Published on September 5, 2006 at 6:50 AM
Researchers in the U.S. have found that children fathered by older men have a higher risk of developing autism, possibly because of mutations or other genetic changes.
The researchers from from Mount Sinai School of Medicine, New York, and the Institute of Psychiatry, King's College London say that advanced paternal age is a risk factor for autism spectrum disorder.
Their research was based on records from the Israeli draft board medical registry of thousands of children born during the 1980s.
All males and three-fourths of the females born in the time period involved were checked by Israeli draft officials at age 17 and any psychiatric disorders were recorded.
The researchers found that children of men 40 years or older were almost six times as likely to have children with autism disorders when compared with offspring of men younger than 30 years.
However the researchers say advanced maternal was not a risk factor for the disorder.
Autism spectrum disorders result in a range of symptoms and severity ranging from social isolation to repetitive and damaging behaviours and sometimes mental retardation and are generally disabling for the individual.
The problem has become increasingly common, worldwide affecting far more boys than girls.
As many 50 in every 10,000 children in the United States are affected, and the exact cause remains debatable.
There is no cure and treatment varies and relies heavily on managing behaviours.
The study suggests genetic mechanisms might be the reason for the paternal age association found, including spontaneous mutations in sperm-producing cells.
The study is published in the Archives of General Psychiatry.