@article {850, title = {Analysis of cardiac magnetic resonance imaging in 36,000 individuals yields genetic insights into dilated cardiomyopathy.}, journal = {Nat Commun}, volume = {11}, year = {2020}, month = {2020 05 07}, pages = {2254}, abstract = {

Dilated cardiomyopathy (DCM) is an important cause of heart failure and the leading indication for heart transplantation. Many rare genetic variants have been associated with DCM, but common variant studies of the disease have yielded few associated loci. As structural changes in the heart are a defining feature of DCM, we report a genome-wide association study of cardiac magnetic resonance imaging (MRI)-derived left ventricular measurements in 36,041 UK Biobank participants, with replication in 2184 participants from the Multi-Ethnic Study of Atherosclerosis. We identify 45 previously unreported loci associated with cardiac structure and function, many near well-established genes for Mendelian cardiomyopathies. A polygenic score of MRI-derived left ventricular end systolic volume strongly associates with incident DCM in the general population. Even among carriers of TTN truncating mutations, this polygenic score influences the size and function of the human heart. These results further implicate common genetic polymorphisms in the pathogenesis of DCM.

}, keywords = {Cardiomyopathy, Dilated, Genome-Wide Association Study, Heart, Humans, Magnetic Resonance Imaging, Myocardium, Polymorphism, Single Nucleotide}, issn = {2041-1723}, doi = {10.1038/s41467-020-15823-7}, author = {Pirruccello, James P and Bick, Alexander and Wang, Minxian and Chaffin, Mark and Friedman, Samuel and Yao, Jie and Guo, Xiuqing and Venkatesh, Bharath Ambale and Taylor, Kent D and Post, Wendy S and Rich, Stephen and Lima, Joao A C and Rotter, Jerome I and Philippakis, Anthony and Lubitz, Steven A and Ellinor, Patrick T and Khera, Amit V and Kathiresan, Sekar and Aragam, Krishna G} } @article {864, title = {Combining Imaging and Genetics to Predict Recurrence of Anticoagulation-Associated Intracerebral Hemorrhage.}, journal = {Stroke}, volume = {51}, year = {2020}, month = {2020 07}, pages = {2153-2160}, abstract = {

BACKGROUND AND PURPOSE: For survivors of oral anticoagulation therapy (OAT)-associated intracerebral hemorrhage (OAT-ICH) who are at high risk for thromboembolism, the benefits of OAT resumption must be weighed against increased risk of recurrent hemorrhagic stroke. The ε2/ε4 alleles of the () gene, MRI-defined cortical superficial siderosis, and cerebral microbleeds are the most potent risk factors for recurrent ICH. We sought to determine whether combining MRI markers and genotype could have clinical impact by identifying ICH survivors in whom the risks of OAT resumption are highest.

METHODS: Joint analysis of data from 2 longitudinal cohort studies of OAT-ICH survivors: (1) MGH-ICH study (Massachusetts General Hospital ICH) and (2) longitudinal component of the ERICH study (Ethnic/Racial Variations of Intracerebral Hemorrhage). We evaluated whether MRI markers and genotype predict ICH recurrence. We then developed and validated a combined -MRI classification scheme to predict ICH recurrence, using Classification and Regression Tree analysis.

RESULTS: Cortical superficial siderosis, cerebral microbleed, and ε2/ε4 variants were independently associated with ICH recurrence after OAT-ICH (all <0.05). Combining genotype and MRI data resulted in improved prediction of ICH recurrence (Harrell C: 0.79 versus 0.55 for clinical data alone, =0.033). In the MGH (training) data set, CSS, cerebral microbleed, and ε2/ε4 stratified likelihood of ICH recurrence into high-, medium-, and low-risk categories. In the ERICH (validation) data set, yearly ICH recurrence rates for high-, medium-, and low-risk individuals were 6.6\%, 2.5\%, and 0.9\%, respectively, with overall area under the curve of 0.91 for prediction of recurrent ICH.

CONCLUSIONS: Combining MRI and genotype stratifies likelihood of ICH recurrence into high, medium, and low risk. If confirmed in prospective studies, this combined -MRI classification scheme may prove useful for selecting individuals for OAT resumption after ICH.

}, keywords = {Aged, Anticoagulants, Apolipoprotein E4, Cerebral Hemorrhage, Female, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Neuroimaging, Recurrence}, issn = {1524-4628}, doi = {10.1161/STROKEAHA.120.028310}, author = {Biffi, Alessandro and Urday, Sebastian and Kubiszewski, Patryk and Gilkerson, Lee and Sekar, Padmini and Rodriguez-Torres, Axana and Bettin, Margaret and Charidimou, Andreas and Pasi, Marco and Kourkoulis, Christina and Schwab, Kristin and DiPucchio, Zora and Behymer, Tyler and Osborne, Jennifer and Morgan, Misty and Moomaw, Charles J and James, Michael L and Greenberg, Steven M and Viswanathan, Anand and Gurol, M Edip and Worrall, Bradford B and Testai, Fernando D and McCauley, Jacob L and Falcone, Guido J and Langefeld, Carl D and Anderson, Christopher D and Kamel, Hooman and Woo, Daniel and Sheth, Kevin N and Rosand, Jonathan} } @article {757, title = {Gomez-L{\'o}pez-Hern{\'a}ndez syndrome: A case report with clinical and molecular evaluation and literature review.}, journal = {Am J Med Genet A}, volume = {182}, year = {2020}, month = {2020 07}, pages = {1761-1766}, abstract = {

Gomez-L{\'o}pez-Hern{\'a}ndez syndrome (GLHS) is characterized by rhombencephalosynapsis (RES), alopecia, trigeminal anesthesia and a distinctive phenotype, including brachyturricephaly. It has been suggested that GLHS should be considered as part of the spectrum of RES-associated conditions that include alopecia, trigeminal anesthesia, and craniofacial anomalies, rather than a distinct entity. To the best of our knowledge, 57 patients with GLHS have been described. Despite its first description in 1979, the etiology of this syndrome remains unknown. Here, we describe, to our knowledge, the first case of a patient with GLHS who was molecularly evaluated and had been prenatally exposed to misoprostol. We also reviewed the clinical and morphological features of the patients described to date to better delineate the phenotype and focus on any evidence for adverse pregnancy outcomes or exposure, including teratogens.

}, keywords = {Abnormalities, Multiple, Alopecia, Cerebellum, Child, Child, Preschool, Craniofacial Abnormalities, Female, Growth Disorders, Humans, Magnetic Resonance Imaging, Misoprostol, Neurocutaneous Syndromes, Phenotype, Rhombencephalon, Trigeminal Nerve}, issn = {1552-4833}, doi = {10.1002/ajmg.a.61594}, author = {Perrone, Eduardo and D{\textquoteright}Almeida, V{\^a}nia and de Macena Sobreira, Nara Lygia and de Mello, Claudia Berlim and de Oliveira, Allan Chiaratti and Burlin, St{\^e}nio and Soares, Maria de F{\'a}tima de Faria and Cernach, Mirlene Cec{\'\i}lia Soares Pinho and Alvarez Perez, Ana Beatriz} } @article {770, title = {MN1 C-terminal truncation syndrome is a novel neurodevelopmental and craniofacial disorder with partial rhombencephalosynapsis.}, journal = {Brain}, volume = {143}, year = {2020}, month = {2020 01 01}, pages = {55-68}, abstract = {

MN1 encodes a transcriptional co-regulator without homology to other proteins, previously implicated in acute myeloid leukaemia and development of the palate. Large deletions encompassing MN1 have been reported in individuals with variable neurodevelopmental anomalies and non-specific facial features. We identified a cluster of de novo truncating mutations in MN1 in a cohort of 23 individuals with strikingly similar dysmorphic facial features, especially midface hypoplasia, and intellectual disability with severe expressive language delay. Imaging revealed an atypical form of rhombencephalosynapsis, a distinctive brain malformation characterized by partial or complete loss of the cerebellar vermis with fusion of the cerebellar hemispheres, in 8/10 individuals. Rhombencephalosynapsis has no previously known definitive genetic or environmental causes. Other frequent features included perisylvian polymicrogyria, abnormal posterior clinoid processes and persistent trigeminal artery. MN1 is encoded by only two exons. All mutations, including the recurrent variant p.Arg1295* observed in 8/21 probands, fall in the terminal exon or the extreme 3{\textquoteright} region of exon 1, and are therefore predicted to result in escape from nonsense-mediated mRNA decay. This was confirmed in fibroblasts from three individuals. We propose that the condition described here, MN1 C-terminal truncation (MCTT) syndrome, is not due to MN1 haploinsufficiency but rather is the result of dominantly acting C-terminally truncated MN1 protein. Our data show that MN1 plays a critical role in human craniofacial and brain development, and opens the door to understanding the biological mechanisms underlying rhombencephalosynapsis.

}, keywords = {Abnormalities, Multiple, Adolescent, Basilar Artery, Carotid Arteries, Cerebellar Vermis, Cerebellum, Child, Child, Preschool, Cohort Studies, Comparative Genomic Hybridization, Craniofacial Abnormalities, Female, Fibroblasts, Humans, Imaging, Three-Dimensional, Infant, Intellectual Disability, Language Development Disorders, Magnetic Resonance Imaging, Male, Middle Aged, Mutation, Nervous System Malformations, Nonsense Mediated mRNA Decay, Polymicrogyria, Real-Time Polymerase Chain Reaction, RNA-Seq, Syndrome, Tomography, X-Ray Computed, Trans-Activators, Tumor Suppressor Proteins, Whole Exome Sequencing, Whole Genome Sequencing}, issn = {1460-2156}, doi = {10.1093/brain/awz379}, author = {Mak, Christopher C Y and Doherty, Dan and Lin, Angela E and Vegas, Nancy and Cho, Megan T and Viot, G{\'e}raldine and Dimartino, Cl{\'e}mantine and Weisfeld-Adams, James D and Lessel, Davor and Joss, Shelagh and Li, Chumei and Gonzaga-Jauregui, Claudia and Zarate, Yuri A and Ehmke, Nadja and Horn, Denise and Troyer, Caitlin and Kant, Sarina G and Lee, Youngha and Ishak, Gisele E and Leung, Gordon and Barone Pritchard, Amanda and Yang, Sandra and Bend, Eric G and Filippini, Francesca and Roadhouse, Chelsea and Lebrun, Nicolas and Mehaffey, Michele G and Martin, Pierre-Marie and Apple, Benjamin and Millan, Francisca and Puk, Oliver and Hoffer, Mariette J V and Henderson, Lindsay B and McGowan, Ruth and Wentzensen, Ingrid M and Pei, Steven and Zahir, Farah R and Yu, Mullin and Gibson, William T and Seman, Ann and Steeves, Marcie and Murrell, Jill R and Luettgen, Sabine and Francisco, Elizabeth and Strom, Tim M and Amlie-Wolf, Louise and Kaindl, Angela M and Wilson, William G and Halbach, Sara and Basel-Salmon, Lina and Lev-El, Noa and Denecke, Jonas and Vissers, Lisenka E L M and Radtke, Kelly and Chelly, Jamel and Zackai, Elaine and Friedman, Jan M and Bamshad, Michael J and Nickerson, Deborah A and Reid, Russell R and Devriendt, Koenraad and Chae, Jong-Hee and Stolerman, Elliot and McDougall, Carey and Powis, Z{\"o}e and Bienvenu, Thierry and Tan, Tiong Y and Orenstein, Naama and Dobyns, William B and Shieh, Joseph T and Choi, Murim and Waggoner, Darrel and Gripp, Karen W and Parker, Michael J and Stoler, Joan and Lyonnet, Stanislas and Cormier-Daire, Val{\'e}rie and Viskochil, David and Hoffman, Trevor L and Amiel, Jeanne and Chung, Brian H Y and Gordon, Christopher T} } @article {910, title = {Pathogenic Variants in CEP85L Cause Sporadic and Familial Posterior Predominant Lissencephaly.}, journal = {Neuron}, volume = {106}, year = {2020}, month = {2020 04 22}, pages = {237-245.e8}, abstract = {

Lissencephaly (LIS), denoting a "smooth brain," is characterized by the absence of normal cerebral convolutions with abnormalities of cortical thickness. Pathogenic variants in over 20 genes are associated with LIS. The majority of posterior predominant LIS is caused by pathogenic variants in LIS1~(also known as PAFAH1B1), although a significant fraction remains without a known genetic etiology. We now implicate CEP85L as an important cause of~posterior predominant LIS, identifying 13 individuals with rare, heterozygous CEP85L variants, including 2 families with autosomal dominant inheritance. We show that CEP85L is a centrosome protein localizing to the pericentriolar material, and knockdown of Cep85l causes a neuronal migration defect in mice. LIS1 also localizes to the centrosome, suggesting that this organelle is key to the mechanism of posterior predominant LIS.

}, keywords = {Adolescent, Adult, Age of Onset, Animals, Centrosome, Child, Child, Preschool, Chromosome Aberrations, Classical Lissencephalies and Subcortical Band Heterotopias, Cytoskeletal Proteins, Female, Gene Knockdown Techniques, Genetic Variation, Heterozygote, Humans, Infant, Magnetic Resonance Imaging, Male, Mice, Mutation, Oncogene Proteins, Fusion, Pedigree, Seizures, Young Adult}, issn = {1097-4199}, doi = {10.1016/j.neuron.2020.01.027}, author = {Tsai, Meng-Han and Muir, Alison M and Wang, Won-Jing and Kang, Yi-Ning and Yang, Kun-Chuan and Chao, Nian-Hsin and Wu, Mei-Feng and Chang, Ying-Chao and Porter, Brenda E and Jansen, Laura A and Sebire, Guillaume and Deconinck, Nicolas and Fan, Wen-Lang and Su, Shih-Chi and Chung, Wen-Hung and Almanza Fuerte, Edith P and Mehaffey, Michele G and Ng, Ching-Ching and Chan, Chung-Kin and Lim, Kheng-Seang and Leventer, Richard J and Lockhart, Paul J and Riney, Kate and Damiano, John A and Hildebrand, Michael S and Mirzaa, Ghayda M and Dobyns, William B and Berkovic, Samuel F and Scheffer, Ingrid E and Tsai, Jin-Wu and Mefford, Heather C} } @article {940, title = {Polymicrogyria is Associated With Pathogenic Variants in PTEN.}, journal = {Ann Neurol}, volume = {88}, year = {2020}, month = {2020 12}, pages = {1153-1164}, abstract = {

OBJECTIVE: Congenital structural brain malformations have been described in patients with pathogenic phosphatase and tensin homologue (PTEN) variants, but the frequency of cortical malformations in patients with PTEN variants and their impact on clinical phenotype are not well understood. Our goal was to systematically characterize brain malformations in patients with PTEN variants and assess the relevance of their brain malformations to clinical presentation.

METHODS: We systematically searched a local radiology database for patients with PTEN variants who had available brain magnetic resonance imaging (MRI). The MRI scans were reviewed systematically for cortical abnormalities. We reviewed electroencephalogram (EEG) data and evaluated the electronic medical record for evidence of epilepsy and developmental delay.

RESULTS: In total, we identified 22 patients with PTEN pathogenic variants for which brain MRIs were available (age range 0.4-17 years). Twelve among these 22 patients (54\%) had polymicrogyria (PMG). Variants associated with PMG or atypical gyration encoded regions of the phosphatase or C2 domains of PTEN. Interestingly, epilepsy was present in only 2 of the 12 patients with PMG. We found a trend toward higher rates of global developmental delay (GDD), intellectual disability (ID), and motor delay in individuals with cortical abnormalities, although cohort size limited statistical significance.

INTERPRETATION: Malformations of cortical development, PMG in particular, represent an under-recognized phenotype associated with PTEN pathogenic variants and may have an association with cognitive and motor delays. Epilepsy was infrequent compared to the previously reported high risk of epilepsy in patients with PMG. ANN NEUROL 2020;88:1153-1164.

}, keywords = {Adolescent, Brain, Child, Child, Preschool, Comorbidity, Databases, Genetic, Developmental Disabilities, Electroencephalography, Female, Humans, Infant, Intellectual Disability, Magnetic Resonance Imaging, Male, Massachusetts, Neuroimaging, Polymicrogyria, PTEN Phosphohydrolase}, issn = {1531-8249}, doi = {10.1002/ana.25904}, author = {Shao, Diane D and Achkar, Christelle M and Lai, Abbe and Srivastava, Siddharth and Doan, Ryan N and Rodan, Lance H and Chen, Allen Y and Poduri, Annapurna and Yang, Edward and Walsh, Christopher A} } @article {760, title = {Prenatal Diagnosis of a Ventral Abdominal Wall Defect.}, journal = {Neoreviews}, volume = {21}, year = {2020}, month = {2020 04}, pages = {e286-e292}, keywords = {Abnormalities, Multiple, Echocardiography, Fatal Outcome, Female, Hernia, Abdominal, Hernia, Diaphragmatic, Hernia, Ventral, Humans, Infant, Newborn, Magnetic Resonance Imaging, Pregnancy, Prenatal Diagnosis, Ultrasonography, Prenatal}, issn = {1526-9906}, doi = {10.1542/neo.21-4-e286}, author = {Beam, Kristyn and Wojcik, Monica H and Agrawal, Pankaj B and Smithers, Charles and Estroff, Judy} } @article {491, title = {Dual Molecular Effects of Dominant RORA Mutations Cause Two Variants of Syndromic Intellectual Disability with Either Autism or Cerebellar Ataxia.}, journal = {Am J Hum Genet}, volume = {102}, year = {2018}, month = {2018 05 03}, pages = {744-759}, abstract = {

RORα, the RAR-related orphan nuclear receptor alpha, is essential for cerebellar development. The spontaneous mutant mouse staggerer, with an ataxic gait caused by neurodegeneration of cerebellar Purkinje cells, was discovered two decades ago to result from homozygous intragenic Rora deletions. However, RORA mutations were hitherto undocumented in humans. Through a multi-centric collaboration, we identified three copy-number variant deletions (two de novo and one dominantly inherited in three generations), one de novo disrupting duplication, and nine de novo point mutations (three truncating, one canonical splice site, and five missense mutations) involving RORA in 16 individuals from 13 families with variable neurodevelopmental delay and intellectual disability (ID)-associated autistic features, cerebellar ataxia, and epilepsy. Consistent with the human and mouse data, disruption of the D.~rerio ortholog, roraa, causes significant reduction in the size of the developing cerebellum. Systematic in~vivo complementation studies showed that, whereas wild-type human RORA mRNA could complement the cerebellar pathology, missense variants had two distinct pathogenic mechanisms of either haploinsufficiency or a dominant toxic effect according to their localization in the ligand-binding or DNA-binding domains, respectively. This dichotomous direction of effect is likely relevant to the phenotype in humans: individuals with loss-of-function variants leading to haploinsufficiency show ID with autistic features, while individuals with de novo dominant toxic variants present with ID, ataxia, and cerebellar atrophy. Our combined genetic and functional data highlight the complex mutational landscape at the human RORA locus and suggest that dual mutational effects likely determine phenotypic outcome.

}, keywords = {Adolescent, Adult, Aged, 80 and over, Alleles, Animals, Autistic Disorder, Brain, Cerebellar Ataxia, Child, Child, Preschool, Disease Models, Animal, DNA Copy Number Variations, Female, Genes, Dominant, Genetic Complementation Test, Humans, Intellectual Disability, Larva, Magnetic Resonance Imaging, Male, Middle Aged, Mutation, Missense, Nuclear Receptor Subfamily 1, Group F, Member 1, Purkinje Cells, Syndrome, Zebrafish}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2018.02.021}, author = {Guissart, Claire and Latypova, X{\'e}nia and Rollier, Paul and Khan, Tahir N and Stamberger, Hannah and McWalter, Kirsty and Cho, Megan T and Kjaergaard, Susanne and Weckhuysen, Sarah and Lesca, Gaetan and Besnard, Thomas and {\~O}unap, Katrin and Schema, Lynn and Chiocchetti, Andreas G and McDonald, Marie and de Bellescize, Julitta and Vincent, Marie and Van Esch, Hilde and Sattler, Shannon and Forghani, Irman and Thiffault, Isabelle and Freitag, Christine M and Barbouth, Deborah Sara and Cadieux-Dion, Maxime and Willaert, Rebecca and Guillen Sacoto, Maria J and Safina, Nicole P and Dubourg, Christ{\`e}le and Grote, Lauren and Carr{\'e}, Wilfrid and Saunders, Carol and Pajusalu, Sander and Farrow, Emily and Boland, Anne and Karlowicz, Danielle Hays and Deleuze, Jean-Fran{\c c}ois and Wojcik, Monica H and Pressman, Rena and Isidor, Bertrand and Vogels, Annick and Van Paesschen, Wim and Al-Gazali, Lihadh and Al Shamsi, Aisha Mohamed and Claustres, Mireille and Pujol, Aurora and Sanders, Stephan J and Rivier, Fran{\c c}ois and Leboucq, Nicolas and Cogn{\'e}, Benjamin and Sasorith, Souphatta and Sanlaville, Damien and Retterer, Kyle and Odent, Sylvie and Katsanis, Nicholas and B{\'e}zieau, St{\'e}phane and Koenig, Michel and Davis, Erica E and Pasquier, Laurent and K{\"u}ry, S{\'e}bastien} } @article {443, title = {Complex phenotypes associated with STIM1 mutations in both coiled coil and EF-hand domains.}, journal = {Neuromuscul Disord}, volume = {27}, year = {2017}, month = {2017 Sep}, pages = {861-872}, abstract = {

Dominant mutations in STIM1 are a cause of three allelic conditions: tubular aggregate myopathy, Stormorken syndrome (a complex phenotype including myopathy, hyposplenism, hypocalcaemia and bleeding diathesis), and a platelet dysfunction disorder, York platelet syndrome. Previous reports have suggested a genotype-phenotype correlation with mutations in the N-terminal EF-hand domain associated with tubular aggregate myopathy, and a common mutation at p.R304W in a coiled coil domain associated with Stormorken syndrome. In this study individuals with STIM1 variants were identified by exome sequencing or STIM1 direct sequencing, and assessed for neuromuscular, haematological and biochemical evidence of the allelic disorders of STIM1. STIM1 mutations were investigated by fibroblast calcium imaging and 3D modelling. Six individuals with STIM1 mutations, including two novel mutations (c.262A>G (p.S88G) and c.911G>A (p.R304Q)), were identified. Extra-neuromuscular symptoms including thrombocytopenia, platelet dysfunction, hypocalcaemia or hyposplenism were present in 5/6 patients with mutations in both the EF-hand and CC domains. 3/6 patients had psychiatric disorders, not previously reported in STIM1 disease. Review of published STIM1 patients (n = 49) confirmed that neuromuscular symptoms are present in most patients. We conclude that the phenotype associated with activating STIM1 mutations frequently includes extra-neuromuscular features such as hypocalcaemia, hypo-/asplenia and platelet dysfunction regardless of mutation domain.

}, keywords = {Adult, Blood Platelet Disorders, Calcium, Cell Culture Techniques, DNA Mutational Analysis, Dyslexia, Erythrocytes, Abnormal, Family Health, Female, Fibroblasts, Genetic Association Studies, Humans, Ichthyosis, Magnetic Resonance Imaging, Male, Microscopy, Electron, Middle Aged, Migraine Disorders, Miosis, Models, Molecular, Muscle Fatigue, Muscle, Skeletal, Mutation, Myopathies, Structural, Congenital, NAD, Neoplasm Proteins, Spleen, Stromal Interaction Molecule 1}, issn = {1873-2364}, doi = {10.1016/j.nmd.2017.05.002}, author = {Harris, Elizabeth and Burki, Umar and Marini-Bettolo, Chiara and Neri, Marcella and Scotton, Chiara and Hudson, Judith and Bertoli, Marta and Evangelista, Teresinha and Vroling, Bas and Polvikoski, Tuomo and Roberts, Mark and Topf, Ana and Bushby, Kate and McArthur, Daniel and Lochm{\"u}ller, Hanns and Ferlini, Alessandra and Straub, Volker and Barresi, Rita} } @article {336, title = {Multilevel analyses of SCN5A mutations in arrhythmogenic right ventricular dysplasia/cardiomyopathy suggest non-canonical mechanisms for disease pathogenesis.}, journal = {Cardiovasc Res}, volume = {113}, year = {2017}, month = {2017 01}, pages = {102-111}, abstract = {

AIMS: Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy (ARVD/C) is often associated with desmosomal mutations. Recent studies suggest an interaction between the desmosome and sodium channel protein Na1.5. We aimed to determine the prevalence and biophysical properties of mutations in SCN5A (the gene encoding Na1.5) in ARVD/C.

METHODS AND RESULTS: We performed whole-exome sequencing in six ARVD/C patients (33\% male, 38.2 {\textpm} 12.1 years) without a desmosomal mutation. We found a rare missense variant (p.Arg1898His; R1898H) in SCN5A in one patient. We generated induced pluripotent stem cell-derived cardiomyocytes (hIPSC-CMs) from the patient{\textquoteright}s peripheral blood mononuclear cells. The variant was then corrected (R1898R) using Clustered Regularly Interspaced Short Palindromic Repeats/Cas9 technology, allowing us to study the impact of the R1898H substitution in the same cellular background. Whole-cell patch clamping revealed a 36\% reduction in peak sodium current (P = 0.002); super-resolution fluorescence microscopy showed reduced abundance of Na1.5 (P = 0.005) and N-Cadherin (P = 0.026) clusters at the intercalated disc. Subsequently, we sequenced SCN5A in an additional 281 ARVD/C patients (60\% male, 34.8 {\textpm} 13.7 years, 52\% desmosomal mutation-carriers). Five (1.8\%) subjects harboured a putatively pathogenic SCN5A variant (p.Tyr416Cys, p.Leu729del, p.Arg1623Ter, p.Ser1787Asn, and p.Val2016Met). SCN5A variants were associated with prolonged QRS duration (119 {\textpm} 15 vs. 94 {\textpm} 14 ms, P < 0.01) and all SCN5A variant carriers had major structural abnormalities on cardiac imaging.

CONCLUSIONS: Almost 2\% of ARVD/C patients harbour rare SCN5A variants. For one of these variants, we demonstrated reduced sodium current, Na1.5 and N-Cadherin clusters at junctional sites. This suggests that Na1.5 is in a functional complex with adhesion molecules, and reveals potential non-canonical mechanisms by which Na1.5 dysfunction causes cardiomyopathy.

}, keywords = {Adult, Antigens, CD, Arrhythmogenic Right Ventricular Dysplasia, Cadherins, Cell Differentiation, CRISPR-Cas Systems, DNA Mutational Analysis, Electrocardiography, Exome, Female, Gene Editing, Gene Frequency, Genetic Predisposition to Disease, Genome-Wide Association Study, HEK293 Cells, Humans, Induced Pluripotent Stem Cells, Magnetic Resonance Imaging, Male, Membrane Potentials, Middle Aged, Multilevel Analysis, Mutation, Missense, Myocytes, Cardiac, NAV1.5 Voltage-Gated Sodium Channel, Netherlands, Phenotype, Sodium, Transfection, United States, Young Adult}, issn = {1755-3245}, doi = {10.1093/cvr/cvw234}, author = {Te Riele, Anneline S J M and Agullo-Pascual, Esperanza and James, Cynthia A and Leo-Macias, Alejandra and Cerrone, Marina and Zhang, Mingliang and Lin, Xianming and Lin, Bin and Sobreira, Nara L and Amat-Alarcon, Nuria and Marsman, Roos F and Murray, Brittney and Tichnell, Crystal and van der Heijden, Jeroen F and Dooijes, Dennis and van Veen, Toon A B and Tandri, Harikrishna and Fowler, Steven J and Hauer, Richard N W and Tomaselli, Gordon and van den Berg, Maarten P and Taylor, Matthew R G and Brun, Francesca and Sinagra, Gianfranco and Wilde, Arthur A M and Mestroni, Luisa and Bezzina, Connie R and Calkins, Hugh and Peter van Tintelen, J and Bu, Lei and Delmar, Mario and Judge, Daniel P} } @article {334, title = {A Recurrent De Novo Variant in NACC1 Causes a Syndrome Characterized by Infantile Epilepsy, Cataracts, and Profound Developmental Delay.}, journal = {Am J Hum Genet}, volume = {100}, year = {2017}, month = {2017 Feb 02}, pages = {343-351}, abstract = {

Whole-exome sequencing (WES) has increasingly enabled new pathogenic gene variant identification for undiagnosed neurodevelopmental disorders and provided insights into both gene function and disease biology. Here, we describe seven children with a neurodevelopmental disorder characterized by microcephaly, profound developmental delays and/or intellectual disability, cataracts, severe epilepsy including infantile spasms, irritability, failure to thrive, and stereotypic hand movements. Brain imaging in these individuals reveals delay in myelination and cerebral atrophy. We observe an identical recurrent de novo heterozygous c.892C>T (p.Arg298Trp) variant in the nucleus accumbens associated 1 (NACC1) gene in seven affected individuals. One of the seven individuals is mosaic for this variant. NACC1 encodes a transcriptional repressor implicated in gene expression and has not previously been associated with germline disorders. The probability of finding the same missense NACC1 variant by chance in 7 out of 17,228 individuals who~underwent WES for diagnoses of neurodevelopmental phenotypes is extremely small and achieves genome-wide significance (p~= 1.25~{\texttimes} 10). Selective constraint against missense variants in NACC1 makes this excess of an identical missense variant in all seven individuals more remarkable. Our findings are consistent with a germline recurrent mutational hotspot associated with an allele-specific neurodevelopmental phenotype in NACC1.

}, keywords = {Alleles, Amino Acid Sequence, Brain, Cataract, Child, Child, Preschool, Female, Genetic Variation, Genome-Wide Association Study, Humans, Infant, Intellectual Disability, Magnetic Resonance Imaging, Male, Microcephaly, Mutation, Missense, Neoplasm Proteins, Pedigree, Phenotype, Repressor Proteins, Spasms, Infantile}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2016.12.013}, author = {Schoch, Kelly and Meng, Linyan and Szelinger, Szabolcs and Bearden, David R and Stray-Pedersen, Asbjorg and Busk, Oyvind L and Stong, Nicholas and Liston, Eriskay and Cohn, Ronald D and Scaglia, Fernando and Rosenfeld, Jill A and Tarpinian, Jennifer and Skraban, Cara M and Deardorff, Matthew A and Friedman, Jeremy N and Akdemir, Zeynep Coban and Walley, Nicole and Mikati, Mohamad A and Kranz, Peter G and Jasien, Joan and McConkie-Rosell, Allyn and McDonald, Marie and Wechsler, Stephanie Burns and Freemark, Michael and Kansagra, Sujay and Freedman, Sharon and Bali, Deeksha and Millan, Francisca and Bale, Sherri and Nelson, Stanley F and Lee, Hane and Dorrani, Naghmeh and Goldstein, David B and Xiao, Rui and Yang, Yaping and Posey, Jennifer E and Martinez-Agosto, Julian A and Lupski, James R and Wangler, Michael F and Shashi, Vandana} } @article {75, title = {Monoallelic and Biallelic Variants in EMC1 Identified in Individuals with Global Developmental Delay, Hypotonia, Scoliosis, and Cerebellar Atrophy.}, journal = {Am J Hum Genet}, volume = {98}, year = {2016}, month = {2016 Mar 03}, pages = {562-570}, abstract = {

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

}, keywords = {Adolescent, Alleles, Amino Acid Sequence, Atrophy, Cerebellum, Child, Child, Preschool, Developmental Disabilities, Endoplasmic Reticulum-Associated Degradation, Female, Genetic Association Studies, Genetic Variation, Heterozygote, Humans, Magnetic Resonance Imaging, Male, Molecular Sequence Data, Muscle Hypotonia, Mutation, Pedigree, Protein Folding, Proteins, Scoliosis}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2016.01.011}, author = {Harel, Tamar and Yesil, G{\"o}zde and Bayram, Yavuz and Coban-Akdemir, Zeynep and Charng, Wu-Lin and Karaca, Ender and Al Asmari, Ali and Eldomery, Mohammad K and Hunter, Jill V and Jhangiani, Shalini N and Rosenfeld, Jill A and Pehlivan, Davut and El-Hattab, Ayman W and Saleh, Mohammed A and LeDuc, Charles A and Muzny, Donna and Boerwinkle, Eric and Gibbs, Richard A and Chung, Wendy K and Yang, Yaping and Belmont, John W and Lupski, James R} } @article {70, title = {Recessive Inactivating Mutations in TBCK, Encoding a Rab GTPase-Activating Protein, Cause Severe Infantile Syndromic Encephalopathy.}, journal = {Am J Hum Genet}, volume = {98}, year = {2016}, month = {2016 Apr 07}, pages = {772-81}, abstract = {

Infantile encephalopathies are a group of clinically and biologically heterogeneous disorders for which the genetic basis remains largely unknown. Here, we report a syndromic neonatal encephalopathy characterized by profound developmental disability, severe hypotonia, seizures, diminished respiratory drive requiring mechanical ventilation, brain atrophy, dysgenesis of the corpus callosum, cerebellar vermis hypoplasia, and facial dysmorphism. Biallelic inactivating mutations in TBCK (TBC1-domain-containing kinase) were independently identified by whole-exome sequencing as the cause of this condition in four unrelated families. Matching these families was facilitated by the sharing of phenotypic profiles and WES data in a recently released web-based tool (Geno2MP) that links phenotypic information to rare variants in families with Mendelian traits. TBCK is a putative GTPase-activating protein (GAP) for small GTPases of the Rab family and has been shown to control cell growth and proliferation, actin-cytoskeleton dynamics, and mTOR signaling. Two of the three mutations (c.376C>T [p.Arg126(*)] and c.1363A>T [p.Lys455(*)]) are predicted to truncate the protein, and loss of the major TBCK isoform was confirmed in primary fibroblasts from one affected individual. The third mutation, c.1532G>A (p.Arg511His), alters a conserved residue within the TBC1 domain. Structural analysis implicated Arg511 as a required residue for Rab-GAP function, and in~silico homology modeling predicted impaired GAP function in the corresponding mutant. These results suggest that loss of Rab-GAP activity is the underlying mechanism of disease. In contrast to other disorders caused by dysregulated mTOR signaling associated with focal or global brain overgrowth, impaired TBCK function results in progressive loss of brain volume.

}, keywords = {Adolescent, Alleles, Amino Acid Sequence, Brain Diseases, Child, Child, Preschool, Corpus Callosum, Female, GTPase-Activating Proteins, Humans, Magnetic Resonance Imaging, Male, Molecular Sequence Data, Mutation, Pedigree, Protein Conformation, Protein-Serine-Threonine Kinases, Signal Transduction, TOR Serine-Threonine Kinases}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2016.01.016}, author = {Chong, Jessica X and Caputo, Viviana and Phelps, Ian G and Stella, Lorenzo and Worgan, Lisa and Dempsey, Jennifer C and Nguyen, Alina and Leuzzi, Vincenzo and Webster, Richard and Pizzuti, Antonio and Marvin, Colby T and Ishak, Gisele E and Ardern-Holmes, Simone and Richmond, Zara and Bamshad, Michael J and Ortiz-Gonzalez, Xilma R and Tartaglia, Marco and Chopra, Maya and Doherty, Dan} } @article {29, title = {Somatic mosaicism for a lethal TRPV4 mutation results in non-lethal metatropic dysplasia.}, journal = {Am J Med Genet A}, volume = {170}, year = {2016}, month = {2016 Dec}, pages = {3298-3302}, abstract = {

Dominant mutations in TRPV4, which encodes the Transient Receptor Potential Cation Channel Subfamily V Member 4 calcium channel, result in a series of musculoskeletal disorders that include a set of peripheral neuropathies and a broad phenotypic spectrum of skeletal dysplasias. The skeletal phenotypes range from brachyolmia, in which there is scoliosis with mild short stature, through perinatal lethal metatropic dysplasia. We describe a case with phenotypic findings consistent with metatropic dysplasia, but in whom no TRPV4 mutation was detected by Sanger sequence analysis. Exome sequence analysis identified a known lethal metatropic dysplasia mutation, TRPV4 , which was present at lower frequency than would be expected for a heterozygous change. The affected individual was shown to be a somatic mosaic for the mutation, providing an explanation for the milder than expected phenotype. The data illustrate that high-throughput sequencing of genomic DNA can facilitate detection of mosaicism with higher sensitivity than Sanger sequence analysis and identify a new genetic mechanism for metatropic dysplasia. {\textcopyright} 2016 Wiley Periodicals, Inc.

}, keywords = {Alleles, DNA Mutational Analysis, Dwarfism, Exons, Genetic Association Studies, Humans, Infant, Magnetic Resonance Imaging, Mosaicism, Mutation, Osteochondrodysplasias, Phenotype, Physical Examination, Radiography, TRPV Cation Channels}, issn = {1552-4833}, doi = {10.1002/ajmg.a.37942}, author = {Weinstein, Michael M and Kang, Taekyu and Lachman, Ralph S and Bamshad, Michael and Nickerson, Deborah A and Krakow, Deborah and Cohn, Daniel H} } @article {181, title = {Exome sequencing identifies a homozygous C5orf42 variant in a Turkish kindred with oral-facial-digital syndrome type VI.}, journal = {Am J Med Genet A}, volume = {167A}, year = {2015}, month = {2015 Sep}, pages = {2132-7}, abstract = {

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

}, keywords = {Abnormalities, Multiple, Cerebellar Diseases, Cerebellum, Child, Cleft Palate, Exome, Eye Abnormalities, Female, Genetic Predisposition to Disease, Hamartoma, Homozygote, Humans, Kidney Diseases, Cystic, Magnetic Resonance Imaging, Male, Membrane Proteins, Middle Aged, Mutation, Orofaciodigital Syndromes, Phenotype, Retina, Turkey}, issn = {1552-4833}, doi = {10.1002/ajmg.a.37092}, author = {Bayram, Yavuz and Aydin, Hatip and Gambin, Tomasz and Akdemir, Zeynep Coban and Atik, Mehmed M and Karaca, Ender and Karaman, Ali and Pehlivan, Davut and Jhangiani, Shalini N and Gibbs, Richard A and Lupski, James R} } @article {154, title = {KIAA0586 is Mutated in Joubert Syndrome.}, journal = {Hum Mutat}, volume = {36}, year = {2015}, month = {2015 Sep}, pages = {831-5}, abstract = {

Joubert syndrome (JS) is a recessive neurodevelopmental disorder characterized by a distinctive mid-hindbrain malformation. JS is part of a group of disorders called ciliopathies based on their overlapping phenotypes and common underlying pathophysiology linked to primary cilium dysfunction. Biallelic mutations in one of 28 genes, all encoding proteins localizing to the primary cilium or basal body, can cause JS. Despite this large number of genes, the genetic cause can currently be determined in about 62\% of individuals with JS. To identify novel JS genes, we performed whole exome sequencing on 35 individuals with JS and found biallelic rare deleterious variants (RDVs) in KIAA0586, encoding a centrosomal protein required for ciliogenesis, in one individual. Targeted next-generation sequencing in a large JS cohort identified biallelic RDVs in eight additional families for an estimated prevalence of 2.5\% (9/366 JS families). All affected individuals displayed JS phenotypes toward the mild end of the spectrum.

}, keywords = {Abnormalities, Multiple, Adolescent, Adult, Alternative Splicing, Brain, Cell Cycle Proteins, Cerebellum, Child, Child, Preschool, DNA Mutational Analysis, Eye Abnormalities, Gene Order, Genetic Association Studies, Humans, Kidney Diseases, Cystic, Magnetic Resonance Imaging, Mutation, Phenotype, Retina, Young Adult}, issn = {1098-1004}, doi = {10.1002/humu.22821}, author = {Bachmann-Gagescu, Ruxandra and Phelps, Ian G and Dempsey, Jennifer C and Sharma, Vivek A and Ishak, Gisele E and Boyle, Evan A and Wilson, Meredith and Marques Louren{\c c}o, Charles and Arslan, Mutluay and Shendure, Jay and Doherty, Dan} } @article {214, title = {Truncating mutations in the last exon of NOTCH3 cause lateral meningocele syndrome.}, journal = {Am J Med Genet A}, volume = {167A}, year = {2015}, month = {2015 Feb}, pages = {271-81}, abstract = {

Lateral meningocele syndrome (LMS, OMIM\%130720), also known as Lehman syndrome, is a very rare skeletal disorder with facial anomalies, hypotonia and meningocele-related neurologic dysfunction. The characteristic lateral meningoceles represent the severe end of the dural ectasia spectrum and are typically most severe in the lower spine. Facial features of LMS include hypertelorism and telecanthus, high arched eyebrows, ptosis, midfacial hypoplasia, micrognathia, high and narrow palate, low-set ears and a hypotonic appearance. Hyperextensibility, hernias and scoliosis reflect a connective tissue abnormality, and aortic dilation, a high-pitched nasal voice, wormian bones and osteolysis may be present. Lateral meningocele syndrome has phenotypic overlap with Hajdu-Cheney syndrome. We performed exome resequencing in five unrelated individuals with LMS and identified heterozygous truncating NOTCH3 mutations. In an additional unrelated individual Sanger sequencing revealed a deleterious variant in the same exon 33. In total, five novel de novo NOTCH3 mutations were identified in six unrelated patients. One had a 26 bp deletion (c.6461_6486del, p.G2154fsTer78), two carried the same single base pair insertion (c.6692_93insC, p.P2231fsTer11), and three individuals had a nonsense point mutation at c.6247A > T (pK2083*), c.6663C > G (p.Y2221*) or c.6732C > A, (p.Y2244*). All mutations cluster into the last coding exon, resulting in premature termination of the protein and truncation of the negative regulatory proline-glutamate-serine-threonine rich PEST domain. Our results suggest that mutant mRNA products escape nonsense mediated decay. The truncated NOTCH3 may cause gain-of-function through decreased clearance of the active intracellular product, resembling NOTCH2 mutations in the clinically related Hajdu-Cheney syndrome and contrasting the NOTCH3 missense mutations causing CADASIL.

}, keywords = {Abnormalities, Multiple, Child, Child, Preschool, DNA Mutational Analysis, Exome, Exons, Facies, High-Throughput Nucleotide Sequencing, Humans, Magnetic Resonance Imaging, Male, Meningocele, Mutation, Phenotype, Receptor, Notch3, Receptors, Notch, Young Adult}, issn = {1552-4833}, doi = {10.1002/ajmg.a.36863}, author = {Gripp, Karen W and Robbins, Katherine M and Sobreira, Nara L and Witmer, P Dane and Bird, Lynne M and Avela, Kristiina and M{\"a}kitie, Outi and Alves, Daniela and Hogue, Jacob S and Zackai, Elaine H and Doheny, Kimberly F and Stabley, Deborah L and Sol-Church, Katia} } @article {226, title = {Somatic mutations in cerebral cortical malformations.}, journal = {N Engl J Med}, volume = {371}, year = {2014}, month = {2014 Aug 21}, pages = {733-43}, abstract = {

BACKGROUND: Although there is increasing recognition of the role of somatic mutations in genetic disorders, the prevalence of somatic mutations in neurodevelopmental disease and the optimal techniques to detect somatic mosaicism have not been systematically evaluated.

METHODS: Using a customized panel of known and candidate genes associated with brain malformations, we applied targeted high-coverage sequencing (depth, >=200{\texttimes}) to leukocyte-derived DNA samples from 158 persons with brain malformations, including the double-cortex syndrome (subcortical band heterotopia, 30 persons), polymicrogyria with megalencephaly (20), periventricular nodular heterotopia (61), and pachygyria (47). We validated candidate mutations with the use of Sanger sequencing and, for variants present at unequal read depths, subcloning followed by colony sequencing.

RESULTS: Validated, causal mutations were found in 27 persons (17\%; range, 10 to 30\% for each phenotype). Mutations were somatic in 8 of the 27 (30\%), predominantly in persons with the double-cortex syndrome (in whom we found mutations in DCX and LIS1), persons with periventricular nodular heterotopia (FLNA), and persons with pachygyria (TUBB2B). Of the somatic mutations we detected, 5 (63\%) were undetectable with the use of traditional Sanger sequencing but were validated through subcloning and subsequent sequencing of the subcloned DNA. We found potentially causal mutations in the candidate genes DYNC1H1, KIF5C, and other kinesin genes in persons with pachygyria.

CONCLUSIONS: Targeted sequencing was found to be useful for detecting somatic mutations in patients with brain malformations. High-coverage sequencing panels provide an important complement to whole-exome and whole-genome sequencing in the evaluation of somatic mutations in neuropsychiatric disease. (Funded by the National Institute of Neurological Disorders and Stroke and others.).

}, keywords = {Cerebral Cortex, Classical Lissencephalies and Subcortical Band Heterotopias, DNA Mutational Analysis, Humans, Lissencephaly, Magnetic Resonance Imaging, Malformations of Cortical Development, Mutation, Periventricular Nodular Heterotopia}, issn = {1533-4406}, doi = {10.1056/NEJMoa1314432}, author = {Jamuar, Saumya S and Lam, Anh-Thu N and Kircher, Martin and D{\textquoteright}Gama, Alissa M and Wang, Jian and Barry, Brenda J and Zhang, Xiaochang and Hill, Robert Sean and Partlow, Jennifer N and Rozzo, Aldo and Servattalab, Sarah and Mehta, Bhaven K and Topcu, Meral and Amrom, Dina and Andermann, Eva and Dan, Bernard and Parrini, Elena and Guerrini, Renzo and Scheffer, Ingrid E and Berkovic, Samuel F and Leventer, Richard J and Shen, Yiping and Wu, Bai Lin and Barkovich, A James and Sahin, Mustafa and Chang, Bernard S and Bamshad, Michael and Nickerson, Deborah A and Shendure, Jay and Poduri, Annapurna and Yu, Timothy W and Walsh, Christopher A} } @article {287, title = {Mutations in VRK1 associated with complex motor and sensory axonal neuropathy plus microcephaly.}, journal = {JAMA Neurol}, volume = {70}, year = {2013}, month = {2013 Dec}, pages = {1491-8}, abstract = {

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

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

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

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

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

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

}, keywords = {Child, Child, Preschool, DNA Mutational Analysis, Female, Genotype, Hereditary Sensory and Motor Neuropathy, Humans, Infant, Intracellular Signaling Peptides and Proteins, Magnetic Resonance Imaging, Male, Microcephaly, Mutation, Neural Conduction, Polymorphism, Single Nucleotide, Protein-Serine-Threonine Kinases}, issn = {2168-6157}, doi = {10.1001/jamaneurol.2013.4598}, author = {Gonzaga-Jauregui, Claudia and Lotze, Timothy and Jamal, Leila and Penney, Samantha and Campbell, Ian M and Pehlivan, Davut and Hunter, Jill V and Woodbury, Suzanne L and Raymond, Gerald and Adesina, Adekunle M and Jhangiani, Shalini N and Reid, Jeffrey G and Muzny, Donna M and Boerwinkle, Eric and Lupski, James R and Gibbs, Richard A and Wiszniewski, Wojciech} } @article {297, title = {TM4SF20 ancestral deletion and susceptibility to a pediatric disorder of early language delay and cerebral white matter hyperintensities.}, journal = {Am J Hum Genet}, volume = {93}, year = {2013}, month = {2013 Aug 08}, pages = {197-210}, abstract = {

White matter hyperintensities (WMHs) of the brain are important markers of aging and small-vessel disease. WMHs are rare in healthy children and, when observed, often occur with comorbid neuroinflammatory or vasculitic processes. Here, we describe a complex 4 kb deletion in 2q36.3 that segregates with early childhood communication disorders and WMH in 15 unrelated families predominantly from Southeast Asia. The premature brain aging phenotype with punctate and multifocal WMHs was observed in ~70\% of young carrier parents who underwent brain MRI. The complex deletion removes the penultimate exon 3 of TM4SF20, a gene encoding a transmembrane protein of unknown function. Minigene analysis showed that the resultant net loss of an exon introduces a premature stop codon, which, in turn, leads to the generation of a stable protein that fails to target to the plasma membrane and accumulates in the cytoplasm. Finally, we report this deletion to be enriched in individuals of Vietnamese Kinh descent, with an allele frequency of about 1\%, embedded in an ancestral haplotype. Our data point to a constellation of early language delay and WMH phenotypes, driven by a likely toxic mechanism of TM4SF20 truncation, and highlight the importance of understanding and managing population-specific low-frequency pathogenic alleles.

}, keywords = {Age of Onset, Aging, Premature, Asian Continental Ancestry Group, Base Sequence, Brain, Child, Child, Preschool, Chromosomes, Human, Pair 2, Exons, Female, Genetic Predisposition to Disease, Humans, Language Development Disorders, Leukoencephalopathies, Magnetic Resonance Imaging, Male, Molecular Sequence Data, Pedigree, Sequence Analysis, DNA, Sequence Deletion, Tetraspanins}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2013.05.027}, author = {Wiszniewski, Wojciech and Hunter, Jill V and Hanchard, Neil A and Willer, Jason R and Shaw, Chad and Tian, Qi and Illner, Anna and Wang, Xueqing and Cheung, Sau W and Patel, Ankita and Campbell, Ian M and Gelowani, Violet and Hixson, Patricia and Ester, Audrey R and Azamian, Mahshid S and Potocki, Lorraine and Zapata, Gladys and Hernandez, Patricia P and Ramocki, Melissa B and Santos-Cortez, Regie L P and Wang, Gao and York, Michele K and Justice, Monica J and Chu, Zili D and Bader, Patricia I and Omo-Griffith, Lisa and Madduri, Nirupama S and Scharer, Gunter and Crawford, Heather P and Yanatatsaneejit, Pattamawadee and Eifert, Anna and Kerr, Jeffery and Bacino, Carlos A and Franklin, Adiaha I A and Goin-Kochel, Robin P and Simpson, Gayle and Immken, LaDonna and Haque, Muhammad E and Stosic, Marija and Williams, Misti D and Morgan, Thomas M and Pruthi, Sumit and Omary, Reed and Boyadjiev, Simeon A and Win, Kay K and Thida, Aye and Hurles, Matthew and Hibberd, Martin Lloyd and Khor, Chiea Chuen and Van Vinh Chau, Nguyen and Gallagher, Thomas E and Mutirangura, Apiwat and Stankiewicz, Pawel and Beaudet, Arthur L and Maletic-Savatic, Mirjana and Rosenfeld, Jill A and Shaffer, Lisa G and Davis, Erica E and Belmont, John W and Dunstan, Sarah and Simmons, Cameron P and Bonnen, Penelope E and Leal, Suzanne M and Katsanis, Nicholas and Lupski, James R and Lalani, Seema R} }