Breast Cancer, Breast Density & Admixture Among Latinas

Grant #: 5K22CA109351-03
RFA/PA: PAR01-134
PI Name: Ziv, Elad
Title: Breast Cancer, Breast Density & Admixture Among Latinas
Institute: University Of California San Francisco
Funding Started: 8/20/2004

Breast cancer incidence and mortality vary substantially among different racial and ethnic groups in the United States. Caucasian women have the highest incidence of breast cancer, while Native American women are reported to have the lowest incidence and mortality from breast cancer. Latinas, an admixed population of mixed European Native American and African descent, have an incidence of breast cancer that is higher than Native Americans but lower than Caucasians in the United States. In the San Francisco Bay Area, the majority of Latinas are from Mexico and are mostly of European and Native American descent. Thus, the rate of breast cancer among Latinas is consistent with their mixed ancestry. While these differences may be at least partially due to reproductive, lifestyle or other environmental differences between these groups, the investigators hypothesize that these differences are at least partially due to genetic differences between these groups. In particular, they hypothesize that Latinas with higher European ancestry are at increased risk of breast cancer. To test this hypothesis, they propose to study genetic ancestry among Latinas in relation to breast cancer risk and in relation to breast density, a strong risk factor for breast cancer. In particular, they propose the following specific aims:

1. To compare the genetic ancestry of 240 Latina breast cancer cases with 300 age-matched Latina controls and determine if genetic ancestry among Latinas is a risk factor independent of known environmental risk factors for breast cancer. This aim will be completed with existing blood samples.
2. To compare the genetic ancestry of 100 Latina women with extremely high breast density to 100 Latina women with extremely low breast density and determine if genetic ancestry among Latinas is associated with increased mammographic density independently of known environmental risk factors. This aim will be completed with a new sample collection.