Gene Deletion on Chromosome 16 Linked to Autism
Abnormalities at 16p11.2 locus seen in 1 percent of cases of idiopathic autism
WEDNESDAY, Jan. 9 (HealthDay News) -- Deletions or duplications of a region of chromosome 16p11.2 appear to increase susceptibility to autism, according to an article published online Jan. 9 in advance of publication in the New England Journal of Medicine.
Lauren A. Weiss, Ph.D., of the Autism Consortium and the Center for Human Genetic Research in Boston, and colleagues performed a genomewide association study of a sample of 751 families with multiple cases of autism from the Autism Genetic Resource Exchange (AGRE) in order to identify recurrent deletions or duplications associated with autism. Identified events were further evaluated in a sample of 512 children referred to Children's Hospital Boston with developmental delay, mental retardation or suspected autism spectrum disorder, and in a large population study in Iceland.
The researchers identified a microdeletion of 593 kb on chromosome 16p11.2, which occurred in five AGRE families. The identical deletion was seen in five of 512 children from Children's Hospital Boston and in three of 299 autistic persons in the Icelandic population. The reciprocal duplication of this region occurred in seven autistic individuals from AGRE families and in four of the 512 children from Children's Hospital Boston.
"Deletion and duplication events were observed in nearly 1 percent of multiplex families with autism, in 1 percent of subjects with autism in Iceland, and in more than 1.5 percent of clinical samples from subjects with developmental delay," the authors conclude.