Y Chromosome Defect Linked To Prostate Cancer Risk

4 January 2007
Y Chromosome Defect Linked To Prostate Cancer Risk
by George Atkinson

A study from Columbia University's Mailman School of Public Health has found that men who had only daughters had a higher risk of prostate cancer than men who had at least one son, thus signifying a possible defect on the father's Y chromosome. Interestingly, the study, in the Journal of the National Cancer Institute, further indicates that the relative risk of prostate cancer decreases as the number of sons increases.

"We surveyed vital status and cancer incidence, and found a strong trend for a decrease in prostate cancer risk as the number of sons increased," said Columbia University's Susan Harlap. Overall, there was a 40 percent increase in prostate cancer in men lacking sons.

The gender of offspring depends on whether the embryo receives an X or a Y chromosome from the father. A man with a damaged Y chromosome will be less likely to have sons and those with a damaged X chromosome may be unable to father daughters. "Our findings suggest that the biological significance of lack of sons - whatever it is that leads to increased risk of prostate cancer - becomes increasingly important as family size increases," said Dr. Harlap. "Overall, our findings are consistent with hypotheses that tie Y chromosome loci to prostate cancer, although other explanations cannot be excluded."

There also appeared to be a higher incidence of prostate cancer in men lacking daughters, although the figure was smaller. In men with two offspring, those with no daughters had an 11 percent increase compared with men who had one son and one daughter. "The increased risk of prostate cancer in men with no daughters is probably due to chance," speculates Dr. Harlap, "but it might indicate a problem with a gene on the X-chromosome."

Based on material from Columbia University's Mailman School of Public Health