Saturday, August 25, 2012

Paternal Age, Press Attention


The Nature study linking paternal age to autism is getting a great deal of media attention. K.J. Dell’Antonia writes at The New York Times:
On Wednesday, various news organizations, including The New York Times on its home page, reported findings of a high-profile study in the journal Nature. There was convincing evidence, the study concluded, that — in a fraction of cases — increased mutations found in the sperm of older men meant that they were more likely than their younger counterparts to father children with autism or schizophrenia.
Reaction was immediate. More than 500 commentersweighed in at NYTimes.comBlogs from SheKnows.com toTime’s Healthland ran with the news. Some sites got accusative: “Are Older Fathers Causing Autism in Their Kids?” demanded the Dadding blog at Babble.com.
The news reflected widespread interest in the confusing causes of this still-unexplained condition. But it also produced a stream of headlines like this one on Jezebel.com“Hooray for the Male Biological Clock!” And female news anchors like CNN’s Ashleigh Banfield cheered the report because, as she put it: “I had my babies at 38 and 39, and I was terrified. Honey, you’re in the conversation now.”
A news article in Nature adds detail:
The results might help to explain the apparent rise in autism spectrum disorder: this year, the US Centers for Disease Control and Prevention in Atlanta, Georgia, reported that one in every 88 American children has now been diagnosed with autism spectrum disorder, a 78% increase since 2007. Better and more inclusive autism diagnoses explain some of this increase, but new mutations are probably also a factor, says Daniel Geschwind, a neuro­biologist at the University of California, Los Angeles. “I think we will find, in places where there are really old dads, higher prevalence of autism.”
However, Mark Daly, a geneticist at Massachusetts General Hospital in Boston who studies autism, says that increasing paternal age is unlikely to account for all of the rise in autism prevalence. He notes that autism is highly heritable, but that most cases are not caused by a single new mutation — so there must be predisposing factors that are inherited from parents but are distinct from the new mutations occurring in sperm. 
The study has even made CBS News: