To create their panel, the scientists chose the best SNPs from each of the five regions and tested their cumulative effect on prostate cancer risk. As the number of associated SNPs increased, so did risk. Men with four or more of these SNPs were nearly 4.5 times more likely to have prostate cancer.
This work strongly suggests that because of the combination of polymorphisms we inherit, one man may be more on the path to developing prostate cancer than another, says Isaacs, who is the William Thomas Gerrard, Mario Anthony Duhon and Jennifer and John Chalsty Professor of Urology at the Brady Urological Institute and professor of oncology at the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins.
Add to that a family history of prostate cancer and the risk doubles. Men with all five SNPs plus a family history of prostate cancer were nearly 9.5 times more likely to have the disease. Further analysis revealed that 46 percent of prostate cancer cases in this population were due to these risk factors. But the scientists estimate that almost 90 percent of the Swedish population carries one or more of the five SNPs, elevating their risk for prostate cancer relative to men who carry none of these factors.
Swedish populations are relatively homogenous, tending to marry other Swedes and well suited for such genetic studies because genetic variation is somewhat more limited than in larger, heterogeneous groups. Socialized medicine in Sweden also enables access to robust registries of patient data.
In addition, Swedes suffer from higher-grade prostate and other cancers, and deaths among their Cauca
|Contact: Vanessa Wasta|
Johns Hopkins Medical Institutions