So, how old was your dad when you were born?
September 5, 2006 Leave a comment
In a very intriguing study just released, it turns out that the incidence of autism is positively correlated with the age of the child's father, but not the mother. Based on a huge study in Israel, here's the heart of the findings in a nutshell:
risk of developing autism of children of fathers in their teens and
twenties. Compared with the offspring of the youngest fathers, children
of fathers in their forties have more than five times the risk of
developing autism, and children of fathers in their fifties have more
than nine times the risk.”
When I mentioned this to my finding to my wife today, she mentioned that perhaps there is something about men who reproduce later in life, rather than a pure biological-age factor. Or as William Saletan put it in today's “Human Nature” column:
Actually, I find this quite an intriguing hypothesis to be at least partially explanatory. Autism is well-understood to be a “spectrum” disorder that ranges from an unfortunate full-blown case, such as my older brother, who cannot talk and has many self-injurious behaviors, to incidences so mild that they are not clinically diagnosed. At some point, there is no bright, clear line between clinically defined autism (or Asperger's Syndrome) and a person who just has significant deficits in their social skills. Such a person, would seem more likely to not reproduce until later in life. Such a person with just some genetic elements of autism, but not a clearly definable case, would seem to be more likely to have offspring with autism. Anyway, just a thought…