Friday, February 12, 2010

Older Fathers Increase the Risk of Autistic Kids

A new large-scale study in California found that father's age, more than mother's age, increases the risk of having an autistic child. The core finding:

The new study suggested that when the father was over 40 and the mother under 30, the increased risk was especially pronounced — 59 percent greater than for younger men.


LMR said...

I read a report of this study on Scientific American and while it doesn't contradict the quote you have here, it characterizes it in a different way:

But the current study found that paternal age is only a risk factor when the mother is under 30....pooling data artificially inflates the risk of paternal age, and that advanced maternal age likely poses the greater risk.

This article emphasizes instead this finding: "The researchers found that mothers over 40 had a 51 percent higher risk of having a child with autism than mothers 25 to 29, and a 77 percent higher risk than mothers under 25." And "It really is a maternally mediated biological process that's going on."

randy said... what is the actual rate of autistic infants per 100,000 babies born?

is there even a coherant definition of 'autism'? or is it more of a judgement call?

are there degrees of autistic severity?

do other non-genetic factors promote or inhibit the manifestation of autistic characteristics?

see? it's more complex than 'doing x doubles the risk for y.' these sorts of simplistic, alarrmist statements annoy me.

Pug said...

My wife is a diagnostician for an elementary school in Texas. The autism diagnosis is very popular today. ADD and dyslexia were once popular but are now passe. Teachers tend to push to have children labeled because then they get help with the child. Apparently it is fairly easy to game the system.

Gruntled said...

Fair enough to all comments.

I think that aging moms affect fetal health more than aging dads. It does make sense to me, though, that even if fathers make new sperm, the aging sperm factory is more likely to mess up than it did when it was newer.

As to the faddishness of the autism diagnosis, I will grant that. Nonetheless, I don't think teachers and psychologists are more likely to reach an autism diagnosis just because the parents are older. SO whatever the criteria for the diagnosis are, if it is more likely to be reached when the parents are older, this suggests that parental age really does matter in producing whatever it is that is being diagnosed as autism.