And we turn next to healthy living. A thunder bolt today about fathers, mothers and autism in children. We've heard so often about the age of the mother as a risk factor in genetic disorders. But... See More
And we turn next to healthy living. A thunder bolt today about fathers, mothers and autism in children. We've heard so often about the age of the mother as a risk factor in genetic disorders. But today, a study from the journal "nature" provides new evidence about the age of the father, and how that affects the risk. Here's abc's medical editor dr. Richard besser. Reporter: Autism, one of medicine's greatest puzzles, has some new math, about older dads. Dads like ray siegel. Let's figure out if there's a genetic factor. Reporter: His sons oscar and hugo are both youautistic. For the first time, sign tilss are spelling out mathematically, who the je neatic material in men changes as they age. Unlike moms, dads have an average of 25 mutations at age 20, growing to 65 mutations at age 40. Could that be part of the reason that older men, particularly dads over 50, are much more likely to father an autistic child? We know dads who are over 50, when compared to dads over 30, have twice the risk. We've known for some time that spontaneous mutations probably were significantly more common in children with autism. What we didn't know is how much more common. Reporter: But father's age still only explains about 5% of the risk of autism. But one thing is clear. Men have a biological clock, too. And I want to make it clear that the risk from being an older father is still very small and nobody is saying to older men that they shouldn't have children. Diane, but this does provide another clue to autism. It does. And thank you, rich besser,
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