Defective gene linked to autism symptoms

A defective gene causes brain changes that lead to the atypical social behavior characteristic of autism, U.S. researchers said. Cecilia Giulivi, professor of molecular biosciences at the University of California, Davis School of Veterinary Medicine, and a researcher affiliated with the University of California, Davis MIND Institute, said studies in mice showed abnormal action of just one gene disrupted energy use in neurons. The harmful changes were coupled with anti-social and prolonged repetitive behavior -- traits found in autism, Giulivi said. "A number of genes and environmental factors have been shown to be involved in autism, but this study points to a mechanism -- how one gene defect may trigger this type of neurological behavior," Giulivi said in a statement. "Once you understand the mechanism, that opens the way for developing drugs to treat the condition." The research, published in the journal PLoS ONE, showed, when defective, the gene's protein interacts with the protein of a second gene known as p53 to dampen energy production in neurons. This severe stress leads to a spike in harmful mitochondrial DNA changes and abnormal levels of energy production in the cerebellum and hippocampus -- brain regions critical for social behavior and cognition, Giulivi said.