ATM and ovarian carcinoma: ATM c.146C>G (p.S49C) was detected in families RF6 and RF20; its associated breast cancer risk is unlikely to be larger than 1.5.34, 36, 37 Likewise, conflicting results were obtained for the breast and/or ovarian cancer risk of RAD51C c.790G>A (p.G264S) in families RF8 and RF19.38