ESR1 and breast cancer: For CALM2, ORs for SNP rs13032512, with a risk-allele frequency of 5.5% in AMBER controls, were 1.33 (P=1.3×10−4), 1.30 (P=4.1×10−3), and 1.35 (P=8.2×10−3) for overall, ER+, and ER− breast cancer, respectively.