@article {687, title = {Aberrant Function of the C-Terminal Tail of HIST1H1E Accelerates Cellular Senescence and Causes Premature Aging.}, journal = {Am J Hum Genet}, volume = {105}, year = {2019}, month = {2019 Sep 05}, pages = {493-508}, abstract = {

Histones mediate dynamic packaging of nuclear DNA in chromatin, a process that is precisely controlled to guarantee efficient compaction of the genome and proper chromosomal segregation during cell division and to accomplish DNA replication, transcription, and repair. Due to the important structural and regulatory roles played by histones, it is not surprising that histone functional dysregulation or aberrant levels of histones can have severe consequences for multiple cellular processes and ultimately might affect development or contribute to cell transformation. Recently, germline frameshift mutations involving the C-terminal tail of HIST1H1E, which is a widely expressed member of the linker histone family and facilitates higher-order chromatin folding, have been causally linked to an as-yet poorly defined syndrome that includes intellectual disability. We report that these mutations result in stable proteins that reside in the nucleus, bind to chromatin, disrupt proper compaction of DNA, and are associated with a specific methylation pattern. Cells expressing these mutant proteins have a dramatically reduced proliferation rate and competence, hardly enter into the S phase, and undergo accelerated senescence. Remarkably, clinical assessment of a relatively large cohort of subjects sharing these mutations revealed a premature aging phenotype as a previously unrecognized feature of the disorder. Our findings identify a direct link between aberrant chromatin remodeling, cellular senescence, and accelerated aging.

}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2019.07.007}, author = {Flex, Elisabetta and Martinelli, Simone and Van Dijck, Anke and Ciolfi, Andrea and Cecchetti, Serena and Coluzzi, Elisa and Pannone, Luca and Andreoli, Cristina and Radio, Francesca Clementina and Pizzi, Simone and Carpentieri, Giovanna and Bruselles, Alessandro and Catanzaro, Giuseppina and Pedace, Lucia and Miele, Evelina and Carcarino, Elena and Ge, Xiaoyan and Chijiwa, Chieko and Lewis, M E Suzanne and Meuwissen, Marije and Kenis, Sandra and Van der Aa, Nathalie and Larson, Austin and Brown, Kathleen and Wasserstein, Melissa P and Skotko, Brian G and Begtrup, Amber and Person, Richard and Karayiorgou, Maria and Roos, J Louw and Van Gassen, Koen L and Koopmans, Marije and Bijlsma, Emilia K and Santen, Gijs W E and Barge-Schaapveld, Daniela Q C M and Ruivenkamp, Claudia A L and Hoffer, Mariette J V and Lalani, Seema R and Streff, Haley and Craigen, William J and Graham, Brett H and van den Elzen, Annette P M and Kamphuis, Daan J and {\~O}unap, Katrin and Reinson, Karit and Pajusalu, Sander and Wojcik, Monica H and Viberti, Clara and Di Gaetano, Cornelia and Bertini, Enrico and Petrucci, Simona and De Luca, Alessandro and Rota, Rossella and Ferretti, Elisabetta and Matullo, Giuseppe and Dallapiccola, Bruno and Sgura, Antonella and Walkiewicz, Magdalena and Kooy, R Frank and Tartaglia, Marco} } @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 {391, title = {Heterozygous variants in ACTL6A, encoding a component of the BAF complex, are associated with intellectual disability.}, journal = {Hum Mutat}, volume = {38}, year = {2017}, month = {2017 10}, pages = {1365-1371}, abstract = {

Pathogenic variants in genes encoding components of the BRG1-associated factor (BAF) chromatin remodeling complex have been associated with intellectual disability syndromes. We identified heterozygous, novel variants in ACTL6A, a gene encoding a component of the BAF complex, in three subjects with varying degrees of intellectual disability. Two subjects have missense variants affecting highly conserved amino acid residues within the actin-like domain. Missense mutations in the homologous region in yeast actin were previously reported to be dominant lethal and were associated with impaired binding of the human ACTL6A to β-actin and BRG1. A third subject has a splicing variant that creates an in-frame deletion. Our findings suggest that the variants identified in our subjects may have a deleterious effect on the function of the protein by disturbing the integrity of the BAF complex. Thus, ACTL6A gene mutation analysis should be considered in patients with intellectual disability, learning disabilities, or developmental language disorder.

}, keywords = {Actins, Adolescent, Child, Chromatin Assembly and Disassembly, Chromosomal Proteins, Non-Histone, DNA Helicases, DNA-Binding Proteins, Exome, Face, Female, Hand Deformities, Congenital, Heterozygote, Humans, Intellectual Disability, Male, Micrognathism, Multiprotein Complexes, Mutation, Missense, Nuclear Proteins, Protein Binding, Transcription Factors}, issn = {1098-1004}, doi = {10.1002/humu.23282}, author = {Marom, Ronit and Jain, Mahim and Burrage, Lindsay C and Song, I-Wen and Graham, Brett H and Brown, Chester W and Stevens, Servi J C and Stegmann, Alexander P A and Gunter, Andrew T and Kaplan, Julie D and Gavrilova, Ralitza H and Shinawi, Marwan and Rosenfeld, Jill A and Bae, Yangjin and Tran, Alyssa A and Chen, Yuqing and Lu, James T and Gibbs, Richard A and Eng, Christine and Yang, Yaping and Rousseau, Justine and de Vries, Bert B A and Campeau, Philippe M and Lee, Brendan} } @article {357, title = {Lessons learned from additional research analyses of unsolved clinical exome cases.}, journal = {Genome Med}, volume = {9}, year = {2017}, month = {2017 03 21}, pages = {26}, abstract = {

BACKGROUND: Given the rarity of most single-gene Mendelian disorders, concerted efforts of data exchange between clinical and scientific communities are critical to optimize molecular diagnosis and novel disease gene discovery.

METHODS: We designed and implemented protocols for the study of cases for which a plausible molecular diagnosis was not achieved in a clinical genomics diagnostic laboratory (i.e. unsolved clinical exomes). Such cases were recruited to a research laboratory for further analyses, in order to potentially: (1) accelerate novel disease gene discovery; (2) increase the molecular diagnostic yield of whole exome sequencing (WES); and (3) gain insight into the genetic mechanisms of disease. Pilot project data included 74 families, consisting mostly of parent-offspring trios. Analyses performed on a research basis employed both WES from additional family members and complementary bioinformatics approaches and protocols.

RESULTS: Analysis of all possible modes of Mendelian inheritance, focusing on both single nucleotide variants (SNV) and copy number variant (CNV) alleles, yielded a likely contributory variant in 36\% (27/74) of cases. If one includes candidate genes with variants identified within a single family, a potential contributory variant was identified in a total of ~51\% (38/74) of cases enrolled in this pilot study. The molecular diagnosis was achieved in 30/63 trios (47.6\%). Besides this, the analysis workflow yielded evidence for pathogenic variants in disease-associated genes in 4/6 singleton cases (66.6\%), 1/1 multiplex family involving three affected siblings, and 3/4 (75\%) quartet families. Both the analytical pipeline and the collaborative efforts between the diagnostic and research laboratories provided insights that allowed recent disease gene discoveries (PURA, TANGO2, EMC1, GNB5, ATAD3A, and MIPEP) and increased the number of novel genes, defined in this study as genes identified in more than one family (DHX30 and EBF3).

CONCLUSION: An efficient genomics pipeline in which clinical sequencing in a diagnostic laboratory is followed by the detailed reanalysis of unsolved cases in a research environment, supplemented with WES data from additional family members, and subject to adjuvant bioinformatics analyses including relaxed variant filtering parameters in informatics pipelines, can enhance the molecular diagnostic yield and provide mechanistic insights into Mendelian disorders. Implementing these approaches requires collaborative clinical molecular diagnostic and research efforts.

}, keywords = {Adenosine Triphosphatases, ATPases Associated with Diverse Cellular Activities, Computational Biology, DNA Copy Number Variations, DNA-Binding Proteins, Exome, Female, Genetic Diseases, Inborn, Genomics, GTP-Binding Protein beta Subunits, Humans, Male, Membrane Proteins, Metalloendopeptidases, Mitochondrial Proteins, Pilot Projects, Polymorphism, Single Nucleotide, Sequence Analysis, DNA, Transcription Factors}, issn = {1756-994X}, doi = {10.1186/s13073-017-0412-6}, author = {Eldomery, Mohammad K and Coban-Akdemir, Zeynep and Harel, Tamar and Rosenfeld, Jill A and Gambin, Tomasz and Stray-Pedersen, Asbj{\o}rg and K{\"u}ry, S{\'e}bastien and Mercier, Sandra and Lessel, Davor and Denecke, Jonas and Wiszniewski, Wojciech and Penney, Samantha and Liu, Pengfei and Bi, Weimin and Lalani, Seema R and Schaaf, Christian P and Wangler, Michael F and Bacino, Carlos A and Lewis, Richard Alan and Potocki, Lorraine and Graham, Brett H and Belmont, John W and Scaglia, Fernando and Orange, Jordan S and Jhangiani, Shalini N and Chiang, Theodore and Doddapaneni, Harsha and Hu, Jianhong and Muzny, Donna M and Xia, Fan and Beaudet, Arthur L and Boerwinkle, Eric and Eng, Christine M and Plon, Sharon E and Sutton, V Reid and Gibbs, Richard A and Posey, Jennifer E and Yang, Yaping and Lupski, James R} } @article {337, title = {Loss of Nardilysin, a Mitochondrial Co-chaperone for α-Ketoglutarate Dehydrogenase, Promotes mTORC1 Activation and Neurodegeneration.}, journal = {Neuron}, volume = {93}, year = {2017}, month = {2017 Jan 04}, pages = {115-131}, abstract = {

We previously identified mutations in Nardilysin (dNrd1) in a forward genetic screen designed to isolate genes whose loss causes neurodegeneration in Drosophila photoreceptor neurons. Here~we show that NRD1 is localized to mitochondria, where it recruits mitochondrial chaperones and assists in the folding of α-ketoglutarate dehydrogenase (OGDH), a rate-limiting enzyme in~the Krebs cycle. Loss of Nrd1 or Ogdh leads to an increase in α-ketoglutarate, a substrate for OGDH,~which in turn leads to mTORC1 activation and a subsequent reduction in autophagy. Inhibition of mTOR activity by rapamycin or partially restoring autophagy delays neurodegeneration in dNrd1 mutant flies. In summary, this study reveals a novel role for NRD1 as a mitochondrial co-chaperone for OGDH and provides a mechanistic link between mitochondrial metabolic dysfunction, mTORC1 signaling, and impaired autophagy in neurodegeneration.

}, keywords = {Animals, Autophagy, Drosophila, Drosophila melanogaster, Drosophila Proteins, Ketoglutarate Dehydrogenase Complex, Ketoglutaric Acids, Lysine, Mechanistic Target of Rapamycin Complex 1, Metalloendopeptidases, Mitochondria, Molecular Chaperones, Multiprotein Complexes, Neurodegenerative Diseases, TOR Serine-Threonine Kinases}, issn = {1097-4199}, doi = {10.1016/j.neuron.2016.11.038}, author = {Yoon, Wan Hee and Sandoval, Hector and Nagarkar-Jaiswal, Sonal and Jaiswal, Manish and Yamamoto, Shinya and Haelterman, Nele A and Putluri, Nagireddy and Putluri, Vasanta and Sreekumar, Arun and Tos, Tulay and Aksoy, Ayse and Donti, Taraka and Graham, Brett H and Ohno, Mikiko and Nishi, Eiichiro and Hunter, Jill and Muzny, Donna M and Carmichael, Jason and Shen, Joseph and Arboleda, Valerie A and Nelson, Stanley F and Wangler, Michael F and Karaca, Ender and Lupski, James R and Bellen, Hugo J} } @article {540, title = {Use of Exome Sequencing for Infants in Intensive Care Units: Ascertainment of Severe Single-Gene Disorders and Effect on Medical Management.}, journal = {JAMA Pediatr}, volume = {171}, year = {2017}, month = {2017 12 04}, pages = {e173438}, abstract = {

Importance: While congenital malformations and genetic diseases are a leading cause of early infant death, to our knowledge, the contribution of single-gene disorders in this group is undetermined.

Objective: To determine the diagnostic yield and use of clinical exome sequencing in critically ill infants.

Design, Setting, and Participants: Clinical exome sequencing was performed for 278 unrelated infants within the first 100 days of life who were admitted to Texas Children{\textquoteright}s Hospital in Houston, Texas, during a 5-year period between December 2011 and January 2017. Exome sequencing types included proband exome, trio exome, and critical trio exome, a rapid genomic assay for seriously ill infants.

Main Outcomes and Measures: Indications for testing, diagnostic yield of clinical exome sequencing, turnaround time, molecular findings, patient age at diagnosis, and effect on medical management among a group of critically ill infants who were suspected to have genetic disorders.

Results: The mean (SEM) age for infants participating in the study was 28.5 (1.7) days; of these, the mean (SEM) age was 29.0 (2.2) days for infants undergoing proband exome sequencing, 31.5 (3.9) days for trio exome, and 22.7 (3.9) days for critical trio exome. Clinical indications for exome sequencing included a range of medical concerns. Overall, a molecular diagnosis was achieved in 102 infants (36.7\%) by clinical exome sequencing, with relatively low yield for cardiovascular abnormalities. The diagnosis affected medical management for 53 infants (52.0\%) and had a substantial effect on informed redirection of care, initiation of new subspecialist care, medication/dietary modifications, and furthering life-saving procedures in select patients. Critical trio exome sequencing revealed a molecular diagnosis in 32 of 63 infants (50.8\%) at a mean (SEM) of 33.1 (5.6) days of life with a mean (SEM) turnaround time of 13.0 (0.4) days. Clinical care was altered by the diagnosis in 23 of 32 patients (71.9\%). The diagnostic yield, patient age at diagnosis, and medical effect in the group that underwent critical trio exome sequencing were significantly different compared with the group who underwent regular exome testing. For deceased infants (n = 81), genetic disorders were molecularly diagnosed in 39 (48.1\%) by exome sequencing, with implications for recurrence risk counseling.

Conclusions and Relevance: Exome sequencing is a powerful tool for the diagnostic evaluation of critically ill infants with suspected monogenic disorders in the neonatal and pediatric intensive care units and its use has a notable effect on clinical decision making.

}, keywords = {Adult, Critical Care, Disease Management, Exome, Genetic Counseling, Genetic Diseases, Inborn, Humans, Infant, Infant Care, Infant, Newborn, Intensive Care Units, Pediatric, Length of Stay, Retrospective Studies, Texas, Whole Exome Sequencing}, issn = {2168-6211}, doi = {10.1001/jamapediatrics.2017.3438}, author = {Meng, Linyan and Pammi, Mohan and Saronwala, Anirudh and Magoulas, Pilar and Ghazi, Andrew Ray and Vetrini, Francesco and Zhang, Jing and He, Weimin and Dharmadhikari, Avinash V and Qu, Chunjing and Ward, Patricia and Braxton, Alicia and Narayanan, Swetha and Ge, Xiaoyan and Tokita, Mari J and Santiago-Sim, Teresa and Dai, Hongzheng and Chiang, Theodore and Smith, Hadley and Azamian, Mahshid S and Robak, Laurie and Bostwick, Bret L and Schaaf, Christian P and Potocki, Lorraine and Scaglia, Fernando and Bacino, Carlos A and Hanchard, Neil A and Wangler, Michael F and Scott, Daryl and Brown, Chester and Hu, Jianhong and Belmont, John W and Burrage, Lindsay C and Graham, Brett H and Sutton, Vernon Reid and Craigen, William J and Plon, Sharon E and Lupski, James R and Beaudet, Arthur L and Gibbs, Richard A and Muzny, Donna M and Miller, Marcus J and Wang, Xia and Leduc, Magalie S and Xiao, Rui and Liu, Pengfei and Shaw, Chad and Walkiewicz, Magdalena and Bi, Weimin and Xia, Fan and Lee, Brendan and Eng, Christine M and Yang, Yaping and Lalani, Seema R} } @article {21, title = {Recurrent De Novo and Biallelic Variation of ATAD3A, Encoding a Mitochondrial Membrane Protein, Results in Distinct Neurological Syndromes.}, journal = {Am J Hum Genet}, volume = {99}, year = {2016}, month = {2016 Oct 06}, pages = {831-845}, abstract = {

ATPase family AAA-domain containing protein 3A (ATAD3A) is a nuclear-encoded mitochondrial membrane protein implicated in mitochondrial dynamics, nucleoid organization, protein translation, cell growth, and cholesterol metabolism. We identified a recurrent de novo ATAD3A c.1582C>T (p.Arg528Trp) variant by whole-exome sequencing (WES) in five unrelated individuals with a core phenotype of global developmental delay, hypotonia, optic atrophy, axonal neuropathy, and hypertrophic cardiomyopathy. We also describe two families with biallelic variants in ATAD3A, including a homozygous variant in two siblings, and biallelic ATAD3A deletions mediated by nonallelic homologous recombination (NAHR) between ATAD3A and gene family members ATAD3B and ATAD3C. Tissue-specific overexpression of bor, the Drosophila mutation homologous to the human c.1582C>T (p.Arg528Trp) variant, resulted in a dramatic decrease in mitochondrial content, aberrant mitochondrial morphology, and increased autophagy. Homozygous null bor larvae showed a significant decrease of mitochondria, while overexpression of bor resulted in larger, elongated mitochondria. Finally, fibroblasts of an affected individual exhibited increased mitophagy. We conclude that the p.Arg528Trp variant functions through a dominant-negative mechanism that results in small mitochondria that trigger mitophagy, resulting in a reduction in mitochondrial content. ATAD3A variation represents an additional link between mitochondrial dynamics and recognizable neurological syndromes, as seen with MFN2, OPA1, DNM1L, and STAT2 mutations.

}, keywords = {Adenosine Triphosphatases, Adult, Alleles, Animals, ATPases Associated with Diverse Cellular Activities, Axons, Cardiomyopathies, Child, Child, Preschool, Developmental Disabilities, DNA Copy Number Variations, Drosophila melanogaster, Female, Fibroblasts, Homozygote, Humans, Infant, Infant, Newborn, Male, Membrane Proteins, Mitochondria, Mitochondrial Proteins, Muscle Hypotonia, Muscles, Mutation, Nervous System Diseases, Neurons, Optic Atrophy, Phenotype, Polymorphism, Single Nucleotide, Syndrome, Young Adult}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2016.08.007}, author = {Harel, Tamar and Yoon, Wan Hee and Garone, Caterina and Gu, Shen and Coban-Akdemir, Zeynep and Eldomery, Mohammad K and Posey, Jennifer E and Jhangiani, Shalini N and Rosenfeld, Jill A and Cho, Megan T and Fox, Stephanie and Withers, Marjorie and Brooks, Stephanie M and Chiang, Theodore and Duraine, Lita and Erdin, Serkan and Yuan, Bo and Shao, Yunru and Moussallem, Elie and Lamperti, Costanza and Donati, Maria A and Smith, Joshua D and McLaughlin, Heather M and Eng, Christine M and Walkiewicz, Magdalena and Xia, Fan and Pippucci, Tommaso and Magini, Pamela and Seri, Marco and Zeviani, Massimo and Hirano, Michio and Hunter, Jill V and Srour, Myriam and Zanigni, Stefano and Lewis, Richard Alan and Muzny, Donna M and Lotze, Timothy E and Boerwinkle, Eric and Gibbs, Richard A and Hickey, Scott E and Graham, Brett H and Yang, Yaping and Buhas, Daniela and Martin, Donna M and Potocki, Lorraine and Graziano, Claudio and Bellen, Hugo J and Lupski, James R} } @article {134, title = {Expanding the Molecular and Clinical Phenotype of SSR4-CDG.}, journal = {Hum Mutat}, volume = {36}, year = {2015}, month = {2015 Nov}, pages = {1048-51}, abstract = {

Congenital disorders of glycosylation (CDG) are a group of mostly autosomal recessive disorders primarily characterized by neurological abnormalities. Recently, we described a single CDG patient with a de novo mutation in the X-linked gene, Signal Sequence Receptor 4 (SSR4). We performed whole-exome sequencing to identify causal variants in several affected individuals who had either an undifferentiated neurological disorder or unsolved CDG of unknown etiology based on abnormal transferrin glycosylation. We now report eight affected males with either de novo (4) or inherited (4) loss of function mutations in SSR4. Western blot analysis revealed that the mutations caused a complete loss of SSR4 protein. In nearly all cases, the abnormal glycosylation of serum transferrin was only slightly above the accepted normal cutoff range.

}, keywords = {Calcium-Binding Proteins, Congenital Disorders of Glycosylation, DNA Mutational Analysis, Exome, Gene Order, Genes, X-Linked, Genetic Loci, Humans, Male, Membrane Glycoproteins, Mutation, Phenotype, Receptors, Cytoplasmic and Nuclear, Receptors, Peptide}, issn = {1098-1004}, doi = {10.1002/humu.22856}, author = {Ng, Bobby G and Raymond, Kimiyo and Kircher, Martin and Buckingham, Kati J and Wood, Tim and Shendure, Jay and Nickerson, Deborah A and Bamshad, Michael J and Wong, Jonathan T S and Monteiro, Fabiola Paoli and Graham, Brett H and Jackson, Sheryl and Sparkes, Rebecca and Scheuerle, Angela E and Cathey, Sara and Kok, Fernando and Gibson, James B and Freeze, Hudson H} }