Chicago – Men who become fathers in their 40s or older are much more likely to have autistic children than younger dads, a new study released Monday shows, bolstering evidence that genetics contributes to the mental disorder.
The research involved about 130,000 Israeli Jews born in the 1980s. Those fathered by older men were almost six times more likely to have autism or related disorders than those fathered by men younger than 30, and more than one-and-a-half times more likely than children fathered by men ages 30-39.
The mothers’ age at childbirth appeared to have little impact on autism, although the researchers said they couldn’t rule out “a possible small effect” from the oldest mothers.
Autism experts called the study intriguing but not definitive, and the authors said the results need to be tested in a broader population to see if similar findings would occur in other ethnic groups.
It’s not the first time fathers’ age has been implicated in autism, but the new research stands out because “it’s a strong effect in a carefully designed study,” said Dr. Edwin Cook, an autism researcher at the University of Illinois-Chicago who was not involved in the study.
The study was released Monday in September’s Archives of General Psychiatry.
It is based on biographical information on Israeli boys and girls who at age 17 were being assessed for eligibility to serve in the Israeli military. Among them, 110 had been diagnosed earlier with autism or related disorders, including a less severe condition called Asperger’s syndrome.
However, most of the affected children in the study had autism, and the researchers said their results may not apply to Asper ger’s or other autism-like disorders.
