According to the results of a study published in the Journal of the American Medical Association, rates of BRCA1 mutations among U.S. breast cancer patients are higher among Hispanic women than among African-American or Asian-American women.
Inherited mutations in two genes-BRCA1 and BRCA2-have been found to greatly increase the lifetime risk of developing breast and ovarian cancer. Alterations in these genes can be passed down through either the mother's or the father's side of the family.
BRCA1 and BRCA2 mutations are more common in some ethnic groups. The frequency among people of Ashkenazi Jewish descent, for example, has been reported to be higher than the frequency among the non-Ashkenazi, non-Hispanic White population. Less information has been available about the frequency of BRCA1 or BRCA2 mutations in other racial and ethnic groups.
To evaluate the frequency of BRCA1 mutations among five U.S. racial and ethnic groups, researchers conducted a study among breast cancer patients under the age of 65. The patients were registered with the Northern California site of the Breast Cancer Family Registry.
The study included 549 non-Hispanic White patients, 444 Asian-American patients, 393 Hispanic patients, and 341 African-American patients.
- BRCA1 mutations were identified in 3.5% of the Hispanic patients, 1.3% of the African-American patients, 0.5% of the Asian-American patients, 8.3% of the Ashkenazi Jewish patients, and 2.2% of the non-Ashkenazi, non-Hispanic White patients.
- In all racial and ethnic groups, the frequency of BRCA1 mutations was higher among younger patients. The frequency was particularly high among young African-American patients. Among African-American breast cancer patients under the age of 35, 17% had a BRCA1 mutation.
This study suggests that overall, BRCA1 mutations are more common among Hispanic breast cancer patients than among African-American or Asian-American breast cancer patients. Subsequent analyses will evaluate the frequency of BRCA2 mutations in these groups.
These results may help guide the use of genetic testing to identify BRCA1 and BRCA2 mutations. Women who are found to have a BRCA1 or BRCA2 mutation may be candidates for preventive surgery, use of medications to reduce cancer risk, or more intensive cancer screening.
Reference: 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.