@article {1012, title = {Pathogenic variants in , a chromatin remodeler, cause a range of syndromic neurodevelopmental features.}, journal = {Sci Adv}, volume = {7}, year = {2021}, month = {2021 May}, abstract = {

Intellectual disability encompasses a wide spectrum of neurodevelopmental disorders, with many linked genetic loci. However, the underlying molecular mechanism for more than 50\% of the patients remains elusive. We describe pathogenic variants in , encoding the ATPase motor of the ISWI chromatin remodeler, as a cause of a previously unidentified neurodevelopmental disorder, identifying 12 individuals with de novo or dominantly segregating rare heterozygous variants. Accompanying phenotypes include mild developmental delay, frequent postnatal short stature and microcephaly, and recurrent dysmorphic features. Loss of function of the SMARCA5 ortholog led to smaller body size, reduced sensory dendrite complexity, and tiling defects in larvae. In adult flies, Iswi neural knockdown caused decreased brain size, aberrant mushroom body morphology, and abnormal locomotor function. loss of function was rescued by wild-type but not mutant SMARCA5. Our results demonstrate that pathogenic variants cause a neurodevelopmental syndrome with mild facial dysmorphia.

}, issn = {2375-2548}, doi = {10.1126/sciadv.abf2066}, author = {Li, Dong and Wang, Qin and Gong, Naihua N and Kurolap, Alina and Feldman, Hagit Baris and Boy, Nikolas and Brugger, Melanie and Grand, Katheryn and McWalter, Kirsty and Guillen Sacoto, Maria J and Wakeling, Emma and Hurst, Jane and March, Michael E and Bhoj, Elizabeth J and Nowaczyk, Ma{\l}gorzata J M and Gonzaga-Jauregui, Claudia and Mathew, Mariam and Dava-Wala, Ashita and Siemon, Amy and Bartholomew, Dennis and Huang, Yue and Lee, Hane and Martinez-Agosto, Julian A and Schwaibold, Eva M C and Brunet, Theresa and Choukair, Daniela and Pais, Lynn S and White, Susan M and Christodoulou, John and Brown, Dana and Lindstrom, Kristin and Grebe, Theresa and Tiosano, Dov and Kayser, Matthew S and Tan, Tiong Yang and Deardorff, Matthew A and Song, Yuanquan and Hakonarson, Hakon} } @article {637, title = {Clinically severe CACNA1A alleles affect synaptic function and neurodegeneration differentially.}, journal = {PLoS Genet}, volume = {13}, year = {2017}, month = {2017 Jul}, pages = {e1006905}, abstract = {

Dominant mutations in CACNA1A, encoding the α-1A subunit of the neuronal P/Q type voltage-dependent Ca2+ channel, can cause diverse neurological phenotypes. Rare cases of markedly severe early onset developmental delay and congenital ataxia can be due to de novo CACNA1A missense alleles, with variants affecting the S4 transmembrane segments of the channel, some of which are reported to be loss-of-function. Exome sequencing in five individuals with severe early onset ataxia identified one novel variant (p.R1673P), in a girl with global developmental delay and progressive cerebellar atrophy, and a recurrent, de novo p.R1664Q variant, in four individuals with global developmental delay, hypotonia, and ophthalmologic abnormalities. Given the severity of these phenotypes we explored their functional impact in Drosophila. We previously generated null and partial loss-of-function alleles of cac, the homolog of CACNA1A in Drosophila. Here, we created transgenic wild type and mutant genomic rescue constructs with the two noted conserved point mutations. The p.R1673P mutant failed to rescue cac lethality, displayed a gain-of-function phenotype in electroretinograms (ERG) recorded from mutant clones, and evolved a neurodegenerative phenotype in aging flies, based on ERGs and transmission electron microscopy. In contrast, the p.R1664Q variant exhibited loss of function and failed to develop a neurodegenerative phenotype. Hence, the novel R1673P allele produces neurodegenerative phenotypes in flies and human, likely due to a toxic gain of function.

}, keywords = {Alleles, Animals, Animals, Genetically Modified, Calcium Channels, Cerebellar Ataxia, Child, Child, Preschool, Drosophila melanogaster, Female, Genome, Human, Genome-Wide Association Study, Humans, Male, Microscopy, Electron, Transmission, Mutation, Missense, Neurodegenerative Diseases, Neuroimaging, Phenotype, Point Mutation}, issn = {1553-7404}, doi = {10.1371/journal.pgen.1006905}, author = {Luo, Xi and Rosenfeld, Jill A and Yamamoto, Shinya and Harel, Tamar and Zuo, Zhongyuan and Hall, Melissa and Wierenga, Klaas J and Pastore, Matthew T and Bartholomew, Dennis and Delgado, Mauricio R and Rotenberg, Joshua and Lewis, Richard Alan and Emrick, Lisa and Bacino, Carlos A and Eldomery, Mohammad K and Coban Akdemir, Zeynep and Xia, Fan and Yang, Yaping and Lalani, Seema R and Lotze, Timothy and Lupski, James R and Lee, Brendan and Bellen, Hugo J and Wangler, Michael F} } @article {211, title = {Mutations in PURA cause profound neonatal hypotonia, seizures, and encephalopathy in 5q31.3 microdeletion syndrome.}, journal = {Am J Hum Genet}, volume = {95}, year = {2014}, month = {2014 Nov 06}, pages = {579-83}, abstract = {

5q31.3 microdeletion syndrome is characterized by neonatal hypotonia, encephalopathy with or without epilepsy, and severe developmental delay, and the minimal critical deletion interval harbors three genes. We describe 11 individuals with clinical features of 5q31.3 microdeletion syndrome and de novo mutations in PURA, encoding transcriptional activator protein Pur-α, within the critical region. These data implicate causative PURA mutations responsible for the severe neurological phenotypes observed in this syndrome.

}, keywords = {Abnormalities, Multiple, Amino Acid Sequence, Animals, Base Sequence, Caenorhabditis elegans, Chromosome Deletion, Chromosome Mapping, Chromosomes, Human, Pair 5, DNA-Binding Proteins, Humans, Molecular Sequence Data, Muscle Hypotonia, Mutation, Seizures, Sequence Analysis, DNA, Syndrome, Transcription Factors}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2014.09.014}, author = {Lalani, Seema R and Zhang, Jing and Schaaf, Christian P and Brown, Chester W and Magoulas, Pilar and Tsai, Anne Chun-Hui and El-Gharbawy, Areeg and Wierenga, Klaas J and Bartholomew, Dennis and Fong, Chin-To and Barbaro-Dieber, Tina and Kukolich, Mary K and Burrage, Lindsay C and Austin, Elise and Keller, Kory and Pastore, Matthew and Fernandez, Fabio and Lotze, Timothy and Wilfong, Angus and Purcarin, Gabriela and Zhu, Wenmiao and Craigen, William J and McGuire, Marianne and Jain, Mahim and Cooney, Erin and Azamian, Mahshid and Bainbridge, Matthew N and Muzny, Donna M and Boerwinkle, Eric and Person, Richard E and Niu, Zhiyv and Eng, Christine M and Lupski, James R and Gibbs, Richard A and Beaudet, Arthur L and Yang, Yaping and Wang, Meng C and Xia, Fan} }