Publications by authors named "Allison D Britt"

2 Publications

  • Page 1 of 1

Genotypic and phenotypic variability of 22q11.2 microduplications: An institutional experience.

Am J Med Genet A 2019 11 3;179(11):2178-2189. Epub 2019 Sep 3.

Department of Pathology, University of Texas Medical Branch, Galveston, Texas.

Duplications in the 22q11.2 region can cause 22q11.2 duplication syndrome and encompass a variety of phenotypes including developmental delays, facial abnormalities, cardiovascular defects, central nervous system delays, and other congenital abnormalities. However, the contribution of these contiguous duplicated regions to the clinical phenotypes has not been fully elucidated. In this study, we identified nine patients carrying different 22q11.2 microduplications detected by chromosomal microarray. Of these patients, seven pediatric patients presented with various clinical features including two neonate cases died shortly after birth, and two healthy adults. We examined region specific genotype-phenotype associations and found unpredictability associated with 22q11.2 duplications in these nine patients.
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http://dx.doi.org/10.1002/ajmg.a.61345DOI Listing
November 2019

A De novo HDAC2 variant in a patient with features consistent with Cornelia de Lange syndrome phenotype.

Am J Med Genet A 2019 05 25;179(5):852-856. Epub 2019 Feb 25.

Department of Pediatrics, Division of Medical Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas.

Cornelia de Lange syndrome (CdLS) is an autosomal dominant genetic disorder caused by pathogenic variants in NIPBL, RAD21, SMC3, HDAC8, or SMC1A; all of which code for proteins that are components of, or interact with, the cohesin complex. Despite the identification of multiple genes associated with CdLS, over 25% of individuals strongly suspected to have CdLS have negative genetic testing, indicating that there are additional genes associated with the condition. HDAC2 codes for histone deacetylase 2 (HDAC2) and, like HDAC8, is a Class 1 histone deacetylase. We present a patient with a novel de novo variant in HDAC2 with many clinical features consistent with CdLS including severe developmental delay, limb abnormalities, congenital heart defect, cryptorchidism and hypoplastic genitalia, growth retardation, and characteristic craniofacial features. Although variants in HDAC2 are not currently associated with human disease, the variant identified in this patient is within a highly conserved amino acid residue and has not been observed in healthy populations. This information, along with the patient's clinical presentation and the functional similarity between the HDAC2 and HDAC8 proteins, suggests that HDAC2 should be further investigated as a candidate gene for CdLS or a CdLS-like syndrome.
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http://dx.doi.org/10.1002/ajmg.a.61101DOI Listing
May 2019