@article {826, title = {Molecular diagnosis in recessive pediatric neurogenetic disease can help reduce disease recurrence in families.}, journal = {BMC Med Genomics}, volume = {13}, year = {2020}, month = {2020 05 13}, pages = {68}, abstract = {

BACKGROUND: The causes for thousands of individually rare recessive diseases have been discovered since the adoption of next generation sequencing (NGS). Following the molecular diagnosis in older children in a family, parents could use this information to opt for fetal genotyping in subsequent pregnancies, which could inform decisions about elective termination of pregnancy. The use of NGS diagnostic sequencing in families has not been demonstrated to yield benefit in subsequent pregnancies to reduce recurrence. Here we evaluated whether genetic diagnosis in older children in families supports reduction in recurrence of recessive neurogenetic disease.

METHODS: Retrospective study involving families with a child with a recessive pediatric brain disease (rPBD) that underwent NGS-based molecular diagnosis. Prenatal molecular testing was offered to couples in which a molecular diagnosis was made, to help couples seeking to prevent recurrence. With this information, families made decisions about elective termination. Pregnancies that were carried to term were assessed for the health of child and mother, and compared with historic recurrence risk of recessive disease.

RESULTS: Between 2010 and 2016, 1172 families presented with a child a likely~rPBD, 526 families received a molecular diagnosis, 91 families returned to the clinic with 101 subsequent pregnancies, and 84 opted for fetal genotyping. Sixty tested negative for recurrence for the biallelic mutation~in the fetus, and all, except for one spontaneous abortion, carried to term, and were unaffected at follow-up. Of 24 that genotyped positive~for~the biallelic mutation, 16 were electively terminated, and 8 were carried to term and showed features of disease similar to that of the older~affected sibling(s). Among the 101 pregnancies, disease recurrence in living offspring deviated from the expected 25\% to the observed 12\% ([95\% CI 0{\textperiodcentered}04 to 0{\textperiodcentered}20], p = 0{\textperiodcentered}011).

CONCLUSIONS: Molecular diagnosis in an older child, coupled with prenatal fetal genotyping in subsequent pregnancies and genetic counselling, allows families to make informed decisions to reduce recessive neurogenetic disease recurrence.

}, keywords = {Child, Preschool, Female, Genes, Recessive, Genetic Markers, Genetic Predisposition to Disease, Genetic Testing, Genotype, High-Throughput Nucleotide Sequencing, Humans, Infant, Infant, Newborn, Male, Mutation, Nervous System Diseases, Pedigree, Pregnancy, Prenatal Diagnosis, Recurrence, Retrospective Studies}, issn = {1755-8794}, doi = {10.1186/s12920-020-0714-1}, author = {Issa, Mahmoud Y and Chechlacz, Zinayida and Stanley, Valentina and George, Renee D and McEvoy-Venneri, Jennifer and Belandres, Denice and Elbendary, Hasnaa M and Gaber, Khaled R and Nabil, Ahmed and Abdel-Hamid, Mohamed S and Zaki, MAH S and Gleeson, Joseph G} } @article {571, title = {Recessive mutations in muscle-specific isoforms of FXR1 cause congenital multi-minicore myopathy.}, journal = {Nat Commun}, volume = {10}, year = {2019}, month = {2019 02 15}, pages = {797}, abstract = {

FXR1 is an alternatively spliced gene that encodes RNA binding proteins (FXR1P) involved in muscle development. In contrast to other tissues, cardiac and skeletal muscle express two FXR1P isoforms that incorporate an additional exon-15. We report that recessive mutations in this particular exon of FXR1 cause congenital multi-minicore myopathy in humans and mice. Additionally, we show that while Myf5-dependent depletion of all FXR1P isoforms is neonatal lethal, mice carrying mutations in exon-15 display non-lethal myopathies which vary in severity depending on the specific effect of each mutation on the protein.

}, keywords = {Animals, Cells, Cultured, Exons, Gene Expression, Genes, Recessive, Genetic Predisposition to Disease, HEK293 Cells, HeLa Cells, Humans, Mice, Transgenic, Muscle, Skeletal, Mutation, Myopathies, Structural, Congenital, Ophthalmoplegia, RNA-Binding Proteins, Ryanodine Receptor Calcium Release Channel}, issn = {2041-1723}, doi = {10.1038/s41467-019-08548-9}, author = {Esta{\~n}, Mar{\'\i}a Cristina and Fern{\'a}ndez-N{\'u}{\~n}ez, Elisa and Zaki, Maha S and Esteban, Mar{\'\i}a Isabel and Donkervoort, Sandra and Hawkins, Cynthia and Caparros-Martin, Jos{\'e} A and Saade, Dimah and Hu, Ying and Bolduc, Veronique and Chao, Katherine Ru-Yui and Nevado, Juli{\'a}n and Lamuedra, Ana and Largo, Raquel and Herrero-Beaumont, Gabriel and Regadera, Javier and Hernandez-Chico, Concepci{\'o}n and Tizzano, Eduardo F and Martinez-Glez, Victor and Carvajal, Jaime J and Zong, Ruiting and Nelson, David L and Otaify, Ghada A and Temtamy, Samia and Aglan, Mona and Issa, Mahmoud and B{\"o}nnemann, Carsten G and Lapunzina, Pablo and Yoon, Grace and Ruiz-Perez, Victor L} } @article {652, title = {Variants in KIAA0825 underlie autosomal recessive postaxial polydactyly.}, journal = {Hum Genet}, volume = {138}, year = {2019}, month = {2019 Jun}, pages = {593-600}, abstract = {

Postaxial polydactyly (PAP) is a common limb malformation that often leads to cosmetic and functional complications. Molecular evaluation of polydactyly can serve as a tool to elucidate genetic and signaling pathways that regulate limb development, specifically, the anterior-posterior specification of the limb. To date, only five genes have been identified for nonsyndromic PAP: FAM92A, GLI1, GLI3, IQCE and ZNF141. In this study, two Pakistani multiplex consanguineous families with autosomal recessive nonsyndromic PAP were clinically and molecularly evaluated. From both pedigrees, a DNA sample from an affected member underwent exome sequencing. In each family, we identified a segregating frameshift (c.591dupA [p.(Q198Tfs*21)]) and nonsense variant (c.2173A > T [p.(K725*)]) in KIAA0825 (also known as C5orf36). Although KIAA0825 encodes a protein of unknown function, it has been demonstrated that its murine ortholog is expressed during limb development. Our data contribute to the establishment of a catalog of genes important in limb patterning, which can aid in diagnosis and obtaining a better understanding of the biology of polydactyly.

}, keywords = {Animals, Consanguinity, Family Health, Female, Fingers, Genes, Recessive, Genetic Predisposition to Disease, Genotype, Humans, Intracellular Signaling Peptides and Proteins, Male, Mice, Inbred C57BL, Mutation, Pedigree, Phenotype, Polydactyly, Toes, Whole Exome Sequencing}, issn = {1432-1203}, doi = {10.1007/s00439-019-02000-0}, author = {Ullah, Irfan and Kakar, Naseebullah and Schrauwen, Isabelle and Hussain, Shabir and Chakchouk, Imen and Liaqat, Khurram and Acharya, Anushree and Wasif, Naveed and Santos-Cortez, Regie Lyn P and Khan, Saadullah and Aziz, Abdul and Lee, Kwanghyuk and Couthouis, Julien and Horn, Denise and Kragesteen, Bj{\o}rt K and Spielmann, Malte and Thiele, Holger and Nickerson, Deborah A and Bamshad, Michael J and Gitler, Aaron D and Ahmad, Jamil and Ansar, Muhammad and Borck, Guntram and Ahmad, Wasim and Leal, Suzanne M} } @article {512, title = {Confirmation of the Role of DHX38 in the Etiology of Early-Onset Retinitis Pigmentosa.}, journal = {Invest Ophthalmol Vis Sci}, volume = {59}, year = {2018}, month = {2018 09 04}, pages = {4552-4557}, abstract = {

Purpose: Retinitis pigmentosa (RP) is a genetically heterogeneous trait with autosomal-recessive (ar) inheritance underlying 50\% of genetic disease cases. Sixty-one arRP genes have been identified, and recently, DHX38 has been reported as a potential candidate gene for arRP with only a single family reported with a variant of unknown significance. We identified a missense variant in DHX38 that co-segregates with the arRP phenotype in two Pakistani families confirming the involvement of DHX38 in the etiology of early-onset RP.

Methods: Exome sequencing was performed using two DNA samples from affected members of Pakistani families (MA88 and MA157) with early onset arRP. Sanger sequencing of DNA samples from all family members confirmed the segregation of candidate variant within both families.

Results: A novel missense DHX38 variant c.971G>A; p.(Arg324Gln) was identified which segregates with the arRP phenotype and yielded a logarithm of the odds (LOD) score of 5.0 and 4.3 for families MA88 and MA157, respectively. This variant is predicted to be conserved and deleterious by several bioinformatics tools.

Conclusions: We identified a second deleterious DHX38 variant that segregates with arRP in two families, providing additional evidence that DHX38 is involved in RP etiology. DHX38 encodes for pre-mRNA splicing factor PRP16, which is important in catalyzing pre-mRNA splicing.

}, keywords = {Adolescent, Adult, Cataract, Computational Biology, DEAD-box RNA Helicases, Female, Genes, Recessive, Genetic Association Studies, Genetic Linkage, Humans, Male, Mutation, Missense, Nucleotide Mapping, Ophthalmoscopy, Pedigree, Retinitis Pigmentosa, RNA Splicing Factors, Sequence Analysis, DNA, Whole Exome Sequencing, Young Adult}, issn = {1552-5783}, doi = {10.1167/iovs.18-23849}, author = {Latif, Zahid and Chakchouk, Imen and Schrauwen, Isabelle and Lee, Kwanghyuk and Santos-Cortez, Regie Lyn P and Abbe, Izoduwa and Acharya, Anushree and Jarral, Afeefa and Ali, Imran and Ullah, Ehsan and Khan, Muhammad Nasim and Ali, Ghazanfar and Tahir, Tufail Hussain and Bamshad, Michael J and Nickerson, Deborah A and Ahmad, Wasim and Ansar, Muhammad and Leal, Suzanne M} } @article {432, title = {Nemaline myopathy and distal arthrogryposis associated with an autosomal recessive~TNNT3~splice variant.}, journal = {Hum Mutat}, volume = {39}, year = {2018}, month = {2018 03}, pages = {383-388}, abstract = {

A male neonate presented with severe weakness, hypotonia, contractures and congenital scoliosis. Skeletal muscle specimens showed marked atrophy and degeneration of fast fibers with striking nemaline rods and hypertrophy of slow fibers that were ultrastructurally normal. A neuromuscular gene panel identified a homozygous essential splice variant in TNNT3 (chr11:1956150G~>~A, NM_006757.3:c.681+1G~>~A). TNNT3 encodes skeletal troponin-T and is associated with autosomal dominant distal arthrogryposis. TNNT3 has not previously been associated with nemaline myopathy (NM), a rare congenital myopathy linked to defects in proteins associated with thin filament structure and regulation. cDNA studies confirmed pathogenic consequences of the splice variant, eliciting exon-skipping and intron retention events leading to a frameshift. Western blot showed deficiency of troponin-T protein with secondary loss of troponin-I . We establish a homozygous splice variant in TNNT3 as the likely cause of severe congenital NM with distal arthrogryposis, characterized by specific involvement of Type-2 fibers and deficiency of troponin-T .

}, keywords = {Arthrogryposis, Genes, Recessive, Humans, Infant, Infant, Newborn, Male, Myopathies, Nemaline, RNA Splice Sites, RNA Splicing, RNA, Messenger, Troponin T}, issn = {1098-1004}, doi = {10.1002/humu.23385}, author = {Sandaradura, Sarah A and Bournazos, Adam and Mallawaarachchi, Amali and Cummings, Beryl B and Waddell, Leigh B and Jones, Kristi J and Troedson, Christopher and Sudarsanam, Annapurna and Nash, Benjamin M and Peters, Gregory B and Algar, Elizabeth M and MacArthur, Daniel G and North, Kathryn N and Brammah, Susan and Charlton, Amanda and Laing, Nigel G and Wilson, Meredith J and Davis, Mark R and Cooper, Sandra T} } @article {498, title = {Novel candidate genes and variants underlying autosomal recessive neurodevelopmental disorders with intellectual disability.}, journal = {Hum Genet}, volume = {137}, year = {2018}, month = {2018 Sep}, pages = {735-752}, abstract = {

Identification of Mendelian genes for neurodevelopmental disorders using exome sequencing to study autosomal recessive (AR) consanguineous pedigrees has been highly successful. To identify causal variants for syndromic and non-syndromic intellectual disability (ID), exome sequencing was performed using DNA samples from 22 consanguineous Pakistani families with ARID, of which 21 have additional phenotypes including microcephaly. To aid in variant identification, homozygosity mapping and linkage analysis were performed. DNA samples from affected family member(s) from every pedigree underwent exome sequencing. Identified rare damaging exome variants were tested for co-segregation with ID using Sanger sequencing. For seven ARID families, variants were identified in genes not previously associated with ID, including: EI24, FXR1 and TET3 for which knockout mouse models have brain defects; and CACNG7 and TRAPPC10 where cell studies suggest roles in important neural pathways. For two families, the novel ARID genes CARNMT1 and GARNL3 lie within previously reported ID microdeletion regions. We also observed homozygous variants in two ID candidate genes, GRAMD1B and TBRG1, for which each has been previously reported in a single family. An additional 14 families have homozygous variants in established ID genes, of which 11 variants are novel. All ARID genes have increased expression in specific structures of the developing and adult human brain and 91\% of the genes are differentially expressed in utero or during early childhood. The identification of novel ARID candidate genes and variants adds to the knowledge base that is required to further understand human brain function and development.

}, keywords = {Adult, Consanguinity, Family, Female, Genes, Recessive, Genetic Markers, Humans, Intellectual Disability, Male, Middle Aged, Mutation, Neurodevelopmental Disorders, Pedigree}, issn = {1432-1203}, doi = {10.1007/s00439-018-1928-6}, author = {Santos-Cortez, Regie Lyn P and Khan, Valeed and Khan, Falak Sher and Mughal, Zaib-Un-Nisa and Chakchouk, Imen and Lee, Kwanghyuk and Rasheed, Memoona and Hamza, Rifat and Acharya, Anushree and Ullah, Ehsan and Saqib, Muhammad Arif Nadeem and Abbe, Izoduwa and Ali, Ghazanfar and Hassan, Muhammad Jawad and Khan, Saadullah and Azeem, Zahid and Ullah, Irfan and Bamshad, Michael J and Nickerson, Deborah A and Schrauwen, Isabelle and Ahmad, Wasim and Ansar, Muhammad and Leal, Suzanne M} } @article {485, title = {A variant in LMX1A causes autosomal recessive severe-to-profound hearing impairment.}, journal = {Hum Genet}, volume = {137}, year = {2018}, month = {2018 Jul}, pages = {471-478}, abstract = {

Hereditary hearing impairment is a common sensory disorder that is genetically and phenotypically heterogeneous. In this study, we used a homozygosity mapping and exome sequencing strategy to study a consanguineous Pakistani family with autosomal recessive severe-to-profound hearing impairment. This led to the identification of a missense variant (p.Ile369Thr) in the LMX1A gene affecting a conserved residue in the C-terminus of the protein, which was predicted damaging by an in silico bioinformatics analysis. The p.Ile369Thr variant disrupts several C-terminal and homeodomain residue interactions, including an interaction with homeodomain residue p.Val241 that was previously found to be involved in autosomal dominant progressive HI. LIM-homeodomain factor Lmx1a is expressed in the inner ear through development, shows a progressive restriction to non-sensory epithelia, and is important in the separation of the sensory and non-sensory domains in the inner ear. Homozygous Lmx1a mutant mice (Dreher) are deaf with dysmorphic ears with an abnormal morphogenesis and fused and misshapen sensory organs; however, computed tomography performed on a hearing-impaired family member did not reveal any cochleovestibular malformations. Our results suggest that LMX1A is involved in both human autosomal recessive and dominant sensorineural hearing impairment.

}, keywords = {Adolescent, Adult, Animals, Child, Disease Models, Animal, Ear, Inner, Female, Genes, Dominant, Genes, Recessive, Hearing Loss, Hearing Loss, Sensorineural, Homozygote, Humans, LIM-Homeodomain Proteins, Male, Mice, Mutation, Missense, Pedigree, Transcription Factors, Whole Exome Sequencing}, issn = {1432-1203}, doi = {10.1007/s00439-018-1899-7}, author = {Schrauwen, Isabelle and Chakchouk, Imen and Liaqat, Khurram and Jan, Abid and Nasir, Abdul and Hussain, Shabir and Nickerson, Deborah A and Bamshad, Michael J and Ullah, Asmat and Ahmad, Wasim and Leal, Suzanne M} } @article {638, title = {A defect in myoblast fusion underlies Carey-Fineman-Ziter syndrome.}, journal = {Nat Commun}, volume = {8}, year = {2017}, month = {2017 07 06}, pages = {16077}, abstract = {

Multinucleate cellular syncytial formation is a hallmark of skeletal muscle differentiation. Myomaker, encoded by Mymk (Tmem8c), is a well-conserved plasma membrane protein required for myoblast fusion to form multinucleated myotubes in mouse, chick, and zebrafish. Here, we report that autosomal recessive mutations in MYMK (OMIM 615345) cause Carey-Fineman-Ziter syndrome in humans (CFZS; OMIM 254940) by reducing but not eliminating MYMK function. We characterize MYMK-CFZS as a congenital myopathy with marked facial weakness and additional clinical and pathologic features that distinguish it from other congenital neuromuscular syndromes. We show that a heterologous cell fusion assay in vitro and allelic complementation experiments in mymk knockdown and mymk zebrafish in vivo can differentiate between MYMK wild type, hypomorphic and null alleles. Collectively, these data establish that MYMK activity is necessary for normal muscle development and maintenance in humans, and expand the spectrum of congenital myopathies to include cell-cell fusion deficits.

}, keywords = {Adult, Amino Acid Sequence, Animals, Cell Fusion, Child, Disease Models, Animal, Embryo, Nonmammalian, Female, Gene Expression, Genes, Recessive, Genetic Complementation Test, Humans, Infant, Male, Membrane Proteins, Mobius Syndrome, Morphogenesis, Muscle Proteins, Muscle, Skeletal, Muscular Diseases, Mutation, Myoblasts, Pedigree, Pierre Robin Syndrome, Sequence Alignment, Sequence Homology, Amino Acid, Zebrafish, Zebrafish Proteins}, issn = {2041-1723}, doi = {10.1038/ncomms16077}, author = {Di Gioia, Silvio Alessandro and Connors, Samantha and Matsunami, Norisada and Cannavino, Jessica and Rose, Matthew F and Gilette, Nicole M and Artoni, Pietro and de Macena Sobreira, Nara Lygia and Chan, Wai-Man and Webb, Bryn D and Robson, Caroline D and Cheng, Long and Van Ryzin, Carol and Ramirez-Martinez, Andres and Mohassel, Payam and Leppert, Mark and Scholand, Mary Beth and Grunseich, Christopher and Ferreira, Carlos R and Hartman, Tyler and Hayes, Ian M and Morgan, Tim and Markie, David M and Fagiolini, Michela and Swift, Amy and Chines, Peter S and Speck-Martins, Carlos E and Collins, Francis S and Jabs, Ethylin Wang and B{\"o}nnemann, Carsten G and Olson, Eric N and Carey, John C and Robertson, Stephen P and Manoli, Irini and Engle, Elizabeth C} } @article {340, title = {Loss-of-Function Mutations in YY1AP1 Lead to Grange Syndrome and a Fibromuscular Dysplasia-Like Vascular Disease.}, journal = {Am J Hum Genet}, volume = {100}, year = {2017}, month = {2017 Jan 05}, pages = {21-30}, abstract = {

Fibromuscular dysplasia (FMD) is a heterogeneous group of non-atherosclerotic and non-inflammatory arterial diseases that primarily involves the renal and cerebrovascular arteries. Grange syndrome is an autosomal-recessive condition characterized by severe and early-onset vascular disease similar to FMD and variable penetrance of brachydactyly, syndactyly, bone fragility, and learning disabilities. Exome-sequencing analysis of DNA from three affected siblings with Grange syndrome identified compound heterozygous nonsense variants in YY1AP1, and homozygous nonsense or frameshift YY1AP1 variants were subsequently identified in additional unrelated probands with Grange syndrome. YY1AP1 encodes yin yang 1 (YY1)-associated protein 1 and is an activator of the YY1 transcription factor. We determined that YY1AP1 localizes to the nucleus and is a component of the INO80 chromatin remodeling complex, which is responsible for transcriptional regulation, DNA repair, and replication. Molecular studies revealed that loss of YY1AP1 in vascular smooth muscle cells leads to cell cycle arrest with decreased proliferation and increased levels of the cell cycle regulator p21/WAF/CDKN1A and disrupts TGF-β-driven differentiation of smooth muscle cells. Identification of YY1AP1 mutations as a cause of FMD indicates that this condition can result from underlying genetic variants that significantly alter the phenotype of vascular smooth muscle cells.

}, keywords = {Adolescent, Adult, Bone and Bones, Brachydactyly, Cell Cycle Checkpoints, Exome, Female, Fibromuscular Dysplasia, Genes, Recessive, Heterozygote, Homozygote, Humans, Learning Disorders, Male, Middle Aged, Muscle, Smooth, Vascular, Mutation, Nuclear Proteins, Pedigree, Syndactyly, Syndrome, Transcription Factors}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2016.11.008}, author = {Guo, Dong-Chuan and Duan, Xue-Yan and Regalado, Ellen S and Mellor-Crummey, Lauren and Kwartler, Callie S and Kim, Dong and Lieberman, Kenneth and de Vries, Bert B A and Pfundt, Rolph and Schinzel, Albert and Kotzot, Dieter and Shen, Xuetong and Yang, Min-Lee and Bamshad, Michael J and Nickerson, Deborah A and Gornik, Heather L and Ganesh, Santhi K and Braverman, Alan C and Grange, Dorothy K and Milewicz, Dianna M} } @article {393, title = {Loss-of-Function Variants in MYLK Cause Recessive Megacystis Microcolon Intestinal Hypoperistalsis Syndrome.}, journal = {Am J Hum Genet}, volume = {101}, year = {2017}, month = {2017 Jul 06}, pages = {123-129}, abstract = {

Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is a congenital disorder characterized by loss of smooth muscle contraction in the bladder and intestine. To date, three genes are known to be involved in MMIHS pathogenesis: ACTG2, MYH11, and LMOD1. However, for approximately 10\% of affected individuals, the genetic cause of the disease is unknown, suggesting that~other~loci are most likely involved. Here, we report on three MMIHS-affected subjects from two consanguineous families with~no~variants~in the known MMIHS-associated genes. By performing homozygosity mapping and whole-exome sequencing, we found~homozygous variants in myosin light chain kinase (MYLK) in both families. We identified a 7~bp duplication (c.3838_3844dupGAAAGCG~[p.Glu1282_Glyfs51]) in one family and a putative splice-site variant (c.3985+5C>A) in the other. Expression studies and splicing assays indicated that both variants affect normal MYLK expression. Because MYLK encodes an important kinase required for myosin activation and subsequent interaction with actin filaments, it is likely that in its absence, contraction of smooth muscle cells is impaired. The existence of a conditional-Mylk-knockout mouse model with severe gut dysmotility and abnormal function of the bladder supports the involvement of this gene in MMIHS pathogenesis. In aggregate, our findings implicate MYLK as a gene involved in the recessive form of MMIHS, confirming that this disease of the visceral organs is heterogeneous with a myopathic origin.

}, keywords = {Abnormalities, Multiple, Base Sequence, Colon, Female, Genes, Recessive, Homozygote, Humans, Intestinal Pseudo-Obstruction, Male, Mutation, Myosin-Light-Chain Kinase, Pedigree, Urinary Bladder}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2017.05.011}, author = {Halim, Danny and Brosens, Erwin and Muller, Fran{\c c}oise and Wangler, Michael F and Beaudet, Arthur L and Lupski, James R and Akdemir, Zeynep H Coban and Doukas, Michael and Stoop, Hans J and de Graaf, Bianca M and Brouwer, Rutger W W and van Ijcken, Wilfred F J and Oury, Jean-Fran{\c c}ois and Rosenblatt, Jonathan and Burns, Alan J and Tibboel, Dick and Hofstra, Robert M W and Alves, Maria M} } @article {389, title = {MED resulting from recessively inherited mutations in the gene encoding calcium-activated nucleotidase CANT1.}, journal = {Am J Med Genet A}, volume = {173}, year = {2017}, month = {2017 Sep}, pages = {2415-2421}, abstract = {

Multiple Epiphyseal Dysplasia (MED) is a relatively mild skeletal dysplasia characterized by mild short stature, joint pain, and early-onset osteoarthropathy. Dominantly inherited mutations in COMP, MATN3, COL9A1, COL9A2, and COL9A3, and recessively inherited mutations in SLC26A2, account for the molecular basis of disease in about 80-85\% of the cases. In two families with recurrent MED of an unknown molecular basis, we used exome sequencing and candidate gene analysis to identify homozygosity for recessively inherited missense mutations in CANT1, which encodes calcium-activated nucleotidase 1. The MED phenotype is thus allelic to the more severe Desbuquois dysplasia phenotype and the results identify CANT1 as a second locus for recessively inherited MED.

}, keywords = {Adult, Base Sequence, Child, Child, Preschool, Exome, Female, Genes, Recessive, Humans, Male, Mutation, Missense, Nucleotidases, Osteochondrodysplasias, Pedigree, Radiography}, issn = {1552-4833}, doi = {10.1002/ajmg.a.38349}, author = {Balasubramanian, Karthika and Li, Bing and Krakow, Deborah and Nevarez, Lisette and Ho, Patric J and Ainsworth, Julia A and Nickerson, Deborah A and Bamshad, Michael J and Immken, LaDonna and Lachman, Ralph S and Cohn, Daniel H} } @article {395, title = {Mutations in KDSR Cause Recessive Progressive Symmetric Erythrokeratoderma.}, journal = {Am J Hum Genet}, volume = {100}, year = {2017}, month = {2017 Jun 01}, pages = {978-984}, abstract = {

The discovery of new genetic determinants of inherited skin disorders has been instrumental to the understanding of epidermal function, differentiation, and renewal. Here, we show that mutations in KDSR (3-ketodihydrosphingosine reductase), encoding an enzyme in the ceramide synthesis pathway, lead to a previously undescribed recessive Mendelian disorder in the progressive symmetric erythrokeratoderma spectrum. This disorder is characterized by severe lesions of thick scaly skin on the face and genitals and thickened, red, and scaly skin on the hands and feet. Although exome sequencing revealed several of the KDSR mutations, we employed genome sequencing to discover a pathogenic 346 kb inversion in multiple probands, and cDNA sequencing and a splicing assay established that two mutations, including a recurrent silent third base change, cause exon skipping. Immunohistochemistry and yeast complementation studies demonstrated that the mutations cause defects in KDSR function. Systemic isotretinoin therapy has achieved nearly complete resolution in the two probands in whom it has been applied, consistent with the effects of retinoic acid on alternative pathways for ceramide generation.

}, keywords = {Alcohol Oxidoreductases, Ceramides, Genes, Recessive, Genetic Complementation Test, Genetic Predisposition to Disease, Heterozygote, Humans, Intermediate Filament Proteins, Keratosis, Mutation, Polymorphism, Single Nucleotide, RNA Splicing, Saccharomyces cerevisiae}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2017.05.003}, author = {Boyden, Lynn M and Vincent, Nicholas G and Zhou, Jing and Hu, Ronghua and Craiglow, Brittany G and Bayliss, Susan J and Rosman, Ilana S and Lucky, Anne W and Diaz, Luis A and Goldsmith, Lowell A and Paller, Amy S and Lifton, Richard P and Baserga, Susan J and Choate, Keith A} } @article {355, title = {PRUNE is crucial for normal brain development and mutated in microcephaly with neurodevelopmental impairment.}, journal = {Brain}, volume = {140}, year = {2017}, month = {2017 Apr 01}, pages = {940-952}, abstract = {

PRUNE is a member of the DHH (Asp-His-His) phosphoesterase protein superfamily of molecules important for cell motility, and implicated in cancer progression. Here we investigated multiple families from Oman, India, Iran and Italy with individuals affected by a new autosomal recessive neurodevelopmental and degenerative disorder in which the cardinal features include primary microcephaly and profound global developmental delay. Our genetic studies identified biallelic mutations of PRUNE1 as responsible. Our functional assays of disease-associated variant alleles revealed impaired microtubule polymerization, as well as cell migration and proliferation properties, of mutant PRUNE. Additionally, our studies also highlight a potential new role for PRUNE during microtubule polymerization, which is essential for the cytoskeletal rearrangements that occur during cellular division and proliferation. Together these studies define PRUNE as a molecule fundamental for normal human cortical development and define cellular and clinical consequences associated with PRUNE mutation.

}, keywords = {Adolescent, Brain, Carrier Proteins, Cell Differentiation, Cell Movement, Cerebral Cortex, Child, Child, Preschool, Cytoskeleton, Developmental Disabilities, Female, Genes, Recessive, Heredodegenerative Disorders, Nervous System, Humans, Infant, Male, Microcephaly, Microtubules, Mutation, Pedigree, Young Adult}, issn = {1460-2156}, doi = {10.1093/brain/awx014}, author = {Zollo, Massimo and Ahmed, Mustafa and Ferrucci, Veronica and Salpietro, Vincenzo and Asadzadeh, Fatemeh and Carotenuto, Marianeve and Maroofian, Reza and Al-Amri, Ahmed and Singh, Royana and Scognamiglio, Iolanda and Mojarrad, Majid and Musella, Luca and Duilio, Angela and Di Somma, Angela and Karaca, Ender and Rajab, Anna and Al-Khayat, Aisha and Mohan Mohapatra, Tribhuvan and Eslahi, Atieh and Ashrafzadeh, Farah and Rawlins, Lettie E and Prasad, Rajniti and Gupta, Rashmi and Kumari, Preeti and Srivastava, Mona and Cozzolino, Flora and Kumar Rai, Sunil and Monti, Maria and Harlalka, Gaurav V and Simpson, Michael A and Rich, Philip and Al-Salmi, Fatema and Patton, Michael A and Chioza, Barry A and Efthymiou, Stephanie and Granata, Francesca and Di Rosa, Gabriella and Wiethoff, Sarah and Borgione, Eugenia and Scuderi, Carmela and Mankad, Kshitij and Hanna, Michael G and Pucci, Piero and Houlden, Henry and Lupski, James R and Crosby, Andrew H and Baple, Emma L} } @article {89, title = {Autosomal-Recessive Hearing Impairment Due to Rare Missense Variants within S1PR2.}, journal = {Am J Hum Genet}, volume = {98}, year = {2016}, month = {2016 Feb 04}, pages = {331-8}, abstract = {

The sphingosine-1-phosphate receptors (S1PRs) are a well-studied class of transmembrane G protein-coupled sphingolipid receptors that mediate multiple cellular processes. However, S1PRs have not been previously reported to be involved in the genetic etiology of human traits. S1PR2 lies within the autosomal-recessive nonsyndromic hearing impairment (ARNSHI) locus DFNB68 on 19p13.2. From exome sequence data we identified two pathogenic S1PR2 variants, c.323G>C (p.Arg108Pro) and c.419A>G (p.Tyr140Cys). Each of these variants co-segregates with congenital profound hearing impairment in consanguineous Pakistani families with maximum LOD scores of 6.4 for family DEM4154 and 3.3 for family PKDF1400. Neither S1PR2 missense variant was reported among \~{}120,000 chromosomes in the Exome Aggregation Consortium database, in 76 unrelated Pakistani exomes, or in 720 Pakistani control chromosomes. Both DNA variants affect highly conserved residues of S1PR2 and are predicted to be damaging by multiple bioinformatics tools. Molecular modeling predicts that these variants affect binding of sphingosine-1-phosphate (p.Arg108Pro) and G protein docking (p.Tyr140Cys). In the previously reported S1pr2(-/-) mice, stria vascularis abnormalities, organ of Corti degeneration, and profound hearing loss were~observed. Additionally, hair cell defects were seen in both knockout mice and morphant zebrafish. Family PKDF1400 presents with ARNSHI, which is consistent with the lack of gross malformations in S1pr2(-/-) mice, whereas family DEM4154 has lower limb malformations in addition to hearing loss. Our findings suggest the possibility of developing therapies against hair cell damage (e.g., from ototoxic drugs) through targeted stimulation of S1PR2.

}, keywords = {Amino Acid Sequence, Asian Continental Ancestry Group, Chromosomes, Human, Pair 19, Exome, Genes, Recessive, Hearing Loss, Humans, Lod Score, Logistic Models, Lysophospholipids, Models, Molecular, Molecular Sequence Data, Mutation, Missense, Pedigree, Phenotype, Receptors, Lysosphingolipid, Sphingosine}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2015.12.004}, author = {Santos-Cortez, Regie Lyn P and Faridi, Rabia and Rehman, Atteeq U and Lee, Kwanghyuk and Ansar, Muhammad and Wang, Xin and Morell, Robert J and Isaacson, Rivka and Belyantseva, Inna A and Dai, Hang and Acharya, Anushree and Qaiser, Tanveer A and Muhammad, Dost and Ali, Rana Amjad and Shams, Sulaiman and Hassan, Muhammad Jawad and Shahzad, Shaheen and Raza, Syed Irfan and Bashir, Zil-E-Huma and Smith, Joshua D and Nickerson, Deborah A and Bamshad, Michael J and Riazuddin, Sheikh and Ahmad, Wasim and Friedman, Thomas B and Leal, Suzanne M} } @article {37, title = {Biallelic Mutations in Citron Kinase Link Mitotic Cytokinesis to Human Primary Microcephaly.}, journal = {Am J Hum Genet}, volume = {99}, year = {2016}, month = {2016 Aug 04}, pages = {501-10}, abstract = {

Cell division terminates with cytokinesis and cellular separation. Autosomal-recessive primary microcephaly (MCPH) is a neurodevelopmental disorder characterized by a reduction in brain and head size at birth in addition to non-progressive intellectual disability. MCPH is genetically heterogeneous, and 16 loci are known to be associated with loss-of-function mutations predominantly affecting centrosomal-associated proteins, but the multiple roles of centrosomes in cellular function has left questions about etiology. Here, we identified three families affected by homozygous missense mutations in CIT, encoding citron rho-interacting kinase (CIT), which has established roles in cytokinesis. All mutations caused substitution of conserved amino acid residues in the kinase domain and impaired kinase activity. Neural progenitors that were differentiated from induced pluripotent stem cells (iPSCs) derived from individuals with these mutations exhibited abnormal cytokinesis with delayed mitosis, multipolar spindles, and increased apoptosis, rescued by CRISPR/Cas9 genome editing. Our results highlight the importance of cytokinesis in the pathology of primary microcephaly.

}, keywords = {Alleles, Apoptosis, Centrosome, Child, Child, Preschool, Cytokinesis, Female, Genes, Recessive, Humans, Infant, Newborn, Intracellular Signaling Peptides and Proteins, Male, Microcephaly, Mitosis, Mutation, Missense, Pedigree, Protein Serine-Threonine Kinases}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2016.07.004}, author = {Li, Hongda and Bielas, Stephanie L and Zaki, Maha S and Ismail, Samira and Farfara, Dorit and Um, Kyongmi and Rosti, Rasim O and Scott, Eric C and Tu, Shu and Chi, Neil C and Gabriel, Stacey and Erson-Omay, Emine Z and Ercan-Sencicek, A Gulhan and Yasuno, Katsuhito and {\c C}a{\u g}layan, Ahmet Okay and Kaymak{\c c}alan, Hande and Ekici, Bar{\i}{\c s} and Bilguvar, Kaya and G{\"u}nel, Murat and Gleeson, Joseph G} } @article {40, title = {Characterization of Greater Middle Eastern genetic variation for enhanced disease gene discovery.}, journal = {Nat Genet}, volume = {48}, year = {2016}, month = {2016 09}, pages = {1071-6}, abstract = {

The Greater Middle East (GME) has been a central hub of human migration and population admixture. The tradition of consanguinity, variably practiced in the Persian Gulf region, North Africa, and Central Asia, has resulted in an elevated burden of recessive disease. Here we generated a whole-exome GME variome from 1,111 unrelated subjects. We detected substantial diversity and admixture in continental and subregional populations, corresponding to several ancient founder populations with little evidence of bottlenecks. Measured consanguinity rates were an order of magnitude above those in other sampled populations, and the GME population exhibited an increased burden of runs of homozygosity (ROHs) but showed no evidence for reduced burden of deleterious variation due to classically theorized {\textquoteright}genetic purging{\textquoteright}. Applying this database to unsolved recessive conditions in the GME population reduced the number of potential disease-causing variants by four- to sevenfold. These results show variegated genetic architecture in GME populations and support future human genetic discoveries in Mendelian and population genetics.

}, keywords = {Asian Continental Ancestry Group, Cohort Studies, Consanguinity, Disease, European Continental Ancestry Group, Exome, Genes, Recessive, Genetic Markers, Genetic Variation, Genetics, Population, Genome, Human, Genome-Wide Association Study, Homozygote, Human Migration, Humans, Middle East}, issn = {1546-1718}, doi = {10.1038/ng.3592}, author = {Scott, Eric M and Halees, Anason and Itan, Yuval and Spencer, Emily G and He, Yupeng and Azab, Mostafa Abdellateef and Gabriel, Stacey B and Belkadi, Aziz and Boisson, Bertrand and Abel, Laurent and Clark, Andrew G and Alkuraya, Fowzan S and Casanova, Jean-Laurent and Gleeson, Joseph G} } @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 {32, title = {Exome Sequencing Identifies Biallelic MSH3 Germline Mutations as a Recessive Subtype of Colorectal Adenomatous Polyposis.}, journal = {Am J Hum Genet}, volume = {99}, year = {2016}, month = {2016 Aug 04}, pages = {337-51}, abstract = {

In \~{}30\% of families affected by colorectal adenomatous polyposis, no germline mutations have been identified in the previously implicated genes APC, MUTYH, POLE, POLD1, and NTHL1, although a hereditary etiology is likely. To uncover further genes with high-penetrance causative mutations, we performed exome sequencing of leukocyte DNA from 102 unrelated individuals with unexplained adenomatous polyposis. We identified two unrelated individuals with differing compound-heterozygous loss-of-function (LoF) germline mutations in the mismatch-repair gene MSH3. The impact of the MSH3 mutations (c.1148delA, c.2319-1G>A, c.2760delC, and c.3001-2A>C) was indicated at the RNA and protein levels. Analysis of the diseased individuals{\textquoteright} tumor tissue demonstrated high microsatellite instability of di- and tetranucleotides (EMAST), and immunohistochemical staining illustrated a complete loss of nuclear MSH3 in normal and tumor tissue, confirming the LoF effect and causal relevance of the mutations. The pedigrees, genotypes, and frequency of MSH3 mutations in the general population are consistent with an autosomal-recessive mode of inheritance. Both index persons have an affected sibling carrying the same mutations. The tumor spectrum in these four persons comprised colorectal and duodenal adenomas, colorectal cancer, gastric cancer, and an early-onset astrocytoma. Additionally, we detected one unrelated individual with biallelic PMS2 germline mutations, representing constitutional mismatch-repair deficiency. Potentially causative variants in 14 more candidate genes identified in 26 other individuals require further workup. In the present study, we identified biallelic germline MSH3 mutations in individuals with a suspected hereditary tumor syndrome. Our data suggest that MSH3 mutations represent an additional recessive subtype of colorectal adenomatous polyposis.

}, keywords = {Adenomatous Polyposis Coli, Adolescent, Adult, Alleles, Child, Preschool, Colorectal Neoplasms, DNA Mutational Analysis, DNA-Binding Proteins, Exome, Female, Genes, Recessive, Germ-Line Mutation, Humans, Male, Middle Aged, Mismatch Repair Endonuclease PMS2, MutS Homolog 3 Protein, Pedigree}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2016.06.015}, author = {Adam, Ronja and Spier, Isabel and Zhao, Bixiao and Kloth, Michael and Marquez, Jonathan and Hinrichsen, Inga and Kirfel, Jutta and Tafazzoli, Aylar and Horpaopan, Sukanya and Uhlhaas, Siegfried and Stienen, Dietlinde and Friedrichs, Nicolaus and Altm{\"u}ller, Janine and Laner, Andreas and Holzapfel, Stefanie and Peters, Sophia and Kayser, Katrin and Thiele, Holger and Holinski-Feder, Elke and Marra, Giancarlo and Kristiansen, Glen and N{\"o}then, Markus M and B{\"u}ttner, Reinhard and M{\"o}slein, Gabriela and Betz, Regina C and Brieger, Angela and Lifton, Richard P and Aretz, Stefan} } @article {10, title = {MIPEP recessive variants cause a syndrome of left ventricular non-compaction, hypotonia, and infantile death.}, journal = {Genome Med}, volume = {8}, year = {2016}, month = {2016 Nov 01}, pages = {106}, abstract = {

BACKGROUND: Mitochondrial presequence proteases perform fundamental functions as they process about 70~\% of all mitochondrial preproteins that are encoded in the nucleus and imported posttranslationally. The mitochondrial intermediate presequence protease MIP/Oct1, which carries out precursor processing, has not yet been established to have a role in human disease.

METHODS: Whole exome sequencing was performed on four unrelated probands with left ventricular non-compaction (LVNC), developmental delay (DD), seizures, and severe hypotonia. Proposed pathogenic variants were confirmed by Sanger sequencing or array comparative genomic hybridization. Functional analysis of the identified MIP variants was performed using the model organism Saccharomyces cerevisiae as the protein and its functions are highly conserved from yeast to human.

RESULTS: Biallelic single nucleotide variants (SNVs) or copy number variants (CNVs) in MIPEP, which encodes MIP, were present in all four probands, three of whom had infantile/childhood death. Two patients had compound heterozygous SNVs (p.L582R/p.L71Q and p.E602*/p.L306F) and one patient from a consanguineous family had a homozygous SNV (p.K343E). The fourth patient, identified through the GeneMatcher tool, a part of the Matchmaker Exchange Project, was found to have inherited a paternal SNV (p.H512D) and a maternal CNV (1.4-Mb deletion of 13q12.12) that includes MIPEP. All amino acids affected in the patients{\textquoteright} missense variants are highly conserved from yeast to human and therefore S. cerevisiae was employed for functional analysis (for p.L71Q, p.L306F, and p.K343E). The mutations p.L339F (human p.L306F) and p.K376E (human p.K343E) resulted in a severe decrease of Oct1 protease activity and accumulation of non-processed Oct1 substrates and consequently impaired viability under respiratory growth conditions. The p.L83Q (human p.L71Q) failed to localize to the mitochondria.

CONCLUSIONS: Our findings reveal for the first time the role of the mitochondrial intermediate peptidase in human disease. Loss of MIP function results in a syndrome which consists of LVNC, DD, seizures, hypotonia, and cataracts. Our approach highlights the power of data exchange and the importance of an interrelationship between clinical and research efforts for disease gene discovery.

}, keywords = {Adult, Amino Acid Sequence, Female, Genes, Recessive, Heart Defects, Congenital, Humans, Infant, Infant, Newborn, Male, Metalloendopeptidases, Muscle Hypotonia, Pedigree, Phenotype, Sequence Homology, Amino Acid, Sudden Infant Death, Syndrome}, issn = {1756-994X}, doi = {10.1186/s13073-016-0360-6}, author = {Eldomery, Mohammad K and Akdemir, Zeynep C and V{\"o}gtle, F-Nora and Charng, Wu-Lin and Mulica, Patrycja and Rosenfeld, Jill A and Gambin, Tomasz and Gu, Shen and Burrage, Lindsay C and Al Shamsi, Aisha and Penney, Samantha and Jhangiani, Shalini N and Zimmerman, Holly H and Muzny, Donna M and Wang, Xia and Tang, Jia and Medikonda, Ravi and Ramachandran, Prasanna V and Wong, Lee-Jun and Boerwinkle, Eric and Gibbs, Richard A and Eng, Christine M and Lalani, Seema R and Hertecant, Jozef and Rodenburg, Richard J and Abdul-Rahman, Omar A and Yang, Yaping and Xia, Fan and Wang, Meng C and Lupski, James R and Meisinger, Chris and Sutton, V Reid} } @article {84, title = {Mutations in nuclear pore genes NUP93, NUP205 and XPO5 cause steroid-resistant nephrotic syndrome.}, journal = {Nat Genet}, volume = {48}, year = {2016}, month = {2016 Apr}, pages = {457-65}, abstract = {

Nucleoporins are essential components of the nuclear pore complex (NPC). Only a few diseases have been attributed to NPC dysfunction. Steroid-resistant nephrotic syndrome (SRNS), a frequent cause of chronic kidney disease, is caused by dysfunction of glomerular podocytes. Here we identify in eight families with SRNS mutations in NUP93, its interaction partner NUP205 or XPO5 (encoding exportin 5) as hitherto unrecognized monogenic causes of SRNS. NUP93 mutations caused disrupted NPC assembly. NUP93 knockdown reduced the presence of NUP205 in the NPC, and, reciprocally, a NUP205 alteration abrogated NUP93 interaction. We demonstrate that NUP93 and exportin 5 interact with the signaling protein SMAD4 and that NUP93 mutations abrogated interaction with SMAD4. Notably, NUP93 mutations interfered with BMP7-induced SMAD transcriptional reporter activity. We hereby demonstrate that mutations of NUP genes cause a distinct renal disease and identify aberrant SMAD signaling as a new disease mechanism of SRNS, opening a potential new avenue for treatment.

}, keywords = {Age of Onset, Amino Acid Sequence, Animals, Cell Movement, Cell Proliferation, Cells, Cultured, Child, Child, Preschool, Drug Resistance, Female, Genes, Recessive, Genetic Association Studies, Genetic Linkage, HEK293 Cells, Humans, Infant, Karyopherins, Male, Mice, Molecular Sequence Data, Mutation, Nephrotic Syndrome, Nuclear Pore Complex Proteins, Oxidative Stress, Podocytes, Sequence Analysis, DNA, Steroids, Xenopus laevis}, issn = {1546-1718}, doi = {10.1038/ng.3512}, author = {Braun, Daniela A and Sadowski, Carolin E and Kohl, Stefan and Lovric, Svjetlana and Astrinidis, Susanne A and Pabst, Werner L and Gee, Heon Yung and Ashraf, Shazia and Lawson, Jennifer A and Shril, Shirlee and Airik, Merlin and Tan, Weizhen and Schapiro, David and Rao, Jia and Choi, Won-Il and Hermle, Tobias and Kemper, Markus J and Pohl, Martin and Ozaltin, Fatih and Konrad, Martin and Bogdanovic, Radovan and B{\"u}scher, Rainer and Helmchen, Udo and Serdaroglu, Erkin and Lifton, Richard P and Antonin, Wolfram and Hildebrandt, Friedhelm} } @article {101, title = {A novel missense variant in the PNPLA1 gene underlies congenital ichthyosis in three consanguineous families.}, journal = {J Eur Acad Dermatol Venereol}, volume = {30}, year = {2016}, month = {2016 Dec}, pages = {e210-e213}, keywords = {Amino Acid Sequence, Consanguinity, Female, Genes, Recessive, Humans, Ichthyosiform Erythroderma, Congenital, Lipase, Male, Mutation, Missense, Pakistan, Pedigree, Sequence Homology, Amino Acid}, issn = {1468-3083}, doi = {10.1111/jdv.13540}, author = {Ahmad, F and Ansar, M and Mehmood, S and Izoduwa, A and Lee, K and Nasir, A and Abrar, M and Mehmood, S and Ullah, A and Aziz, A and Smith, J D and Shendure, J and Bamshad, M J and Nicekrson, D A and Santos-Cortez, R L P and Leal, S M and Ahmad, W} } @article {85, title = {Recurrent recessive mutation in deoxyguanosine kinase causes idiopathic noncirrhotic portal hypertension.}, journal = {Hepatology}, volume = {63}, year = {2016}, month = {2016 06}, pages = {1977-86}, abstract = {

UNLABELLED: Despite advances in the diagnosis and management of idiopathic noncirrhotic portal hypertension, its pathogenesis remains elusive. Insight may be gained from study of early-onset familial idiopathic noncirrhotic portal hypertension, in which Mendelian mutations may account for disease. We performed exome sequencing of eight subjects from six kindreds with onset of portal hypertension of indeterminate etiology during infancy or childhood. Three subjects from two consanguineous families shared the identical rare homozygous p.N46S mutation in DGUOK, a deoxyguanosine kinase required for mitochondrial DNA replication; haplotype sharing demonstrated that the mutation in the two families was inherited from a remote common ancestor. All three affected subjects had stable portal hypertension with noncirrhotic liver disease for 6-16 years of follow-up. This mutation impairs adenosine triphosphate binding and reduces catalytic activity. Loss-of-function mutations in DGUOK have previously been implicated in cirrhosis and liver failure but not in isolated portal hypertension. Interestingly, treatment of patients with human immunodeficiency viral infection with the nucleoside analogue didanosine is known to cause portal hypertension in a subset of patients and lowers deoxyguanosine kinase levels in vitro; the current findings implicate these effects on deoxyguanosine kinase in the causal mechanism.

CONCLUSION: Our findings provide new insight into the mechanisms mediating inherited and acquired noncirrhotic portal hypertension, expand the phenotypic spectrum of DGUOK deficiency, and provide a new genetic test for a specific cause of idiopathic noncirrhotic portal hypertension. (Hepatology 2016;63:1977-1986).

}, keywords = {Adolescent, Amino Acid Sequence, Animals, Cattle, Child, Child, Preschool, DNA Mutational Analysis, Dogs, Female, Genes, Recessive, Homozygote, Humans, Hypertension, Portal, Infant, Liver Failure, Male, Molecular Sequence Data, Pedigree, Phosphotransferases (Alcohol Group Acceptor), Principal Component Analysis, Rats, Young Adult}, issn = {1527-3350}, doi = {10.1002/hep.28499}, author = {Vilarinho, S{\'\i}lvia and Sari, Sinan and Yilmaz, G{\"u}ldal and Stiegler, Amy L and Boggon, Titus J and Jain, Dhanpat and Akyol, G{\"u}len and Dalgi{\c c}, Buket and G{\"u}nel, Murat and Lifton, Richard P} } @article {204, title = {Challenges and solutions for gene identification in the presence of familial locus heterogeneity.}, journal = {Eur J Hum Genet}, volume = {23}, year = {2015}, month = {2015 Sep}, pages = {1207-15}, abstract = {

Next-generation sequencing (NGS) of exomes and genomes has accelerated the identification of genes involved in Mendelian phenotypes. However, many NGS studies fall short of identifying causal variants, with estimates for success rates as low as 25\% for uncovering the pathological variant underlying disease etiology. An important reason for such failures is familial locus heterogeneity, where within a single pedigree causal variants in two or more genes underlie Mendelian trait etiology. As examples of intra- and inter-sibship familial locus heterogeneity, we present 10 consanguineous Pakistani families segregating hearing impairment due to homozygous variants in two different hearing impairment genes and a European-American pedigree in which hearing impairment is caused by four variants in three different genes. We have identified 41 additional pedigrees with syndromic and nonsyndromic hearing impairment for which a single previously reported hearing impairment gene has been identified but only segregates with the phenotype in a subset of affected pedigree members. We estimate that locus heterogeneity occurs in 15.3\% (95\% confidence interval: 11.9\%, 19.9\%) of the families in our collection. We demonstrate novel approaches to apply linkage analysis and homozygosity mapping (for autosomal recessive consanguineous pedigrees), which can be used to detect locus heterogeneity using either NGS or SNP array data. Results from linkage analysis and homozygosity mapping can also be used to group sibships or individuals most likely to be segregating the same causal variants and thereby increase the success rate of gene identification.

}, keywords = {Asian Continental Ancestry Group, Calcium-Binding Proteins, Chromosome Mapping, Connexin 26, Connexins, Consanguinity, European Continental Ancestry Group, Female, Genes, Recessive, Genetic Heterogeneity, Genetic Linkage, Genetic Loci, Genetic Predisposition to Disease, Genome, Human, Genotype, Hearing Loss, Hepatocyte Growth Factor, High-Throughput Nucleotide Sequencing, Homozygote, Humans, Male, Membrane Transport Proteins, Mutation, Pedigree, Phenotype, Sulfate Transporters}, issn = {1476-5438}, doi = {10.1038/ejhg.2014.266}, author = {Rehman, Atteeq U and Santos-Cortez, Regie Lyn P and Drummond, Meghan C and Shahzad, Mohsin and Lee, Kwanghyuk and Morell, Robert J and Ansar, Muhammad and Jan, Abid and Wang, Xin and Aziz, Abdul and Riazuddin, Saima and Smith, Joshua D and Wang, Gao T and Ahmed, Zubair M and Gul, Khitab and Shearer, A Eliot and Smith, Richard J H and Shendure, Jay and Bamshad, Michael J and Nickerson, Deborah A and Hinnant, John and Khan, Shaheen N and Fisher, Rachel A and Ahmad, Wasim and Friderici, Karen H and Riazuddin, Sheikh and Friedman, Thomas B and Wilch, Ellen S and Leal, Suzanne M} } @article {109, title = {Mutations in Either TUBB or MAPRE2 Cause Circumferential Skin Creases Kunze Type.}, journal = {Am J Hum Genet}, volume = {97}, year = {2015}, month = {2015 Dec 03}, pages = {790-800}, abstract = {

Circumferential skin creases Kunze type (CSC-KT) is a specific congenital entity with an unknown genetic cause. The disease phenotype comprises characteristic circumferential skin creases accompanied by intellectual disability, a cleft palate, short stature, and dysmorphic features. Here, we report that mutations in either MAPRE2 or TUBB underlie the genetic origin of this syndrome. MAPRE2 encodes a member of the microtubule end-binding family of proteins that bind to the guanosine triphosphate cap at growing microtubule plus ends, and TUBB encodes a β-tubulin isotype that is expressed abundantly in the developing brain. Functional analyses of the TUBB mutants show multiple defects in the chaperone-dependent tubulin heterodimer folding and assembly pathway that leads to a compromised yield of native heterodimers. The TUBB mutations also have an impact on microtubule dynamics. For MAPRE2, we show that the mutations result in enhanced MAPRE2 binding to microtubules, implying an increased dwell time at microtubule plus ends. Further, in vivo analysis of MAPRE2 mutations in a zebrafish model of craniofacial development shows that the variants most likely perturb the patterning of branchial arches, either through excessive activity (under a recessive paradigm) or through haploinsufficiency (dominant de novo paradigm). Taken together, our data add CSC-KT to the growing list of tubulinopathies and highlight how multiple inheritance paradigms can affect dosage-sensitive biological systems so as to result in the same clinical defect.

}, keywords = {Adolescent, Animals, Brain, Child, Cutis Laxa, Female, Gene Dosage, Gene Expression Regulation, Developmental, Genes, Recessive, Hamartoma, Haploinsufficiency, Humans, Infant, Inheritance Patterns, Male, Microtubule-Associated Proteins, Microtubules, Mutation, Protein Folding, Protein Multimerization, Skin, Skin Abnormalities, Tubulin, Young Adult, Zebrafish}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2015.10.014}, author = {Isrie, Mala and Breuss, Martin and Tian, Guoling and Hansen, Andi Harley and Cristofoli, Francesca and Morandell, Jasmin and Kupchinsky, Zachari A and Sifrim, Alejandro and Rodriguez-Rodriguez, Celia Maria and Dapena, Elena Porta and Doonanco, Kurston and Leonard, Norma and Tinsa, Faten and Moortgat, St{\'e}phanie and Ulucan, Hakan and Koparir, Erkan and Karaca, Ender and Katsanis, Nicholas and Marton, Valeria and Vermeesch, Joris Robert and Davis, Erica E and Cowan, Nicholas J and Keays, David Anthony and Van Esch, Hilde} } @article {130, title = {Mutations in SPATA5 Are Associated with Microcephaly, Intellectual Disability, Seizures, and Hearing Loss.}, journal = {Am J Hum Genet}, volume = {97}, year = {2015}, month = {2015 Sep 03}, pages = {457-64}, abstract = {

Using whole-exome sequencing, we have identified in ten families 14 individuals with microcephaly, developmental delay, intellectual disability, hypotonia, spasticity, seizures, sensorineural hearing loss, cortical visual impairment, and rare autosomal-recessive predicted pathogenic variants in spermatogenesis-associated protein 5 (SPATA5). SPATA5 encodes a ubiquitously expressed member of the ATPase associated with diverse activities (AAA) protein family and is involved in mitochondrial morphogenesis during early spermatogenesis. It might also play a role in post-translational modification during cell differentiation in neuronal development. Mutations in SPATA5 might affect brain development and function, resulting in microcephaly, developmental delay, and intellectual disability.

}, keywords = {Abnormalities, Multiple, Amino Acid Sequence, ATPases Associated with Diverse Cellular Activities, Base Sequence, Exome, Female, Gene Frequency, Genes, Recessive, Hearing Loss, Homeodomain Proteins, Humans, Intellectual Disability, Male, Microcephaly, Molecular Sequence Data, Mutation, Seizures, Sequence Alignment, Sequence Analysis, DNA}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2015.07.014}, author = {Tanaka, Akemi J and Cho, Megan T and Millan, Francisca and Juusola, Jane and Retterer, Kyle and Joshi, Charuta and Niyazov, Dmitriy and Garnica, Adolfo and Gratz, Edward and Deardorff, Matthew and Wilkins, Alisha and Ortiz-Gonzalez, Xilma and Mathews, Katherine and Panzer, Karin and Brilstra, Eva and van Gassen, Koen L I and Volker-Touw, Catharina M L and van Binsbergen, Ellen and Sobreira, Nara and Hamosh, Ada and McKnight, Dianalee and Monaghan, Kristin G and Chung, Wendy K} } @article {205, title = {Biallelic truncating mutations in FMN2, encoding the actin-regulatory protein Formin 2, cause nonsyndromic autosomal-recessive intellectual disability.}, journal = {Am J Hum Genet}, volume = {95}, year = {2014}, month = {2014 Dec 04}, pages = {721-8}, abstract = {

Dendritic spines represent the major site of neuronal activity in the brain; they serve as the receiving point for neurotransmitters and undergo rapid activity-dependent morphological changes that correlate with learning and memory. Using a combination of homozygosity mapping and next-generation sequencing in two consanguineous families affected by nonsyndromic autosomal-recessive intellectual disability, we identified truncating mutations in formin 2 (FMN2), encoding a protein that belongs to the formin family of actin cytoskeleton nucleation factors and is highly expressed in the maturing brain. We found that FMN2 localizes to punctae along dendrites and that germline inactivation of mouse Fmn2 resulted in animals with decreased spine density; such mice were previously demonstrated to have a conditioned fear-learning defect. Furthermore, patient neural cells derived from induced pluripotent stem cells showed correlated decreased synaptic density. Thus, FMN2 mutations link intellectual disability either directly or indirectly to the regulation of actin-mediated synaptic spine density.

}, keywords = {Adolescent, Adult, Base Sequence, Chromosome Disorders, Cohort Studies, Consanguinity, Egypt, Exome, Female, Genes, Recessive, Genetic Linkage, High-Throughput Nucleotide Sequencing, Homozygote, Humans, Intellectual Disability, Male, Microfilament Proteins, Molecular Sequence Data, Nuclear Proteins, Pakistan, Pedigree, Sequence Analysis, DNA, Sequence Deletion}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2014.10.016}, author = {Law, Rosalind and Dixon-Salazar, Tracy and Jerber, Julie and Cai, Na and Abbasi, Ansar A and Zaki, Maha S and Mittal, Kirti and Gabriel, Stacey B and Rafiq, Muhammad Arshad and Khan, Valeed and Nguyen, Maria and Ali, Ghazanfar and Copeland, Brett and Scott, Eric and Vasli, Nasim and Mikhailov, Anna and Khan, Muhammad Nasim and Andrade, Danielle M and Ayaz, Muhammad and Ansar, Muhammad and Ayub, Muhammad and Vincent, John B and Gleeson, Joseph G} } @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 {236, title = {Individual exome analysis in diagnosis and management of paediatric liver failure of indeterminate aetiology.}, journal = {J Hepatol}, volume = {61}, year = {2014}, month = {2014 Nov}, pages = {1056-63}, abstract = {

BACKGROUND \& AIMS: In children with liver failure, as many as half remain of indeterminate aetiology. This hinders timely consideration of optimal treatment options. We posit that a significant subset of these children harbour known inherited metabolic liver diseases with atypical presentation or novel inborn errors of metabolism. We investigated the utility of whole-exome sequencing in three children with advanced liver disease of indeterminate aetiology.

METHODS: Patient 1 was a 10 year-old female diagnosed with Wilson disease but no detectable ATP7B mutations, and decompensated liver cirrhosis who underwent liver transplant and subsequently developed onset of neurodegenerative disease. Patient 2 was a full-term 2 day-old male with fatal acute liver failure of indeterminate aetiology. Patient 3 was an 8 year-old female with progressive syndromic cholestasis of unknown aetiology since age 3 months.

RESULTS: Unbiased whole-exome sequencing of germline DNA revealed homozygous mutations in MPV17 and SERAC1 as the disease causing genes in patient 1 and 2, respectively. This is the first demonstration of SERAC1 loss-of-function associated fatal acute liver failure. Patient 1 expands the phenotypic spectrum of the MPV17-related hepatocerebral mitochondrial DNA depletion syndrome. Patient 3 was found to have syndromic cholestasis due to bi-allelic NOTCH2 mutations.

CONCLUSIONS: Our findings validate the application of whole-exome sequencing in the diagnosis and management of children with advanced liver disease of indeterminate aetiology, with the potential to enhance optimal selection of treatment options and adequate counselling of families. Moreover, whole-exome sequencing revealed a hitherto unrecognized phenotypic spectrum of inherited metabolic liver diseases.

}, keywords = {Amino Acid Sequence, Base Sequence, Carboxylic Ester Hydrolases, Child, Cholestasis, DNA Mutational Analysis, End Stage Liver Disease, Exome, Fatal Outcome, Female, Genes, Recessive, Hepatolenticular Degeneration, Heterozygote, Homozygote, Humans, Infant, Newborn, Liver Failure, Liver Failure, Acute, Male, Membrane Proteins, Mitochondrial Proteins, Molecular Sequence Data, Pedigree, Receptor, Notch2, RNA Splice Sites, Sequence Homology, Amino Acid}, issn = {1600-0641}, doi = {10.1016/j.jhep.2014.06.038}, author = {Vilarinho, S{\'\i}lvia and Choi, Murim and Jain, Dhanpat and Malhotra, Ajay and Kulkarni, Sanjay and Pashankar, Dinesh and Phatak, Uma and Patel, Mohini and Bale, Allen and Mane, Shrikant and Lifton, Richard P and Mistry, Pramod K} } @article {274, title = {Mutations in TBC1D24, a gene associated with epilepsy, also cause nonsyndromic deafness DFNB86.}, journal = {Am J Hum Genet}, volume = {94}, year = {2014}, month = {2014 Jan 02}, pages = {144-52}, abstract = {

Inherited deafness is clinically and genetically heterogeneous. We recently mapped DFNB86, a locus associated with nonsyndromic deafness, to chromosome 16p. In this study, whole-exome sequencing was performed with genomic DNA from affected individuals from three large consanguineous families in which markers linked to DFNB86 segregate with profound deafness. Analyses of these data revealed homozygous mutation c.208G>T (p.Asp70Tyr) or c.878G>C (p.Arg293Pro) in TBC1D24 as the underlying cause of deafness in the three families. Sanger sequence analysis of TBC1D24 in an additional large family in which deafness segregates with DFNB86 identified the c.208G>T (p.Asp70Tyr) substitution. These mutations affect TBC1D24 amino acid residues that are conserved in orthologs ranging from fruit fly to human. Neither variant was observed in databases of single-nucleotide variants or in 634 chromosomes from ethnically matched control subjects. TBC1D24 in the mouse inner ear was immunolocalized predominantly to spiral ganglion neurons, indicating that DFNB86 deafness might be an auditory neuropathy spectrum disorder. Previously, six recessive mutations in TBC1D24 were reported to cause seizures (hearing loss was not reported) ranging in severity from epilepsy with otherwise normal development to epileptic encephalopathy resulting in childhood death. Two of our four families in which deafness segregates with mutant alleles of TBC1D24 were available for neurological examination. Cosegregation of epilepsy and deafness was not observed in these two families. Although the causal relationship between genotype and phenotype is not presently understood, our findings, combined with published data, indicate that recessive alleles of TBC1D24 can cause either epilepsy or nonsyndromic deafness.

}, keywords = {Alleles, Amino Acid Sequence, Carrier Proteins, Chromosomes, Human, Pair 16, Consanguinity, Deafness, Epilepsy, Exome, Exons, Female, Genes, Recessive, Genetic Loci, Genome-Wide Association Study, Heterozygote, Homozygote, Humans, Male, Molecular Sequence Data, Mutation, Pakistan, Pedigree, Phenotype, Polymorphism, Single Nucleotide, RNA, Messenger, Sequence Analysis, DNA}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2013.12.004}, author = {Rehman, Atteeq U and Santos-Cortez, Regie Lyn P and Morell, Robert J and Drummond, Meghan C and Ito, Taku and Lee, Kwanghyuk and Khan, Asma A and Basra, Muhammad Asim R and Wasif, Naveed and Ayub, Muhammad and Ali, Rana A and Raza, Syed I and Nickerson, Deborah A and Shendure, Jay and Bamshad, Michael and Riazuddin, Saima and Billington, Neil and Khan, Shaheen N and Friedman, Penelope L and Griffith, Andrew J and Ahmad, Wasim and Riazuddin, Sheikh and Leal, Suzanne M and Friedman, Thomas B} } @article {301, title = {Deletions of recessive disease genes: CNV contribution to carrier states and disease-causing alleles.}, journal = {Genome Res}, volume = {23}, year = {2013}, month = {2013 Sep}, pages = {1383-94}, abstract = {

Over 1200 recessive disease genes have been described in humans. The prevalence, allelic architecture, and per-genome load of pathogenic alleles in these genes remain to be fully elucidated, as does the contribution of DNA copy-number variants (CNVs) to carrier status and recessive disease. We mined CNV data from 21,470 individuals obtained by array-comparative genomic hybridization in a clinical diagnostic setting to identify deletions encompassing or disrupting recessive disease genes. We identified 3212 heterozygous potential carrier deletions affecting 419 unique recessive disease genes. Deletion frequency of these genes ranged from one occurrence to 1.5\%. When compared with recessive disease genes never deleted in our cohort, the 419 recessive disease genes affected by at least one carrier deletion were longer and located farther from known dominant disease genes, suggesting that the formation and/or prevalence of carrier CNVs may be affected by both local and adjacent genomic features and by selection. Some subjects had multiple carrier CNVs (307 subjects) and/or carrier deletions encompassing more than one recessive disease gene (206 deletions). Heterozygous deletions spanning multiple recessive disease genes may confer carrier status for multiple single-gene disorders, for complex syndromes resulting from the combination of two or more recessive conditions, or may potentially cause clinical phenotypes due to a multiply heterozygous state. In addition to carrier mutations, we identified homozygous and hemizygous deletions potentially causative for recessive disease. We provide further evidence that CNVs contribute to the allelic architecture of both carrier and recessive disease-causing mutations. Thus, a complete recessive carrier screening method or diagnostic test should detect CNV alleles.

}, keywords = {Alleles, Comparative Genomic Hybridization, Databases, Genetic, DNA Copy Number Variations, Gene Deletion, Gene Frequency, Genes, Dominant, Genes, Recessive, Genetic Diseases, Inborn, Homozygote, Humans}, issn = {1549-5469}, doi = {10.1101/gr.156075.113}, author = {Boone, Philip M and Campbell, Ian M and Baggett, Brett C and Soens, Zachry T and Rao, Mitchell M and Hixson, Patricia M and Patel, Ankita and Bi, Weimin and Cheung, Sau Wai and Lalani, Seema R and Beaudet, Arthur L and Stankiewicz, Pawel and Shaw, Chad A and Lupski, James R} } @article {308, title = {Perrault syndrome is caused by recessive mutations in CLPP, encoding a mitochondrial ATP-dependent chambered protease.}, journal = {Am J Hum Genet}, volume = {92}, year = {2013}, month = {2013 Apr 04}, pages = {605-13}, abstract = {

Perrault syndrome is a genetically and clinically heterogeneous autosomal-recessive condition characterized by sensorineural hearing loss and ovarian failure. By a combination of linkage analysis, homozygosity mapping, and exome sequencing in three families, we identified mutations in CLPP as the likely cause of this phenotype. In each family, affected individuals were homozygous for a different pathogenic CLPP allele: c.433A>C (p.Thr145Pro), c.440G>C (p.Cys147Ser), or an experimentally demonstrated splice-donor-site mutation, c.270+4A>G. CLPP, a component of a mitochondrial ATP-dependent proteolytic complex, is a highly conserved endopeptidase encoded by CLPP and forms an element of the evolutionarily ancient mitochondrial unfolded-protein response (UPR(mt)) stress signaling pathway. Crystal-structure modeling suggests that both substitutions would alter the structure of the CLPP barrel chamber that captures unfolded proteins and exposes them to proteolysis. Together with the previous identification of mutations in HARS2, encoding mitochondrial histidyl-tRNA synthetase, mutations in CLPP expose dysfunction of mitochondrial protein homeostasis as a cause of Perrault syndrome.

}, keywords = {Adenosine Triphosphate, Adolescent, Adult, ATP-Dependent Proteases, Endopeptidase Clp, Exome, Female, Genes, Recessive, Gonadal Dysgenesis, 46,XX, Hearing Loss, Sensorineural, Homozygote, Humans, In Situ Hybridization, Male, Mitochondria, Mutation, Pedigree, Phenotype, Young Adult}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2013.02.013}, author = {Jenkinson, Emma M and Rehman, Atteeq U and Walsh, Tom and Clayton-Smith, Jill and Lee, Kwanghyuk and Morell, Robert J and Drummond, Meghan C and Khan, Shaheen N and Naeem, Muhammad Asif and Rauf, Bushra and Billington, Neil and Schultz, Julie M and Urquhart, Jill E and Lee, Ming K and Berry, Andrew and Hanley, Neil A and Mehta, Sarju and Cilliers, Deirdre and Clayton, Peter E and Kingston, Helen and Smith, Miriam J and Warner, Thomas T and Black, Graeme C and Trump, Dorothy and Davis, Julian R E and Ahmad, Wasim and Leal, Suzanne M and Riazuddin, Sheikh and King, Mary-Claire and Friedman, Thomas B and Newman, William G} } @article {311, title = {Recessive loss of function of the neuronal ubiquitin hydrolase UCHL1 leads to early-onset progressive neurodegeneration.}, journal = {Proc Natl Acad Sci U S A}, volume = {110}, year = {2013}, month = {2013 Feb 26}, pages = {3489-94}, abstract = {

Ubiquitin C-terminal hydrolase-L1 (UCHL1), a neuron-specific de-ubiquitinating enzyme, is one of the most abundant proteins in the brain. We describe three siblings from a consanguineous union with a previously unreported early-onset progressive neurodegenerative syndrome featuring childhood onset blindness, cerebellar ataxia, nystagmus, dorsal column dysfuction, and spasticity with upper motor neuron dysfunction. Through homozygosity mapping of the affected individuals followed by whole-exome sequencing of the index case, we identified a previously undescribed homozygous missense mutation within the ubiquitin binding domain of UCHL1 (UCHL1(GLU7ALA)), shared by all affected subjects. As demonstrated by isothermal titration calorimetry, purified UCHL1(GLU7ALA), compared with WT, exhibited at least sevenfold reduced affinity for ubiquitin. In vitro, the mutation led to a near complete loss of UCHL1 hydrolase activity. The GLU7ALA variant is predicted to interfere with the substrate binding by restricting the proper positioning of the substrate for tunneling underneath the cross-over loop spanning the catalytic cleft of UCHL1. This interference with substrate binding, combined with near complete loss of hydrolase activity, resulted in a >100-fold reduction in the efficiency of UCHL1(GLU7ALA) relative to WT. These findings demonstrate a broad requirement of UCHL1 in the maintenance of the nervous system.

}, keywords = {Adult, Age of Onset, Amino Acid Sequence, Base Sequence, Child, Preschool, Exome, Female, Genes, Recessive, Homozygote, Humans, Hydrolysis, Male, Models, Molecular, Molecular Sequence Data, Mutation, Missense, Nerve Degeneration, Neurons, Pedigree, Protein Binding, Sequence Analysis, DNA, Substrate Specificity, Syndrome, Thermodynamics, Ubiquitin, Ubiquitin Thiolesterase}, issn = {1091-6490}, doi = {10.1073/pnas.1222732110}, author = {Bilguvar, Kaya and Tyagi, Navneet K and Ozkara, Cigdem and Tuysuz, Beyhan and Bakircioglu, Mehmet and Choi, Murim and Delil, Sakir and {\c C}a{\u g}layan, Ahmet O and Baranoski, Jacob F and Erturk, Ozdem and Yalcinkaya, Cengiz and Karacorlu, Murat and Dincer, Alp and Johnson, Michele H and Mane, Shrikant and Chandra, Sreeganga S and Louvi, Angeliki and Boggon, Titus J and Lifton, Richard P and Horwich, Arthur L and G{\"u}nel, Murat} } @article {306, title = {Recessive mutations in DGKE cause atypical hemolytic-uremic syndrome.}, journal = {Nat Genet}, volume = {45}, year = {2013}, month = {2013 May}, pages = {531-6}, abstract = {

Pathologic thrombosis is a major cause of mortality. Hemolytic-uremic syndrome (HUS) features episodes of small-vessel thrombosis resulting in microangiopathic hemolytic anemia, thrombocytopenia and renal failure. Atypical HUS (aHUS) can result from genetic or autoimmune factors that lead to pathologic complement cascade activation. Using exome sequencing, we identified recessive mutations in DGKE (encoding diacylglycerol kinase ɛ) that co-segregated with aHUS in nine unrelated kindreds, defining a distinctive Mendelian disease. Affected individuals present with aHUS before age 1 year, have persistent hypertension, hematuria and proteinuria (sometimes in the nephrotic range), and develop chronic kidney disease with age. DGKE is found in endothelium, platelets and podocytes. Arachidonic acid-containing diacylglycerols (DAG) activate protein kinase C (PKC), which promotes thrombosis, and DGKE normally inactivates DAG signaling. We infer that loss of DGKE function results in a prothrombotic state. These findings identify a new mechanism of pathologic thrombosis and kidney failure and have immediate implications for treating individuals with aHUS.

}, keywords = {Acute Kidney Injury, Atypical Hemolytic Uremic Syndrome, Child, Child, Preschool, Diacylglycerol Kinase, Exome, Female, Genes, Recessive, Hemolytic-Uremic Syndrome, Humans, Immunoenzyme Techniques, Infant, Male, Molecular Sequence Data, Mutation, Renal Insufficiency, Chronic, Thrombocytopenia, Thrombotic Microangiopathies}, issn = {1546-1718}, doi = {10.1038/ng.2590}, author = {Lemaire, Mathieu and Fremeaux-Bacchi, Veronique and Schaefer, Franz and Choi, Murim and Tang, Wai Ho and Le Quintrec, Moglie and Fakhouri, Fadi and Taque, Sophie and Nobili, Fran{\c c}ois and Martinez, Frank and Ji, Weizhen and Overton, John D and Mane, Shrikant M and N{\"u}rnberg, Gudrun and Altm{\"u}ller, Janine and Thiele, Holger and Morin, Denis and Deschenes, Georges and Baudouin, V{\'e}ronique and Llanas, Brigitte and Collard, Laure and Majid, Mohammed A and Simkova, Eva and N{\"u}rnberg, Peter and Rioux-Leclerc, Nathalie and Moeckel, Gilbert W and Gubler, Marie Claire and Hwa, John and Loirat, Chantal and Lifton, Richard P} }