May 26, 2011 07:44 GMT  ·  By

Until now, investigators trying to make sense of how autism works were stopped in their tracks by the fact that the mental illness appeared to leave no discernible tracks behind. In a new study, researchers in the United States finally managed to find the molecular effects of autism.

This is the first time that physical traces of autism are discovered in the human brain, say experts from the University of California in Los Angeles (UCLA) research team that conducted the study.

At the molecular level, the autistic brain is significantly different from the healthy one, and now scientists have the necessary knowledge to tell the two apart, Science Blog reports. Both genes and proteins are involved in underlying this difference, the team says.

Details of the new investigation appear in the May 25 advanced online issue of the top scientific journal Nature, and the paper highlights a new, interesting avenue of research in treating autism.

“If you randomly pick 20 people with autism, the cause of each person’s disease will be unique,” Dr. Daniel Geschwind says of the challenges facing experts working in teasing out the root causes of this mental disorder.

“Yet when we examined how genes and proteins interact in autistic people’s brains, we saw well-defined shared patterns. This common thread could hold the key to pinpointing the disorder’s origins,” he goes on to say.

Geschwind holds an appointment as the UCLA Gordon and Virginia MacDonald Distinguished Chair in Human Genetics, and is the principal investigator of the new research. He is also a professor of neurology and psychiatry at the UCLA David Geffen School of Medicine at UCLA.

Working together with colleagues at the University of Toronto and King’s College London, the scientists learned that gene-expression levels in the cerebral cortex differ between the healthy and autistic brain.

“We were surprised to see similar gene expression patterns in most of the autistic brains we studied,” explains UCLA postdoctoral fellow in neurology and first study author Irina Voineagu.

“From a molecular perspective, half of these brains shared a common genetic signature. Given autism’s numerous causes, this was an unexpected and exciting finding,” she concludes.

Funds for this study were secured from the US National Institute of Mental Health (NIMH), the Canadian Institutes of Health Research, and Genome Canada.