Research identifies genetic link between GI problems, autism

A significant proportion of people with autism have some form of gastrointestinal distress. A gene that affects how neurons communicate in the brain and the way the digestive system defends itself may be the common root of these ills, according to a study in the March Pediatrics.

"Our study brings together genetic risk for autism and co-occurring GI disorders in a way that provides a biologically plausible explanation for why they are seen so often together," said Pat Levitt, PhD, one of the study authors and director of the Zilkha Neurogenetic Institute at the University of Southern California's Keck School of Medicine.

Researchers analyzed the genomes of 918 people from 214 families taking part in the Autism Genetics Resource Exchange. An allele of the MET C gene was associated with autism spectrum disorder and gastrointestinal problems in 118 of the families with at least one child with both conditions. This gene was not linked to autism in the 96 families with at least one child with the neurological disorder but no sign of digestive problems.

The authors suggest this discovery is a step toward further subtyping autism. It also could lead to identifying treatments that might be most effective for this group.

"Autism is heterogeneous. It's a disorder where two kids with autism rarely have the same symptoms," said Daniel B. Campbell, PhD, lead author and research assistant professor in the pharmacology department at Vanderbilt University in Tennessee. "If we can identify different types of autism, we may be able to do a better job of designing treatment options."

Future research plans include more precisely defining the nature of the various GI problems to get a better handle on the link. Scientists also intend to investigate how this gene affects the immune system.

The study abstract is available online (link).