Thursday, January 31, 2008

Autism and Paternal Age

Paternal age is emerging as a potential cause or causal factor giving rise to autism. On this site, (as a father whose autistic son was conceived when I was 41), I have received several posts from a blogger/poster who has focussed on this issue . In Australia, reports that researchers at the Queensland Centre for Mental Health Research have found:

"adult mice born to older fathers have differently shaped brains and are generally more anxious and less adventurous than those fathered by younger animals. ... brain scans of the mice showed those born to older fathers had thicker cerebral cortexes."

The research team's senior investigator, John McGrath explains that "What we've found in the mice is reminiscent of autism because there's some reasonable evidence about early brain overgrowth in autism". McGrath also stated that the results need to be replicated before they are given scientific validity.

The article by reporter Janelle Niles states that previous population studies have found a six-times increased likelihood of autism than those born to dads in their 20's. Unlike my friends at Autism Street I am no statistician but on a common sense level, if the article information is correct, a six-times increased likelihood of autism in offspring for Dad's in their 40's compared to Dads in their 20's would seem to be .... statistically significant ... one which should be the focus of further research.

1 comment:

Anonymous said...

Very Interesting! This was just a conference presentation so it will be a while before the article gets published. The population data is very interesting and honestly I was not familiar with it. But some preliminary and very general food for thought about animal research: I know many many researchers that will hit the roof with the implication of "autistic" characteristics found in mice. The jump between animal and human literature is usually made once there is tons of animal evidence in very specific areas where anthropomorphizing is appropriate. The jump from "less adventurous" behaviors to autism is well.. enormous! :-) Actually, less adventurous rodents are usually called "low responders" and this is a common finding in rodents with overactive stress systems. These "shy" behaviors are usually viewed as "low activity" behaviors responding to increased stress signals, just like socially withdrawn kids (not kids with autism). So in humans we make a very strong qualitative distinction between children who are shy and children who have autism. And as we know, this distinction is extremely difficult to make at some degrees of both shyness and autism. Imagine how impossibly difficult it is to make this distinction at the rodent level! :)
Very interesting post. Cheers.