BRCA2 and breast cancer: However, we cannot rule out the possibility that some variants are risk-associated since the power for detecting an association with risk for PALB2 is lower than, for example, BRCA1 and BRCA2. One variant in BRCA1 (p.Arg841Trp) was individually associated with a reduced risk of breast cancer (0.67 (0.52–0.87)).