Identification of DCAF1 by Clinical Exome Sequencing and Methylation Analysis as a Candidate Gene for Autism and Intellectual Disability: A Case Report.

Autism spectrum disorder (ASD) comprises a heterogeneous group of neurodevelopmental disorders and occurs in all racial, ethnic, and socioeconomic groups. Cutting-edge technologies are contributing to understanding genetic underpinnings in ASD. The reported patient is a 32-year-old male and as an infant was noted to have microcephaly, hypospadias, pulmonary vascular anomaly, and small stature. He was diagnosed with Cornelia De Lange Syndrome (CDLS) at that time based on the clinical features. As a child, he had autistic features and intellectual disabilities and as diagnoses with autism and intellectual disability. He was referred as an adult to our neurodiversity clinic and a full exome trio sequencing with reflex to mitochondrial genes identified a de novo variant of uncertain significance in a candidate gene, DCAF1. The specific variant was c.137 C > T (p.Thr46Ile) in exon 4 in the DCAF1 gene. In silico analysis supports a deleterious effect on protein structure/function. DCAF1 participates with DDB1 and CUL4 as a part of the E3 ubiquitin ligase complex. The E3 ligase complex has been associated with a syndromic form of X-linked intellectual disability. The DDB1/CUL4 E3 ubiquitination complex plays a role in methylation-dependent ubiquitination. Next, a methylation study identified a signature similar to the methylation pattern found in X- linked intellectual disability type 93. This is associated with variants of the BRWD3 gene, which is linked with the functioning of the DDB1/CUL4 E3 ubiquitination complex. Taken together, this suggests that the de novo DCAF1 variant may be a newly identified molecular cause of autism and intellectual disability.

Economic grand rounds: Income inequality and depression prevalence across the United States: an ecological study.

Research has shown a relationship between income inequality and poor health. This column reports findings from a state-level study of the relationship between income inequality and the prevalence of depression. Estimates of depression prevalence by state, obtained from the Behavioral Risk Factor Surveillance System, were linked with Gini coefficients for U.S. household income, obtained from the Census Bureau. The current prevalence of depression was significantly associated with income inequality--the more unequal, the higher the depression prevalence. The association persisted after adjustment for income per capita, percentage of the population with a college degree, and percentage over age 65 years.