“Signatures” of Errant Gene Expression in Autism Eyed for Diagnostic Test

August 1, 2008 • Science Update

Researchers have launched an effort to detect profiles of gene expression associated with autism that could some day form the basis of a diagnostic test for the disorder. The study, supported by a new grant from NIMH's Division of Neuroscience and Basic Behavioral Science, is searching for "signatures" in patterns of such expression in autism that could be clues to underlying abnormalities in the machinery that turns genes on and off in response to experience, as the brain is wired up during the first years of life.

The signatures could ultimately lead to development of a diagnostic test that could help researchers screen families and aid in development of improved treatments, according to grantee Louis Kunkel, Ph.D., of Harvard Medical School and Children's Hospital Boston.

His research team is comparing the expression of messenger RNA , which translates the genetic blueprint into proteins, in hundreds of children with autism and their parents with that of healthy controls. They are also re-sequencing suspect genes in hundreds of such subjects, looking at areas that control gene expression as well as protein-coding areas for disease-causing variations. Particularly telling would be aberrant patterns in the way genes are spliced, which could be influenced by environmental events during later stages of neuronal development.

The researchers hope to identify changes in the sequence of the genetic code that could explain the telltale gene expression signatures and point to the biological pathways by which environmental insults might influence the process. There could be common mechanisms underlying the seemingly disparate deletions and duplications of genetic material increasingly reported in autism, says Kunkel.