Further Delineation of the Proximal 16p11.2 Microdeletion Syndrome: Novel Findings Among 22 New Individuals.

The recurrent chromosome 16p11.2 BP4-BP5 microdeletion (MIM #611913) predisposes to a neurodevelopmental disorder with variable associated congenital anomalies and susceptibility to early-onset obesity. We identified 22 new individuals with proximal 16p11.2 deletions through retrospective data analysis at our institution and performed phenotyping through in-depth chart review. Our cohort exhibited a spectrum of neurodevelopmental abnormalities largely consistent with other publications, however they also were found to have a higher rate than expected of congenital anomalies, some of which have not yet been reported in association with 16p11.2 microdeletions to our knowledge. This series contributes to the body of data on this population, which we anticipate will continue to evolve along with increased uptake of genetic testing.