozygous mutation (c.145G>A [p.Glu49Lys]) affected an amino acid within two residues of Arg51 in an adult male with bilateral colobomata. In a fifth family, a homozygous mutation (c.740G>A [p.Arg247Gln]) altering a different region of the protein was identified in two male siblings with bilateral retinal colobomata. In mouse embryos, Mab21l2 showed strong expression in the developing eye, pharyngeal arches, and limb bud. As predicted by structural homology, wild-type MAB21L2 bound single-stranded RNA, whereas this activity was lost in all altered forms of the protein. MAB21L2 had no detectable nucleotidyltransferase activity in~vitro, and its function remains unknown. Induced expression of wild-type MAB21L2 in human embryonic kidney 293 cells increased phospho-ERK (pERK1/2) signaling. Compared to the wild-type and p.Arg247Gln proteins, the proteins with the Glu49 and Arg51 variants had increased stability. Abnormal persistence of pERK1/2 signaling in MAB21L2-expressing cells during development is a plausible pathogenic mechanism for the heterozygous mutations. The phenotype associated with the homozygous mutation might be a consequence of complete loss of MAB21L2 RNA binding, although the cellular function of this interaction remains unknown.

}, keywords = {Adult, Alleles, Animals, Anophthalmos, Brain Diseases, Metabolic, Inborn, Coloboma, Corneal Opacity, Exome, Eye Proteins, Female, Gene Expression, HEK293 Cells, Heterozygote, Homozygote, Humans, Intellectual Disability, Intracellular Signaling Peptides and Proteins, Male, Mice, Microcephaly, Microphthalmos, Mutation, Missense, Pedigree, Phenotype, Protein Conformation, Signal Transduction}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2014.05.005}, author = {Rainger, Joe and Pehlivan, Davut and Johansson, Stefan and Bengani, Hemant and Sanchez-Pulido, Luis and Williamson, Kathleen A and Ture, Mehmet and Barker, Heather and Rosendahl, Karen and Spranger, J{\"u}rgen and Horn, Denise and Meynert, Alison and Floyd, James A B and Prescott, Trine and Anderson, Carl A and Rainger, Jacqueline K and Karaca, Ender and Gonzaga-Jauregui, Claudia and Jhangiani, Shalini and Muzny, Donna M and Seawright, Anne and Soares, Dinesh C and Kharbanda, Mira and Murday, Victoria and Finch, Andrew and Gibbs, Richard A and van Heyningen, Veronica and Taylor, Martin S and Yakut, Tahsin and Knappskog, Per M and Hurles, Matthew E and Ponting, Chris P and Lupski, James R and Houge, Gunnar and FitzPatrick, David R} } @article {233, title = {Whole exome sequencing identifies three novel mutations in ANTXR1 in families with GAPO syndrome.}, journal = {Am J Med Genet A}, volume = {164A}, year = {2014}, month = {2014 Sep}, pages = {2328-34}, abstract = {

GAPO syndrome (OMIM$\#$230740) is the acronym for growth retardation, alopecia, pseudoanodontia, and optic atrophy. About 35 cases have been reported, making it among one of the rarest recessive conditions. Distinctive craniofacial features including alopecia, rarefaction of eyebrows and eyelashes, frontal bossing, high forehead, mid-facial hypoplasia, hypertelorism, and thickened eyelids and lips make GAPO syndrome a clinically recognizable phenotype. While this genomic study was in progress mutations in ANTXR1 were reported to cause GAPO syndrome. In our study we performed whole exome sequencing (WES) for five affected individuals from three Turkish kindreds segregating the GAPO trait. Exome sequencing analysis identified three novel homozygous mutations including; one frame-shift (c.1220_1221insT; p.Ala408Cysfs*2), one splice site (c.411A>G; p.Gln137Gln), and one non-synonymous (c.1150G>A; p.Gly384Ser) mutation in the ANTXR1 gene. Our studies expand the allelic spectrum in this rare condition and potentially provide insight into the role of ANTXR1 in the regulation of the extracellular matrix.

}, keywords = {Adolescent, Adult, Alopecia, Anodontia, Base Sequence, Child, Chromosome Segregation, DNA Mutational Analysis, Exome, Facies, Family, Female, Growth Disorders, Humans, Male, Molecular Sequence Data, Mutation, Neoplasm Proteins, Optic Atrophies, Hereditary, Pedigree, Protein Structure, Tertiary, Receptors, Cell Surface}, issn = {1552-4833}, doi = {10.1002/ajmg.a.36678}, author = {Bayram, Yavuz and Pehlivan, Davut and Karaca, Ender and Gambin, Tomasz and Jhangiani, Shalini N and Erdin, Serkan and Gonzaga-Jauregui, Claudia and Wiszniewski, Wojciech and Muzny, Donna and Elcioglu, Nursel H and Yildirim, M Selman and Bozkurt, Banu and Zamani, Ayse Gul and Boerwinkle, Eric and Gibbs, Richard A and Lupski, James R} } @article {272, title = {Whole-exome sequencing links TMCO1 defect syndrome with cerebro-facio-thoracic dysplasia.}, journal = {Eur J Hum Genet}, volume = {22}, year = {2014}, month = {2014 Sep}, pages = {1145-8}, abstract = {

Whole-exome sequencing (WES) is a type of disruptive technology that has tremendous influence on human and clinical genetics research. An efficient and cost-effective method, WES is now widely used as a diagnostic tool for identifying the molecular basis of genetic syndromes that are often challenging to diagnose. Here we report a patient with a clinical diagnosis of cerebro-facio-thoracic dysplasia (CFTD; MIM$\#$213980) in whom we identified a homozygous splice-site mutation in the transmembrane and coiled-coil domains 1 (TMCO1) gene using WES. TMCO1 mutations cause craniofacial dysmorphism, skeletal anomalies characterized by multiple malformations of the vertebrae and ribs, and intellectual disability (MIM$\#$614132). A retrospective review revealed that clinical manifestations of both syndromes are very similar and overlap remarkably. We propose that mutations of TMCO1 are not only responsible for craniofacial dysmorphism, skeletal anomalies and mental retardation syndrome but also for CFTD.

}, keywords = {Abnormalities, Multiple, Exome, Humans, Infant, Intellectual Disability, Male, Membrane Proteins, Mutation, Protein Isoforms}, issn = {1476-5438}, doi = {10.1038/ejhg.2013.291}, author = {Pehlivan, Davut and Karaca, Ender and Aydin, Hatip and Beck, Christine R and Gambin, Tomasz and Muzny, Donna M and Bilge Geckinli, B and Karaman, Ali and Jhangiani, Shalini N and Gibbs, Richard A and Lupski, James R} } @article {296, title = {ARMC4 mutations cause primary ciliary dyskinesia with randomization of left/right body asymmetry.}, journal = {Am J Hum Genet}, volume = {93}, year = {2013}, month = {2013 Aug 08}, pages = {357-67}, abstract = {

The motive forces for ciliary movement are generated by large multiprotein complexes referred to as outer dynein arms (ODAs), which are preassembled in the cytoplasm prior to transport to the ciliary axonemal compartment. In humans, defects in structural components, docking complexes, or cytoplasmic assembly factors can cause primary ciliary dyskinesia (PCD), a disorder characterized by chronic airway disease and defects in laterality. By using combined high resolution copy-number variant and mutation analysis, we identified ARMC4 mutations in twelve PCD individuals whose cells showed reduced numbers of ODAs and severely impaired ciliary beating. Transient suppression in zebrafish and analysis of an ENU mouse mutant confirmed in both model organisms that ARMC4 is critical for left-right patterning. We demonstrate that ARMC4 is an axonemal protein that is necessary for proper targeting and anchoring of ODAs.

}, keywords = {Amino Acid Sequence, Animals, Armadillo Domain Proteins, Axoneme, Body Patterning, Cilia, DNA Copy Number Variations, DNA Mutational Analysis, Dyneins, Gene Expression Regulation, Humans, Kartagener Syndrome, Mice, Microtubule-Associated Proteins, Molecular Sequence Data, Mutation, Respiratory System, Zebrafish}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2013.06.009}, author = {Hjeij, Rim and Lindstrand, Anna and Francis, Richard and Zariwala, Maimoona A and Liu, Xiaoqin and Li, You and Damerla, Rama and Dougherty, Gerard W and Abouhamed, Marouan and Olbrich, Heike and Loges, Niki T and Pennekamp, Petra and Davis, Erica E and Carvalho, Claudia M B and Pehlivan, Davut and Werner, Claudius and Raidt, Johanna and K{\"o}hler, Gabriele and H{\"a}ffner, Karsten and Reyes-Mugica, Miguel and Lupski, James R and Leigh, Margaret W and Rosenfeld, Margaret and Morgan, Lucy C and Knowles, Michael R and Lo, Cecilia W and Katsanis, Nicholas and Omran, Heymut} } @article {287, title = {Mutations in VRK1 associated with complex motor and sensory axonal neuropathy plus microcephaly.}, journal = {JAMA Neurol}, volume = {70}, year = {2013}, month = {2013 Dec}, pages = {1491-8}, abstract = {

IMPORTANCE: Patients with rare diseases and complex clinical presentations represent a challenge for clinical diagnostics. Genomic approaches are allowing the identification of novel variants in genes for very rare disorders, enabling a molecular diagnosis. Genomics is also revealing a phenotypic expansion whereby the full spectrum of clinical expression conveyed by mutant alleles at a locus can be better appreciated.

OBJECTIVE: To elucidate the molecular cause of a complex neuropathy phenotype in 3 patients by applying genomic sequencing strategies.

DESIGN, SETTING, AND PARTICIPANTS: Three affected individuals from 2 unrelated families presented with a complex neuropathy phenotype characterized by axonal sensorimotor neuropathy and microcephaly. They were recruited into the Centers for Mendelian Genomics research program to identify the molecular cause of their phenotype. Whole-genome, targeted whole-exome sequencing, and high-resolution single-nucleotide polymorphism arrays were performed in genetics clinics of tertiary care pediatric hospitals and biomedical research institutions.

MAIN OUTCOMES AND MEASURES: Whole-genome and whole-exome sequencing identified the variants responsible for the patients{\textquoteright} clinical phenotype.

RESULTS: We identified compound heterozygous alleles in 2 affected siblings from 1 family and a homozygous nonsense variant in the third unrelated patient in the vaccinia-related kinase 1 gene (VRK1). In the latter subject, we found a common haplotype on which the nonsense mutation occurred and that segregates in the Ashkenazi Jewish population.

CONCLUSIONS AND RELEVANCE: We report the identification of disease-causing alleles in 3 children from 2 unrelated families with a previously uncharacterized complex axonal motor and sensory neuropathy accompanied by severe nonprogressive microcephaly and cerebral dysgenesis. Our data raise the question of whether VRK1 mutations disturb cell cycle progression and may result in apoptosis of cells in the nervous system. The application of unbiased genomic approaches allows the identification of potentially pathogenic mutations in unsuspected genes in highly genetically heterogeneous and uncharacterized neurological diseases.

}, keywords = {Child, Child, Preschool, DNA Mutational Analysis, Female, Genotype, Hereditary Sensory and Motor Neuropathy, Humans, Infant, Intracellular Signaling Peptides and Proteins, Magnetic Resonance Imaging, Male, Microcephaly, Mutation, Neural Conduction, Polymorphism, Single Nucleotide, Protein-Serine-Threonine Kinases}, issn = {2168-6157}, doi = {10.1001/jamaneurol.2013.4598}, author = {Gonzaga-Jauregui, Claudia and Lotze, Timothy and Jamal, Leila and Penney, Samantha and Campbell, Ian M and Pehlivan, Davut and Hunter, Jill V and Woodbury, Suzanne L and Raymond, Gerald and Adesina, Adekunle M and Jhangiani, Shalini N and Reid, Jeffrey G and Muzny, Donna M and Boerwinkle, Eric and Lupski, James R and Gibbs, Richard A and Wiszniewski, Wojciech} } @article {288, title = {Replicative mechanisms for CNV formation are error prone.}, journal = {Nat Genet}, volume = {45}, year = {2013}, month = {2013 Nov}, pages = {1319-26}, abstract = {

We investigated 67 breakpoint junctions of gene copy number gains in 31 unrelated subjects. We observed a strikingly high frequency of small deletions and insertions (29\%) apparently originating from polymerase slippage events, in addition to frameshifts and point mutations in homonucleotide runs (13\%), at or flanking the breakpoint junctions of complex copy number variants. These single-nucleotide variants were generated concomitantly with the de novo complex genomic rearrangement (CGR) event. Our findings implicate low-fidelity, error-prone DNA polymerase activity in synthesis associated with DNA repair mechanisms as the cause of local increase in point mutation burden associated with human CGR.

}, keywords = {Base Sequence, DNA Breaks, DNA Copy Number Variations, DNA Repair, DNA Replication, Frameshift Mutation, Gene Rearrangement, Genetic Variation, Genotype, Humans, Sequence Analysis, DNA, Sequence Deletion}, issn = {1546-1718}, doi = {10.1038/ng.2768}, author = {Carvalho, Claudia M B and Pehlivan, Davut and Ramocki, Melissa B and Fang, Ping and Alleva, Benjamin and Franco, Luis M and Belmont, John W and Hastings, P J and Lupski, James R} }