Encodes protein that interacts with the N-terminal of BRCA1. Shares homology with the two most conserved regions of BRCA1, the N-terminal RING motif and the C-terminal BRCT domain. The RING motif is typically found in proteins that regulate cell growth. The protein encoded by BARD1 may be the target of oncogenic mutations that are found in breast and ovarian cancer. Here, BARD1 is linked to ovarian cancer.