@article {1019, title = {Association of De Novo Variants With Childhood Onset Moyamoya Disease and Diffuse Occlusive Vasculopathy.}, journal = {Neurology}, volume = {96}, year = {2021}, month = {2021 03 30}, pages = {e1783-e1791}, abstract = {

OBJECTIVE: To test the hypothesis that de novo genetic variants are responsible for moyamoya disease (MMD) in children with unaffected relatives, we performed exome sequencing of 28 affected children and their unaffected parents.

METHODS: Exome sequencing was performed on 28 trios of affected patients with MMD and unaffected parents.

RESULTS: We identified 3 novel rare de novo variants, 1 in the RING domain and 2 in a highly conserved region distal to the RING domain (4,114-4,120). These de novo cases of MMD present at a young age with aggressive MMD and uniquely have additional occlusive vascular lesions, including renal artery stenosis. Two previously reported cases had de novo variants in the same limited region and presented young with aggressive MMD, and 1 case had narrowing of the inferior abdominal aorta.

CONCLUSIONS: These results indicate a novel syndrome associated with rare variants defined by de novo mutations disrupting highly conserved amino acids in the RING domain and a discrete region distal to the RING domain delimited by amino acids 4,114 to 4,120 leading to onset of severe MMD before 3 years of age and occlusion of other arteries, including the abdominal aorta, renal, iliac, and femoral arteries.

}, keywords = {Adenosine Triphosphatases, Adult, Age of Onset, Aortic Diseases, Arterial Occlusive Diseases, Child, Preschool, Female, Femoral Artery, Humans, Iliac Artery, Male, Moyamoya Disease, Mutation, Renal Artery Obstruction, Ubiquitin-Protein Ligases}, issn = {1526-632X}, doi = {10.1212/WNL.0000000000011653}, author = {Pinard, Amelie and Fiander, Maximillian D J and Cecchi, Alana C and Rideout, Andrea L and Azouz, Mohamed and Fraser, Stuart M and McNeely, P Daniel and Walling, Simon and Novara, Sarah C and Hurst, Anna C E and Guo, Dongchuan and Parkash, Sandhya and Bamshad, Michael J and Nickerson, Deborah A and Vandersteen, Anthony M and Milewicz, Dianna M} } @article {424, title = {De Novo Missense Mutations in DHX30 Impair Global Translation and Cause a Neurodevelopmental Disorder.}, journal = {Am J Hum Genet}, volume = {101}, year = {2017}, month = {2017 Nov 02}, pages = {716-724}, abstract = {

DHX30 is a member of the family of DExH-box helicases, which use ATP hydrolysis to unwind RNA secondary structures. Here we identified six different de novo missense mutations in DHX30 in twelve unrelated individuals affected by global developmental delay (GDD), intellectual disability (ID), severe speech impairment and gait abnormalities. While four mutations are recurrent, two are unique with one affecting the codon of one recurrent mutation. All amino acid changes are located within highly conserved helicase motifs and were found to either impair ATPase activity or RNA recognition in different in~vitro assays. Moreover, protein variants exhibit an increased propensity to trigger stress granule (SG) formation resulting in global translation inhibition. Thus, our findings highlight the prominent role of translation control in development and function of the central nervous system and also provide molecular insight into how DHX30 dysfunction might cause a neurodevelopmental disorder.

}, keywords = {Adenosine Triphosphatases, Adolescent, Amino Acids, Cell Line, Cell Line, Tumor, Central Nervous System, Child, Child, Preschool, Developmental Disabilities, Female, HEK293 Cells, Humans, Intellectual Disability, Male, Mutation, Missense, RNA, RNA Helicases}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2017.09.014}, author = {Lessel, Davor and Schob, Claudia and K{\"u}ry, S{\'e}bastien and Reijnders, Margot R F and Harel, Tamar and Eldomery, Mohammad K and Coban-Akdemir, Zeynep and Denecke, Jonas and Edvardson, Shimon and Colin, Estelle and Stegmann, Alexander P A and Gerkes, Erica H and Tessarech, Marine and Bonneau, Dominique and Barth, Magalie and Besnard, Thomas and Cogn{\'e}, Benjamin and Revah-Politi, Anya and Strom, Tim M and Rosenfeld, Jill A and Yang, Yaping and Posey, Jennifer E and Immken, LaDonna and Oundjian, Nelly and Helbig, Katherine L and Meeks, Naomi and Zegar, Kelsey and Morton, Jenny and Schieving, Jolanda H and Claasen, Ana and Huentelman, Matthew and Narayanan, Vinodh and Ramsey, Keri and Brunner, Han G and Elpeleg, Orly and Mercier, Sandra and B{\'e}zieau, St{\'e}phane and Kubisch, Christian and Kleefstra, Tjitske and Kindler, Stefan and Lupski, James R and Kreienkamp, Hans-J{\"u}rgen} } @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 {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 {231, title = {The Alu-rich genomic architecture of SPAST predisposes to diverse and functionally distinct disease-associated CNV alleles.}, journal = {Am J Hum Genet}, volume = {95}, year = {2014}, month = {2014 Aug 07}, pages = {143-61}, abstract = {

Intragenic copy-number variants (CNVs) contribute to the allelic spectrum of both Mendelian and complex disorders. Although pathogenic deletions and duplications in SPAST (mutations in which cause autosomal-dominant spastic paraplegia 4 [SPG4]) have been described, their origins and molecular consequences remain obscure. We mapped breakpoint junctions of 54 SPAST CNVs at nucleotide resolution. Diverse combinations of exons are deleted or duplicated, highlighting the importance of particular exons for spastin function. Of the 54 CNVs, 38 (70\%) appear to be mediated by an Alu-based mechanism, suggesting that the Alu-rich genomic architecture of SPAST renders this locus susceptible to various genome rearrangements. Analysis of breakpoint Alus further informs a model of Alu-mediated CNV formation characterized by small CNV size and potential involvement of mechanisms other than homologous recombination. Twelve deletions (22\%) overlap part of SPAST and a portion of a nearby, directly oriented gene, predicting novel chimeric genes in these subjects{\textquoteright} genomes. cDNA from a subject with a SPAST final exon deletion contained multiple SPAST:SLC30A6 fusion transcripts, indicating that SPAST CNVs can have transcriptional effects beyond the gene itself. SLC30A6 has been implicated in Alzheimer disease, so these fusion gene data could explain a report of spastic paraplegia and dementia cosegregating in a family with deletion of the final exon of SPAST. Our findings provide evidence that the Alu genomic architecture of SPAST predisposes to diverse CNV alleles with distinct transcriptional--and possibly phenotypic--consequences. Moreover, we provide further mechanistic insights into Alu-mediated copy-number change that are extendable to other loci.

}, keywords = {Adenosine Triphosphatases, Alu Elements, Base Sequence, Cation Transport Proteins, Cell Line, Transformed, DNA Copy Number Variations, Genotype, Humans, Protein Isoforms, Recombinant Fusion Proteins, Sequence Analysis, DNA, Sequence Deletion, Spastic Paraplegia, Hereditary, Spastin}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2014.06.014}, author = {Boone, Philip M and Yuan, Bo and Campbell, Ian M and Scull, Jennifer C and Withers, Marjorie A and Baggett, Brett C and Beck, Christine R and Shaw, Christine J and Stankiewicz, Pawel and Moretti, Paolo and Goodwin, Wendy E and Hein, Nichole and Fink, John K and Seong, Moon-Woo and Seo, Soo Hyun and Park, Sung Sup and Karbassi, Izabela D and Batish, Sat Dev and Ord{\'o}{\~n}ez-Ugalde, Andr{\'e}s and Quint{\'a}ns, Beatriz and Sobrido, Mar{\'\i}a-Jes{\'u}s and Stemmler, Susanne and Lupski, James R} } @article {203, title = {Mutations in KATNB1 cause complex cerebral malformations by disrupting asymmetrically dividing neural progenitors.}, journal = {Neuron}, volume = {84}, year = {2014}, month = {2014 Dec 17}, pages = {1226-39}, abstract = {

Exome sequencing analysis of over 2,000 children with complex malformations of cortical development identified five independent (four homozygous and one compound heterozygous) deleterious mutations in KATNB1, encoding the regulatory subunit of the microtubule-severing enzyme Katanin. Mitotic spindle formation is defective in patient-derived fibroblasts, a consequence of disrupted interactions of mutant KATNB1 with KATNA1, the catalytic subunit of Katanin, and other microtubule-associated proteins. Loss of KATNB1 orthologs in zebrafish (katnb1) and flies (kat80) results in microcephaly, recapitulating the human phenotype. In the developing Drosophila optic lobe, kat80 loss specifically affects the asymmetrically dividing neuroblasts, which display supernumerary centrosomes and spindle abnormalities during mitosis, leading to cell cycle progression delays and reduced cell numbers. Furthermore, kat80 depletion results in dendritic arborization defects in sensory and motor neurons, affecting neural architecture. Taken together, we provide insight into the mechanisms by which KATNB1 mutations cause human cerebral cortical malformations, demonstrating its fundamental role during brain development.

}, keywords = {Adenosine Triphosphatases, Animals, Brain, Cell Count, Cell Division, Dendrites, Drosophila, Drosophila Proteins, Humans, Katanin, Mice, Microcephaly, Microtubule-Associated Proteins, Mutation, Neural Stem Cells, Neurogenesis, Optic Lobe, Nonmammalian, Spindle Apparatus, Zebrafish}, issn = {1097-4199}, doi = {10.1016/j.neuron.2014.12.014}, author = {Mishra-Gorur, Ketu and {\c C}a{\u g}layan, Ahmet Okay and Schaffer, Ashleigh E and Chabu, Chiswili and Henegariu, Octavian and Vonhoff, Fernando and Akg{\"u}m{\"u}{\c s}, G{\"o}zde Tu{\u g}ce and Nishimura, Sayoko and Han, Wenqi and Tu, Shu and Baran, Bur{\c c}in and G{\"u}m{\"u}{\c s}, Hakan and Dilber, Cengiz and Zaki, Maha S and Hossni, Heba A A and Rivi{\`e}re, Jean-Baptiste and Kayserili, H{\"u}lya and Spencer, Emily G and Rosti, Rasim O and Schroth, Jana and Per, H{\"u}seyin and Caglar, Caner and {\c C}a{\u g}lar, {\c C}a{\u g}ri and D{\"o}len, Duygu and Baranoski, Jacob F and Kumanda{\c s}, Sefer and Minja, Frank J and Erson-Omay, E Zeynep and Mane, Shrikant M and Lifton, Richard P and Xu, Tian and Keshishian, Haig and Dobyns, William B and Chi, Neil C and {\v S}estan, Nenad and Louvi, Angeliki and Bilguvar, Kaya and Yasuno, Katsuhito and Gleeson, Joseph G and G{\"u}nel, Murat} } @article {219, title = {RNF213 rare variants in an ethnically diverse population with Moyamoya disease.}, journal = {Stroke}, volume = {45}, year = {2014}, month = {2014 Nov}, pages = {3200-7}, abstract = {

BACKGROUND AND PURPOSE: Moyamoya disease (MMD) is a rare, genetically heterogeneous cerebrovascular disease resulting from occlusion of the distal internal carotid arteries. A variant in the Ring Finger 213 gene (RNF213), altering arginine at position 4810 (p.R4810K), is associated with MMD in Asian populations. However, there are a lack of data on the role of RNF213 in patients with MMD of additional ethnicities and diasporic Asian populations. We investigate the contribution of RNF213 alterations to MMD in an ethnically diverse population based in the United States.

METHODS: We initially sequenced RNF213 exons 43, 44, and 45 (encoding the eponymous RING finger domain) and exon 60 (encoding p.R4810K) in 86 ethnically diverse patients with MMD. Comprehensive exome sequencing data from 24 additional patients with MMD was then analyzed to identify RNF213 variants globally. Segregation of variants with MMD and other vascular diseases was assessed in families.

RESULTS: RNF213 p.R4810K was identified in 56\% (9/16) of patients with MMD of Asian descent and not in 94 patients of non-Asian descent. 3.6\% (4/110) of patients had variants in the exons encoding the RING finger domain. Seven additional variants were identified in 29\% (7/24) of patients with MMD who underwent exome sequencing. Segregation analysis supported an association with MMD for 2 variants and a lack of association with disease for 1 variant.

CONCLUSIONS: These results confirm that alterations in RNF213 predispose patients of diverse ethnicities to MMD, and that the p.R4810K variant predisposes individuals of Asian descent in the United States to MMD.

}, keywords = {Adenosine Triphosphatases, Adolescent, Adult, Child, Cohort Studies, Ethnic Groups, Female, Genetic Variation, Humans, Male, Moyamoya Disease, Population Surveillance, Ubiquitin-Protein Ligases, Young Adult}, issn = {1524-4628}, doi = {10.1161/STROKEAHA.114.006244}, author = {Cecchi, Alana C and Guo, Dongchuan and Ren, Zhao and Flynn, Kelly and Santos-Cortez, Regie Lyn P and Leal, Suzanne M and Wang, Gao T and Regalado, Ellen S and Steinberg, Gary K and Shendure, Jay and Bamshad, Michael J and Grotta, James C and Nickerson, Deborah A and Pannu, Hariyadarshi and Milewicz, Dianna M} }