Seven new genetic variants associated with prostate cancer have been identified, reports a study in  Nature Genetics. The study brings the number of prostate cancer susceptibility loci that are known to  over 40.

Prostate cancer often clusters in families and it is estimated that 5 to 10% of all prostate cancers may have a substantial inherited component.

Rosalind Eeles and Colleagues, from the Institute of Cancer Research (Sutton, Surrey, UK),  undertook a multi-stage genome-wide association study for prostate cancer in 4,574 cancer cases and 4,164 controls. In addition to replicating previously reported loci, the team identified seven new prostate cancer susceptibility loci on chromosomes 2p11, 3q23, 3q26, 5p12, 6p21, 12q13 and Xq12.

Based on an overall two fold familial relative risk to first-degree relatives of prostate case cases, and the assumption that SNPs combine multiplicatively, the authors estimate that the new loci will explain approximately 1.5% of the familial risk of prostate cancer. When added to  previously reported loci  approximately 25% of the familial risk in prostate cancer can now  be explained.

“Under this model, the top 10% of the population at highest risk has a relative risk approximately 2.4 fold greater than the average risk in the general population, and the top 1% has an estimated 4.1-fold increased relative risk,” write the authors, adding that such risk prediction could in future become important for facilitating both targeted screening and prevention programmes.

Reference

Z Kote-Jarai, A Al Olama, G Giles, et al.  Seven prostate cancer susceptibility loci identified by a multi-stage genome-wide association study. Nature Genetics. doi:10.1038/ng.882