While a woman’s age is definitely a contributing factor in the health of her babies, a growing number of studies suggest men should heed the ticking of their biological clocks, too.
Recently, City of Hope researchers added to the evidence when they found that risk of non-Hodgkin’s lymphoma is higher for children of older men.
|Yani Lu (Photo by p.cunningham)|
The study is one of the first to check on the relationship between parents’ age and the likelihood their grown children will face cancers of the blood and immune system.
“As a man, you may think, ‘I can have a baby at 50 or 60 and live long enough to see him go through college.’ But there may be other risks for your child down the line, and you may want to be conscious of those risks,” said study leader Yani Lu, Ph.D., a postdoctoral fellow in the Division of Cancer Etiology.
Lu’s research focused on nearly 111,000 women, more than 800 of whom had been diagnosed with a cancer of the blood or immune system. She and her colleagues found that those born to fathers older than age 40 faced a 59 percent greater risk of non-Hodgkin’s lymphoma compared to similar women born to fathers younger than 25.
“For adult-onset malignancies, people seldom think back” to factors early in life, Lu said. Diagnosis for non-Hodgkin’s lymphoma typically occurs closer to the age of 70, so few would connect the illness to factors arising before they were born, she explained.
In the study, the fathers’ age had no effect on risk for acute myeloid leukemia or multiple myeloma. And the mother’s age did not significantly influence risk for blood cancers.
Science has shown that the ticking biological clock is linked to a higher incidence of health issues in children of older mothers. These women face greater risk of miscarriage and increased risks of bearing children with low birth weight or serious health issues.
Similar findings among older fathers are scanty, although research going back almost 100 years suggests that older men are more likely to produce children with certain rare birth defects. Numerous studies also show that offspring of older men have a greater risk of developing schizophrenia.
As Lu noted, however, growing evidence suggests a father’s age at his baby’s conception may play a more significant role in his child’s lifetime health than once thought. Recent studies indicate that children of older fathers have a greater chance of prostate and breast cancers in adulthood as well as some blood cancers during childhood.
Lu believes the male biological clock might relate to mutations that can build up in a man’s reproductive cells over the course of his lifetime. Such cells divide more rapidly than a woman’s reproductive cells. More divisions lead to more chances for abnormalities to arise.
Parents’ ages also appear to be a factor in the length of their child’s telomeres, which are the end caps on chromosomes. Telomere length might be linked to non-Hodgkin’s lymphoma risk, Lu suggested.
Also, non-Hodgkin’s lymphoma is actually a group of related diseases with about 30 subtypes. So Lu plans to examine how the age of a person’s father and other health factors during the early years of life affect risk for specific disease subtypes.