BRCA1/2 Mutations May Decrease Lifespan Even In The Absence of Cancer
March 13, 2009
PLoS ONE, suggests that those BRCA1/2 carriers who do escape cancer may still be at risk of a shorter than average lifespan.In a study of almost 5,300 people with Ashkenazi Jewish ancestry researchers found that, on average, both men and women who carry BRCA1/2 mutations die younger — even when cancer deaths are excluded from the analysis. Among women free of melanoma, breast, ovarian and pancreatic cancer, BRCA1/2 mutation carriers died 5.8 years earlier (age 75.0 vs. 80.5) than those women without the mutations. In men, after excluding cases of melanoma, prostate and pancreatic cancer, BRCA1/2 mutation carriers died about 3.7 years earlier than those without the mutations (71.0 years old vs. 74.7).“Theoretically, these mutations may either be associated with a small increase in risk of a variety of different diseases, or they may be associated with moderate increase in risk of a few major diseases,” the authors write. They note that the current study is unable to make this distinction because it did not collect information on non-cancer related causes of death.The researchers analyzed the effects of only the three BRCA mutations that are most common in Ashkenazi Jewish people: 185delAG in BRCA1, 5382insC in BRCA1, and 6174delT in BRCA2. The mutations account for 80-90% of hereditary breast and ovarian cancer in this ethnic group. But there are hundreds of other BRCA1/2 mutations that have been associated with cancer, and the authors caution that further studies taking these other BRCA1/2 mutations into account and using study subjects from diverse groups will be needed to confirm their results.(23andMe provides data for the three BRCA1/2 mutations most commonly found in people with Ashkenazi Jewish ancestry in the BRCA Cancer Mutations (Selected) Carrier Status Clinical Report.)The authors conclude that understanding the effects of BRCA1/2 mutations on non-cancer related deaths could eventually help scientists understand how the mutations affect cancer risk and may even facilitate efforts aimed at finding new ways of preventing disease in BRCA1/2 mutation carriers.