Mayo Clinic On Autism and Older Fathers One Fact Not Stated is Sperm Cannot Repair Itself

"A really key factor that differentiates sperm from other cells in the body is that they do not repair their DNA damage," he said. "Most other cells do."


On a related note, advancing maternal age appears to have little effect on autism risk.



Older fathers and autism risk: Is there a connection?Date updated: May 31, 2007 Content provided by MayoClinic.com
Is it true that children born to older fathers are at increased risk of autism?
Kristin, Utah
A growing body of evidence suggests that a father's age (paternal age) may play a role in autism risk.
A large study published in the Archives of General Psychiatry in 2006 examined the relationship between advancing paternal age and autism risk. Researchers reported that children born to men 40 years or older were almost six times more likely to have autism spectrum disorder than were children born to men younger than 30 years.
The reason for this increased risk of autism isn't clear. One theory is that as men age, their genetic material loses some ability to repair itself. As a result, spontaneous mutations in genes may be passed on rather than corrected - potentially leading to an increased risk of brain abnormalities in their children. Researchers have identified a number of gene mutations associated with autism.

Research Reveals A Cellular Basis For A Male Biological Clock
ScienceDaily (Nov. 27, 2002) — Researchers at the University of Washington have discovered a cellular basis for what many have long suspected: Men, as well as women, have a reproductive

http://www.sciencedaily.com/releases/2002/11/021126201311.htm

The researchers found that men over age 35 had sperm with lower motility and more highly damaged DNA in the form of DNA double-strand breaks. The older group also had fewer apoptotic cells – an important discovery, Singh said.
"A really key factor that differentiates sperm from other cells in the body is that they do not repair their DNA damage," he said. "Most other cells do."
As a result, the only way to avoid passing sperm DNA damage to a child is for the damaged cells to undergo apoptosis, a process that the study indicates declines with age.
"So in older men, the sperm are accumulating more damage, and those severely damaged sperm are not being eliminated," Singh said. "That means some of that damage could be transmitted to the baby." More research is needed to determine just what the risks are. Other reseachers in the study included Richard E. Berger, UW professor of urology. The work was supported by the Paul G. Allen Foundation for Medical Research.
On a related note, advancing maternal age appears to have little effect on autism risk.