Terminal microdeletions of 13q34 chromosome region in patients with intellectual disability: Delineation of an emerging new microdeletion syndrome.

The increasing use of chromosomal microarray studies in patients with intellectual disability has led to the description of new microdeletion and microduplication syndromes. We report terminal microdeletions in 13q34 chromosome region in 5 adult patients of two unrelated families. Patients harboring 13q34 microdeletions display common clinical features, including intellectual disability, obesity, and mild facial dysmorphism. These individuals can become fairly self-sufficient, however they do not live independently, and require community and social support. Further systematic analysis of the genes comprised in the deleted region will allow the identification of genes whose haploinsufficiency is expected to lead to disease manifestations, in particular intellectual disability.