Autism 'caused by genetics', study suggests

[proverbialwisdom]

59. READ: 5/2014 JAMA study of 2 million people in Sweden from '82-'06, "The Familial Risk of Autism."

http://www.bworldonline.com/weekender/content.php?id=87123

Posted on 05:23 PM, May 08, 2014

Autism risk is half genetic, half environmental: study

WASHINGTON -- A large study in Sweden has shown that genes are just as important as environmental factors in assessing the causes of autism.

Researchers were surprised to discover that the inheritability of the neurodevelopmental disorder was about 50% -- much lower than previous studies that put it at 80-90% -- and that it was equal to environmental causes, according to the study published in the Journal of the American Medical Association.

The findings were based on data from more than two million people in Sweden from 1982 to 2006, and is the largest to date on the topic of understanding whether genes or the environment contribute to autism, which affects about one in 100 children globally, and as many as one in 68 in the United States.

“We were surprised by our findings as we did not expect the importance of environmental factors in autism to be so strong,” said study author Avi Reichenberg from the Mount Sinai Seaver Center for Autism Research in New York.

The study did not pinpoint which environmental factors could be at play, but said generally they could include things like the family’s socioeconomic status, birth complications, maternal infections or medications taken before and during pregnancy.

Co-authors on the study came from Kings College London and Karolinska Institutet in Sweden.

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http://jama.jamanetwork.com/article.aspx?articleid=1866100

May 7, 2014, Vol 311, No. 17 >

Original Investigation | May 7, 2014

The Familial Risk of Autism FREE

Sven Sandin, MSc1,2; Paul Lichtenstein, PhD1; Ralf Kuja-Halkola, MSc1; Henrik Larsson, PhD1; Christina M. Hultman, PhD1; Abraham Reichenberg, PhD3,4,5

[+] Author Affiliations
1) Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Sweden
2) Department of Psychosis Studies, Institute of Psychiatry, King’s College London, United Kingdom
3) Department of Psychiatry, Ichan School of Medicine at Mount Sinai, New York, New York
4) Department of Preventive Medicine, Ichan School of Medicine at Mount Sinai, New York, New York
5) Seaver Autism Center and Friedman Brain Institute, Ichan School of Medicine at Mount Sinai, New York, New York

JAMA. 2014;311(17):1770-1777. doi:10.1001/jama.2014.4144.