By examining DNA from 2,893 men with prostate cancer and 1,781 healthy control subjects, all from Sweden, scientists have found five genetic variations that dramatically raise the risk of the disease. When combined with family history, they accounted for almost half of all cases of prostate cancer in Swedish men.
On their own, none of the five did much to raise prostate cancer risk. However, combinations of them did. Men with four of the five genetic variants were more than four times as likely to develop prostate cancer than those with none of the markers. Men with at least four of the five markers and a family history of the disease were more than nine times as likely to develop the disease.
Interestingly, the combination of genetic variants did not correlate with levels of prostate-specific antigen (PSA), the substance measured during current screening tests for prostate cancer. Nor did they have anything to do with the aggressiveness of the cancer. But if the findings can be replicated in a more heterogeneous population, researchers could create a blood test to predict who might develop the disease.
SOURCE: Zheng SL, Sun J, Wiklund F, et al. Cumulative Association of Five Genetic Variants with Prostate Cancer. The New England Journal of Medicine 2008;358:910–19. PMID: 18199855.
Originally published April 2009; last reviewed February 24, 2011.