The specific aims of the Center for Interdisciplinary Health Disparities Research are to: Aim #1: bring together scientists from inside and outside the University and members of the community who are especially vulnerable to adverse health conditions to inform the Center's scientific agenda; Aim #2: foster investigations that consider health disparities from multiple levels of analysis via shared conceptual frameworks that integrate discipline-specific theories and methods; Aim #3: increase interest in health disparities among scientist and students from various disciplines and from community members; Aim #4: develop measures and methods that are appropriate for use with vulnerable populations and that allow factors at various levels (social/environmental, behavioral/psychological, and biological/genetic) to be analyzed together; Aim #5: increase existing knowledge on the social, behavioral, and biological factors that influence health disparities and the nature of their interactions; and, Aim #6: disseminate findings through channels established through the Center to as wide an audience as possible, including members of vulnerable populations, community-based organizations and agencies, and scientific investigators inside and outside the University. In its first five years, the Center will focus on group differences in breast cancer, notably why Black women in the US and West Africa experience breast cancers that occur at a younger age and are more aggressive and lethal than those of White women. McClintock (R01 # 1), based on an animal model of social regulation of mammary tumor biology developed in her laboratory, will compare the gene regulation in mammary tumors and the ovarian function of socially isolated and group-living rats. OIopade (R01# 2) will (a) look at the molecular characterization of primary patient samples in Nigeria and Chicago's South Side to see if alterations in BRCA1 contribute to breast cancer in younger Black women and (b) explore the McClintock model in primary patient samples. Gehlert and Masi (R01# 3; CBPR) will explore emic views of breast cancer and its treatment and test the McClintock model with community volunteers. In the lalffer, they will examine neighborhood and community factors (such as collective efficacy and crime), living situations and social connectedness, behavioral responses (such as vigilance and perceived stress), and biological (e.g., cortisol levels) and health outcomes (most notably breast cancer). Conzen (R01# 4) will study rate of mammary tumor growth, response to chemotherapy, and chemoprevention in two animal models. The Tissue Core will provide analysis of mammary tissue. Coordination and dissemination will occur through the Administrative Core, by means of Faculty Colloquium and Monthly Speaker Series, In-Service and Summer Apprenticeship programs, a Center Web site and Web page for communication with other CPHHDs, etc.