Study links older dads with health of grandkids
By Malcolm Ritter , AP
June 13, 2012, 12:09 am TWN
NEW YORK--Finally, some good news for older dads. A new study hints that their children and even their grandchildren may get a health benefit because of their older age.
It's based on research into something called telomeres — tips on the ends of chromosomes.
Some previous studies have associated having longer telomeres (TEE-loh-meers) with better health and longer lives. Telomeres haven't been proven to cause those benefits in the general population, but a number of researchers think they may hold secrets for things like longevity and cancer.
As you age, telomeres shorten. However, previous studies have shown that the older a man is when he becomes a father, the longer the telomeres his children tend to have. The new research confirms that and finds it's extended to the grandchildren.
That's a cheerier result for older dads than some other studies in recent years that indicate their kids are at heightened risk for things like autism, schizophrenia and bipolar disorder.
The new work didn't look at health outcomes. That's a future step, said researcher Dan T.A. Eisenberg of Northwestern University. He presents the results with colleagues in Monday's issue of the Proceedings of the National Academy of Sciences.
Carol Greider of Johns Hopkins University, who shared a Nobel Prize in 2009 for telomere research but who didn't participate in the new study, said it's no surprise that the telomere effect would extend beyond children to grandchildren.
She cautioned that since older fathers also tend to pass more potentially harmful genetic mutations, it's "not at all clear" whether advanced paternal age gives an overall health benefit to children. In a statement, the Northwestern researchers said their study shouldn't be taken as a recommendation that men reproduce at older ages, because there's a risk of mutations.
One analysis of about 2,000 people confirmed the idea that the older your dad was when you were born, the longer your telomeres tend to be. That held true throughout the age range of the fathers, who were 15 to 43 at the time their sons or daughters were born.
Researchers then extended that another generation: The older your father's father was when your father was born, the longer your telomeres tend to be. That analysis included 234 grandchildren. A separate analysis found no significant effect from the mother's father.