ERBB2 and breast cancer: Genetically proxied smaller comparative body size at age 10 was likewise associated with lower risk of overall (OR:0.62, 95% CI:0.55–0.70, p = 8.25−14), luminal A-like (OR:0.65, 95% CI:0.55–0.74, p = 2.19x10−8), and luminal B HER2 negative-like breast cancer risk (OR:0.63, 95% CI:0.52–0.76, p = 1.87x10−6) (Figure 5, Table S6).