TAU: Schizophrenia family history may lead to autism

Autism Spectrum Disorders are developmental disorders diagnosed in one in 88 children, but new Tel Aviv University and Sheba Medical Center research has found that ASD shares a root cause with psychiatric illnesses like schizophrenia and manic-depression (bipolar disorder).

Dr. Mark Weiser of Tel Aviv University’s Sackler Faculty of Medicine and the Sheba Medical Center has revealed a family history of the psychiatric diseases is a risk factor for autism, which affects boys more often than girls and is usually diagnosed around age two. The findings have been published in the journal Archives of General Psychiatry.

At first glance, schizophrenia and autism look like very different illnesses, he says.

But closer inspection reveals many common traits, including social and cognitive dysfunction and a decreased ability to lead normal lives and function in the real world.

ASD, a category that includes autism, Asperger syndrome and pervasive developmental disorder, is characterized by difficulty with social interaction and communication or repetitive behaviors. It is better diagnosed today, but nevertheless, it seems to be much more common now; there has been a 10-fold increase in the last four decades.

Studying extensive databases in Israel and Sweden, the researchers discovered that the two illnesses had a genetic link, representing a heightened risk within families.

They found that people who have a schizophrenic sibling are 12 times more likely to have autism than those with no schizophrenia in the family. The presence of bipolar disorder in a sibling showed a similar pattern of association, but to a lesser degree.

Regarded by experts as a scientific leap forward, the study sheds new light on the genetics of these disorders. The results will help scientists better understand the genetics of mental illness, said Weiser on Tuesday, and may prove to be a promising direction for future research.

The researchers used three data sets, one in Israel and two in Sweden, to determine the familial connection between schizophrenia and autism. The Israeli database alone, used under the auspices of the ethics committees of both the Sheba at Tel Hashomer and the Israeli Defense Forces, included anonymous information about more than a million soldiers, including patients with schizophrenia and ASD.

“We found the same results in all three data sets,” Dr. Weiser said, noting that the ability to replicate the findings across these extensive databases is what makes this study so significant.

Understanding this genetic connection could be a missing link, Weiser added. He and his colleagues are now taking their findings in a clinical direction. For now, though, the findings shouldn’t influence the way that doctors treat patients with either illness, he added.

This work was done in collaboration with researchers at the University of North Carolina, Karolinska Institute in Sweden, Kings College London, and the IDF Medical Corps.