BRCA1 mutations most common in these ethnic groups

A survey of BRCA1 mutation carriers among ethnic populations found the highest prevalence among Ashkenazi Jews followed by Hispanics and the lowest prevalence in Asian Americans, researchers report in the Dec. 26 issue of the Journal of the American Medical Association.

Esther M. John, PhD, of the Northern California Cancer Center in Fremont, CA., and colleagues recruited breast cancer patients younger than 65 into a family registry using a two-stage sampling design with oversampling of patients having characteristics suggesting their cancers might be inherited. Race and ethnicity were self-identified and participants provided a biospecimen sample for BRCA1 mutation testing.

The prevalence among Ashkenazi Jews was 8.3%. In patients without Ashkenazi Jewish ancestry, estimated mutation prevalence was highest in Hispanics (3.5%), followed by non-Hispanic whites (2.2%), African-Americans (1.3%), and Asian-Americans (0.5%). The most common mutation seen in Hispanics was 185delAG. "The higher carrier prevalence in Hispanics may reflect the presence of unrecognized Jewish ancestry in this population," the authors conclude.

John EM, Miron A, Gong G, et al. Prevalence of pathogenic BRCA1 mutation carriers in 5 US racial/ethnic groups. JAMA. 2007;298:2869-2876.