Increasing numbers of hormones above the age- and batch-adjusted geometric mean level were linearly associated with total (RR per one-unit increase = 1.16, 95% CI = 1.08 to 1.24, P trend < 0.001) and ER-positive (comparable RR = 1.19, 95% CI = 1.09 to 1.29, P trend < 0.001) breast cancer risk (Table 2). The gene discussed is ESR1; the disease is breast cancer.