Scientists have discovered that a common genetic variant appears to increase the risk of prostate cancer in men who carry it. Specifically, it appears to confer a 60% greater risk of prostate cancer, and may also indicate a more aggressive cancer, when cancer occurs.
This discovery may also explain why African American men have higher rates of prostate cancer than others: This gene variation is about twice as common in blacks than it is in whites.
Kari Stefansson, CEO of deCODE ( www.decode.com) (the Icelandic company conducting the research), sums up why this discovery is so significant:
“This is one of the first genetic variants ever found to confer significant risk of a major cancer among the population in general. Most previously identified cancer genes have their effect on cancer risk only in families with a clear family history of cancer, or are only found mutated in tumors. This discovery is important from a medical standpoint because the only firmly established risk factors for the disease until now have been age, family history and ethnicity. As this variant also appears to be associated with the development of more aggressive prostate tumors, a diagnostic test for the variant may enable doctors to make more informed decisions as to how closely they should monitor those who are at high risk, and how aggressively they should treat the disease once it presents.”
P.S. Interestingly, it’s not clear whether the heightened cancer risk comes from the genetic variant itself or from another that lies nearby on chromosome 8. Sometimes genetic discovery is like that — the gene variant that scientists have discovered may just be a marker that travels along with the gene that’s actually causing the risk. (Prof. John Hawkes offers an evolutionary perspective on this.)