Developmental Delays and DNA Deletions

A DNA deletion can lead to cognitive problems, including autism, developmental delays, and mental retardation, reports MIT's Technology Review. A team led by Evan Eichler screened 5,218 people with autism, congenital abnormalities, or mental retardation and found that 25 of them had similar 1.35 megabase deletions; within a similarly-sized screen of healthy people, no one had that deletion. The deletion includes seven genes, one of which is involved in heart development and another in the development of the eye's lens. The results are reported online at the New England Journal of Medicine.