When it comes to researching autism and other developmental disorders, it's been almost all about the moms. Her age. The age of her eggs. The risk of the birth. But a new study shows that older dads are more likely to have a child with autism or schizophrenia, and the mother's age may not have a role in the risk for those disorders.
The European study, published in the journal Nature, is being lauded by U.S. physicians as very well done and a breakthrough that may change how we research and try to curb the surge in autism. As the NYTimes reports: "The findings counter the longstanding assumption that the age of the mother is the most important factor in determining the odds of a child having developmental problems. The risk of chromosomal abnormalities, like Down syndrome, increases for older mothers, but when it comes to some complex developmental and psychiatric problems, the lion’s share of the genetic risk originates in the sperm, not the egg, the study found."
Older sperm appear to have a higher risk of random mutations that cause autism and schizophrenia. The study found that children born to a 20-year-old father had an average of 25 mutations that could be traced to the dad's sperm, and the number of mutations increased at a steady rate of two per year. Children with 40-year old fathers had an average of 65 mutations that can be attributed to the sperm (not to worry too much: this translates to an autism risk of 2 percent, at most, for dads 40 and over, experts say). The average number of mutations linked to the mom was 15, regardless of her age. As you might guess, other unknown biological factors are still at play in these disorders, so further research is needed.
But let's talk about gender roles here. I don't know about you, but I've heard multiple female friends say (some in jest, others pretty serious) that they're thinking of freezing their eggs, either until they find a partner or until they and their partner are ready for kids (finances playing a big role in the postponement). Well, this study could be a bit of a game changer.
Sure, maternal age is still an important factor in genetics and pregnancy, but it might be time to think about freezing dear ol' dad-to-be's sperm, also or instead. In response to this study, health experts have even said that the findings shouldn't deter older fathers from bearing kids, but it might be wise to bank some sperm if fatherhood isn't in the cards until later in a man's life.
Not to play the blame game (we all want the best possible health and developmental scenario for our kids, and there's still a lot of research to be done), but the feminist in me isn't surprised that the U.S. (capital of trophy wife-seekers?) hasn't come out with a major study like this (that I know of), focusing on the role of sperm in disorders. As we've seen with the "Mommy Wars," women love to blame women and carry the bulk of the guilt for anything that affects our kids. In research, as in child-rearing, don't forget the dad factor!
What's your reaction to this study? Enlightening? Duh -- of course sperm quality plays a role? Hopeful for an autism breakthrough? Off to the sperm bank? Please share your thoughts!