Scientists have taken a promising step forward in untangling the genetic roots of autism. Inheritance of a common variant of a gene that influences immunity, gastrointestinal repair, and brain growth substantially raises the chances of developing autism, at least in families with more than one child diagnosed with the severe brain disorder, a study finds.
Children with autism show severe social difficulties, language problems, and repetitive behaviors. The gene, called MET, regulates production of a protein that influences cell proliferation in various parts of the body.
"This is a moderate-to-high-risk autism-vulnerability gene," reports developmental neurobiologist Pat Levitt of Vanderbilt University in Nashville.
Certain variants of the gene, which contain minor alterations in their genetic code, cause several cancers.
Levitt's group had explored how MET contributes to brain development. After learning that the gene lies on a stretch of