Older paternal age
 

Hello,
Just wondering on everyone's thoughts on the studies that are showing increased paternal age at time of conception directly relating to the increased chances of the child having autism. It seems like studies are all over the place proving and disproving this.

I think that this is complicated - it seems that the effects of paternal and maternal age are different.

It is discussed here http://www.medscape.com/viewarticle/846265 , including a link to a free-access version of a very large recent study.

Paternal age as a contributor to autism fits quite well with recent evidence that autism is programmed by epigenetic proteins. Women's epigenetic contribution is secured and fixed at the age of puberty. Girls can change and degrade epigenetic contribution before puberty. However, the female contribution is not paraded through very many bad influences. And it has the protections offered by a young vigorous immune system.

None of this is true of fathers. Men change their epigenetic contributions throughout life, and are subject to cumulative exposure to chemicals, bad eating habits and disease.