EBD Blog

Professor Lauren Weiss and colleagues form the Autism Consortium published a paper in the prestigious New England Journal of Medicine today that provides further and stronger evidence about genetic problems underlying Autism. They have identified changes in genetic structure that appear in a small number of children but not in those children’s parents.

Published at www.nejm.org January 9, 2008 (10.1056/NEJMoa075974)

Association between Microdeletion and Microduplication at 16p11.2 and Autism

Lauren A. Weiss, Ph.D., Yiping Shen, Ph.D., Joshua M. Korn, B.S., Dan E. Arking, Ph.D., David T. Miller, M.D., Ph.D., Ragnheidur Fossdal, B.Sc., Evald Saemundsen, B.A., Hreinn Stefansson, Ph.D., Manuel A.R. Ferreira, Ph.D., Todd Green, B.S., Orah S. Platt, M.D., Douglas M. Ruderfer, M.S., Christopher A. Walsh, M.D., Ph.D., David Altshuler, M.D., Ph.D., Aravinda Chakravarti, Ph.D., Rudolph E. Tanzi, Ph.D., Kari Stefansson, M.D., Ph.D., Susan L. Santangelo, Sc.D., James F. Gusella, Ph.D., Pamela Sklar, M.D., Ph.D., Bai-Lin Wu, M.Med., Ph.D., Mark J. Daly, Ph.D., for the Autism Consortium

ABSTRACT

Background: Autism spectrum disorder is a heritable developmental disorder in which chromosomal abnormalities are thought to play a role.

Methods: As a first component of a genomewide association study of families from the Autism Genetic Resource Exchange (AGRE), we used two novel algorithms to search for recurrent copy-number variations in genotype data from 751 multiplex families with autism. Specific recurrent de novo events were further evaluated in clinical-testing data from Children’s Hospital Boston and in a large population study in Iceland.

Results: Among the AGRE families, we observed five instances of a de novo deletion of 593 kb on chromosome 16p11.2. Using comparative genomic hybridization, we observed the identical deletion in 5 of 512 children referred to Children’s Hospital Boston for developmental delay, mental retardation, or suspected autism spectrum disorder, as well as in 3 of 299 persons with autism in an Icelandic population; the deletion was also carried by 2 of 18,834 unscreened Icelandic control subjects. The reciprocal duplication of this region occurred in 7 affected persons in AGRE families and 4 of the 512 children from Children’s Hospital Boston. The duplication also appeared to be a high-penetrance risk factor.

Conclusions: We have identified a novel, recurrent microdeletion and a reciprocal microduplication that carry substantial susceptibility to autism and appear to account for approximately 1% of cases. We did not identify other regions with similar aggregations of large de novo mutations.

Link to the NEJM page for this abstract. Also see a previous post from EBD Blog on de novo substitution, another post about paternal age, and the EBD Blog page about paternal age.