We have known for a while that there was a correlation between having an older father and having an increased likelihood of having autism. It was once thought that this was because of an increase in de novo mutations in sperm, but recent research says that that can only account for 20% or so of autism cases.
If it’s not new mutations, what’s the explanation?
The authors of the linked piece suggest that perhaps it’s because men with autistic traits marry later in life. In my case, that was certainly true. I started dating very late in life, and I only met my wife when I was 33. My daughter was born when I was 35. My autistic son, Daniel, was born when I was 38. And Dylan was born when I was 40. Dylan does not have autism, but he did have a language delay and he has a degree of OCD, and it seems he has perfect pitch (a trait found in many autistics and their near-relatives). I of course am on the Asperger’s end of the spectrum.
Getting into the kinds of relationships that result in children is difficult at best for us on the spectrum. Some, like Temple Grandin, choose celibacy because these relationships are so complex and difficult. Many solve the problem by marrying someone else on the spectrum. And I’m willing to bet those are also delayed relative to when most people marry and have children.
It will be interesting to see a study on this, to see if it holds up. But given the nature of people on the spectrum, and given the fact that autism is genetic and thus completely heritable, it wouldn’t surprise me in the least if the explanation were simply that autistic people tend to marry and have children later in life.