In premenopausal BRCA1 mutation carriers, significantly lower serum HE4 levels were observed in comparison to patients with ovarian cancer (P = 0.0000), other gynecological cancers (P = 0.0002), uterine myomas (P = 0.0021), noncancer ovarian cysts (P = 0.0000), and adnexitis (P = 0.0035). The gene discussed is BRCA1; the disease is ovarian cancer.