@article {1000,
	title = {A DNA repair disorder caused by de novo monoallelic DDB1 variants is associated with a neurodevelopmental syndrome.},
	journal = {Am J Hum Genet},
	volume = {108},
	year = {2021},
	month = {2021 04 01},
	pages = {749-756},
	abstract = {<p>The DNA damage-binding protein 1 (DDB1) is part of the CUL4-DDB1 ubiquitin E3 ligase complex (CRL4), which is essential for DNA repair, chromatin remodeling, DNA replication, and signal transduction. Loss-of-function variants in genes encoding the complex components CUL4 and PHIP have been reported to cause syndromic intellectual disability with hypotonia and obesity, but no phenotype has been reported in association with DDB1 variants. Here, we report eight unrelated individuals, identified through Matchmaker Exchange, with de novo monoallelic variants in DDB1, including one recurrent variant in four individuals. The affected individuals have a consistent phenotype of hypotonia, mild to moderate intellectual disability, and similar facies, including horizontal or slightly bowed eyebrows, deep-set eyes, full cheeks, a short nose, and large, fleshy and forward-facing earlobes, demonstrated in the composite face generated from the cohort. Digital anomalies, including brachydactyly and syndactyly, were common. Three older individuals have obesity. We show that cells derived from affected individuals have altered DDB1 function resulting in abnormal DNA damage signatures and histone methylation following UV-induced DNA damage. Overall, our study adds to the growing family of neurodevelopmental phenotypes mediated by disruption of the CRL4 ubiquitin ligase pathway and begins to delineate the phenotypic and molecular effects of DDB1 misregulation.</p>},
	keywords = {Adolescent, Alleles, Child, Child, Preschool, DNA Repair, DNA-Binding Proteins, Female, Humans, Male, Mutation, Neurodevelopmental Disorders, Phenotype, Syndrome},
	issn = {1537-6605},
	doi = {10.1016/j.ajhg.2021.03.007},
	author = {White, Susan M and Bhoj, Elizabeth and Nellaker, Christoffer and Lachmeijer, Augusta M A and Marshall, Aren E and Boycott, Kym M and Li, Dong and Smith, Wendy and Hartley, Taila and McBride, Arran and Ernst, Michelle E and May, Alison S and Wieczorek, Dagmar and Abou Jamra, Rami and Koch-Hogrebe, Margarete and {\~O}unap, Katrin and Pajusalu, Sander and van Gassen, K L I and Sadedin, Simon and Ellingwood, Sara and Tan, Tiong Yang and Christodoulou, John and Barea, Jaime and Lockhart, Paul J and Nezarati, Marjan M and Kernohan, Kristin D}
}
@article {753,
	title = {Recurrent arginine substitutions in the ACTG2 gene are the primary driver of disease burden and severity in visceral myopathy.},
	journal = {Hum Mutat},
	volume = {41},
	year = {2020},
	month = {2020 03},
	pages = {641-654},
	abstract = {<p>Visceral myopathy with abnormal intestinal and bladder peristalsis includes a clinical spectrum with megacystis-microcolon intestinal hypoperistalsis syndrome and chronic intestinal pseudo-obstruction. The vast majority of cases are caused by dominant variants in ACTG2; however, the overall genetic architecture of visceral myopathy has not been well-characterized. We ascertained 53 families, with visceral myopathy based on megacystis, functional bladder/gastrointestinal obstruction, or microcolon. A combination of targeted ACTG2 sequencing and exome sequencing was used. We report a molecular diagnostic rate of 64\% (34/53), of which 97\% (33/34) is attributed to ACTG2. Strikingly, missense mutations in five conserved arginine residues involving CpG dinucleotides accounted for 49\% (26/53) of disease in the cohort. As a group, the ACTG2-negative cases had a more favorable clinical outcome and more restricted disease. Within the ACTG2-positive group, poor outcomes (characterized by total parenteral nutrition dependence, death, or transplantation) were invariably due to one of the arginine missense alleles. Analysis of specific residues suggests a severity spectrum of p.Arg178>p.Arg257>p.Arg40 along with other less-frequently reported sites p.Arg63 and p.Arg211. These results provide genotype-phenotype correlation for ACTG2-related disease and demonstrate the importance of arginine missense changes in visceral myopathy.</p>},
	issn = {1098-1004},
	doi = {10.1002/humu.23960},
	author = {Assia Batzir, Nurit and Kishor Bhagwat, Pranjali and Larson, Austin and Coban Akdemir, Zeynep and Bag{\l}aj, Maciej and Bofferding, Leon and Bosanko, Katherine B and Bouassida, Skander and Callewaert, Bert and Cannon, Ashley and Enchautegui Colon, Yazmin and Garnica, Adolfo D and Harr, Margaret H and Heck, Sandra and Hurst, Anna C E and Jhangiani, Shalini N and Isidor, Bertrand and Littlejohn, Rebecca O and Liu, Pengfei and Magoulas, Pilar and Mar Fan, Helen and Marom, Ronit and McLean, Scott and Nezarati, Marjan M and Nugent, Kimberly M and Petersen, Michael B and Rocha, Maria L and Roeder, Elizabeth and Smigiel, Robert and Tully, Ian and Weisfeld-Adams, James and Wells, Katerina O and Posey, Jennifer E and Lupski, James R and Beaudet, Arthur L and Wangler, Michael F}
}
