To achieve these objectives, NCI will initially work with fresh specimens that are being prospectively collected under the University of Massachusetts IRB-approved open protocol entitled Epigenetics and Breast Cancer Risk in African American Women , funded by the Avon Foundation for Women. Dr. Arcaro s lab is studying breast cancer risk and promoter hypermethylation in breast cells obtained from the milk of nursing women. They have analyzed breast cells from nearly 400 women and are continuing with long-term follow-up. However, the majority of the data has been from White women. Since disease risk factors differ between ethnic groups, it is important to test risk assessment methods on a wide population. The main purpose of this specific UMass study is to extend their findings of breast cancer risk to African American women. They plan to recruit 200 lactating African American women to participate in the breast milk study. This involves collecting questionnaire data, completing methylation analyses for eight genes, archiving milk and the remaining DNA for future studies, and annual follow-up.