But there is a growing body of evidence that the fruit of aging loins is burdened with increased risk of a wide variety of gene-influenced illnesses

Ideas & Trends: Reproductive Gerontology; Ask Not for Whom the Clock Ticks
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By TAMAR LEWIN
Published: April 15, 2001
MEN, take note: you, too, have a biological clock.
True, it does not tick toward the absolute deadline that ends women's childbearing years. As notables like Tony Randall, Yasir Arafat, George Plimpton, Anthony Quinn, Clint Eastwood, Strom Thurmond and so, so many more have demonstrated, men can father babies no matter how old they get.

But there is a growing body of evidence that the fruit of aging loins is burdened with increased risk of a wide variety of gene-influenced illnesses

c. A study released last week raised the intriguing -- if skeptically viewed -- possibility that some cases of schizophrenia fall into that category.

The study found that older fathers are more likely to have children with schizophrenia. Fathers over 50 have three times the risk of having a child who develops schizophrenia as fathers under 25, the study found. Earlier studies linked advanced paternal age to a variety of conditions, including the most common type of dwarfism, neural tube defects, nervous system cancer, prostate cancer, neurofibromatosis, Apert syndrome (a malformation of the skull, hands and feet) and Marfan syndrome, which involves defects of the eyes, bones, heart and blood vessels. The study does not address what it is about the father that could cause schizophrenia. But Dr. Dolores Malaspina, a researcher at Columbia University and the lead author of the schizophrenia study, said that scientists have been seeing signs of a male biological clock for some time. ''While scientists have known for years that older fathers are a major source of gene mutations,'' she said, ''the public doesn't seem to have absorbed it, which may have something to do with a culture that sees older fathers as triumphantly virile.''

As research continues, her team suggested, it may be that the father's sperm will turn out to play as big a part in children's genetic problems as the mother's eggs.

While women are born with all the eggs they will ever have, the cells that become sperm divide and reproduce throughout a man's life -- with each division introducing a slight risk of error in the genetic material the new sperm passes on to the children. For men in their 40's and 50's, who assumed they could defer parenthood to their later, quieter years, the possibility of a male biological clock is not a happy concept.

''This is a new idea to me, and it doesn't make my day,'' said Gregory Mosher, a New York director and producer. ''But science is so mind-boggling that there always are new discoveries that make you rethink all your assumptions. This is just another thing to talk about with whoever you're making the decision with.''

And some men reacted by pointing out that, if they do have such clocks, they tick quietly. ''I know that the problem women face with their biological clock is something I'll never experience or fully understand,'' said Richard Orloff, a playwright. ''For men, even if there's some higher risk of having a child with a problem, there's still the possibility of being a father.''

If, as the new study suggests, one-fourth of all schizophrenics have older fathers, it may seem puzzling that the correlation was not noticed long ago. But what scientists find depends on what they look for, as women angered by the lack of female-specific data on problems like heart disease have long pointed out.

''We've known since the 1960's that schizophrenia is associated with last-born kids and older parents,'' said Dr. Malaspina. ''But most people choose spouses about their age, and if you didn't look specifically at the father's age, you would think there was a powerful link between maternal age and schizophrenia. It's only when we separated it out that we saw that paternal age mattered, and maternal age didn't.''

There is a particular irony in the finding that the devastating mental illness once thought to be caused by a type of bad mother -- the ''schizophrenogenic'' mother, a staple of 60's psychiatry -- may have something to do with the father.

THE BEST TIME FOR A MAN TO FATHER A HEALTHY CHILD IS 25 OR SO THE SAME AS FOR A WOMAN

Like eggs, sperm have a "best by" date?




http://seattletimes.nwsource.com/html/health/2003303295_carnalknowledge15.html

By Faye Flam

By the time I'd reached my early 30s and was still not married, someone offered me this bit of advice: Just pick somebody.

Women are relentlessly reminded of the dreaded biological clock and the risks of having children after 35. But recent science suggests men, too, should be worried.

"The term 'biological clock' has always referred to females, but now there's evidence men are also ticking off some of their healthy children," says Jay Schinfeld, a fertility specialist.

The latest finding, published last month: Older fathers are more likely to have children with autism. Researchers tracked 387,000 people born in Israel and concluded the odds of fathering an autistic child are about 6 in 1,000 for men under 20. When a man reaches 50, those odds shoot up to about 52 in 1,000.

"The optimal time for a man to father a healthy child is the same as for a woman — 25 or so," says Dolores Malaspina, a psychiatry professor at New York University and coauthor of the study.

Malaspina led an earlier study showing a connection between paternal age and schizophrenia. She found children born to fathers over 50 carried about three times the risk of developing schizophrenia as those born to fathers in their 20s.

Autism and schizophrenia both arise from a little-understood combination of genetic and environmental triggers. Both disorders tend to run in families, suggesting that genetic risk factors can be inherited.

But you don't have to carry a genetic disease to pass one on — the trouble can start in your testicles. There, sperm-generating cells divide about 23 times a year, in the process slowly accumulating copying errors.

Older fathers are more likely to have children with achondroplasia (dwarfism) and several other conditions caused by spelling errors in the DNA. So for a man, the older you get, the less your child's genetic endowment will resemble your own.

For women, aging isn't as likely to lead to spelling errors because we make no new eggs after we're born. But that leads to other problems. The million or so we begin life with die at a rate of about 30 a day, and as the remaining eggs age, they get less adept at one of their critical jobs — dividing their 46 chromosomes in half. Eggs don't do this until after they're penetrated by a sperm.

If they get it wrong, some will get extra chromosomes, others will miss one, leading to Down syndrome (an extra chromosome 21), Turner's syndrome (a missing X chromosome in a girl), and Klinefelter's syndrome (an extra X chromosome in a boy).

Menopause creates a natural cutoff for women's fertility around 50, while an increasing number of men much older than that are becoming fathers, or trying to, says Abington's Schinfeld. "We get some as old as 70 coming here to try to make babies," he says.

Some get married a second time to a younger woman and others find love late in life. Schinfeld said one of his patients, a Vietnam veteran in his 60s, came to him with a wife in her 30s. The man explained that during the war he'd rescued a group of villagers, including a little girl, and that girl tracked him down after she grew up. Despite the age difference, they fell in love and got married.

It's hard to say whether men will now be subject to pressure the way women are, or accused of "wanting it all."