578 Background: Premature ovarian failure and accelerated bone loss are common late effects of adjuvant chemotherapy for breast cancer. Polymorphisms (SNPs) in bone metabolism and estrogen biosynthesis genes associated with osteoporosis in the general population have been identified (COL1A1 Sp1, IL6_634, VDR fok1 & taq1, ESR1_397, ESR1_325, ESR Xba1, TGF-B 509 & 869). Little is known about clinical and genetic risk factors for osteoporosis in breast cancer survivors. Methods: We performed a cohort study at the Abramson Cancer Center of the University of Pennsylvania. Eligible patients were female, premenopausal at breast cancer diagnosis, AJCC stage I, II or III, had recent follow-up with no recurrence, and received adjuvant chemo one to four years prior to enrollment. Subjects signed informed consent, completed questionnaires, provided blood samples for genomic DNA, and underwent bone density measurement via DEXA scan as part of usual clinical care. Single nucleotide polymorphisms were identified via pyr...