Early menstruation, late menopause, no pregnancy, and genetic factors are known risk factors of the disease, but their effects may differ in Asian and Caucasian women. The purpose of this study was to identify genetic variants of genes related to estrogen signaling in a large city hospital-based cohort and to determine their interactions with lifestyles.
This is a case-control study. Three hundred ninety participants diagnosed with breast cancer were compared with 36,290 controls(no cancer)to explore the genetic variants to influence breast cancer risk. Based on GWAS results, the selected genetic variants were subjected to their interactions by generalized multifactor dimensionality reduction (GMDR) analysis.
Early menstruation(OR=1.55), early menopause (OR=1.70), and no experience of pregnancy(OR=2.86) had a positive association with breast cancer risk(P<0.05). The selected polygenetic risk score(PRS) models included four SNPs and seven SNPs: The four-SNP PRS model included CDH13_rs12600325, SMYD3_rs3753686, FGF12_rs2134635, and ESRRB_rs10873289, and in the seven-SNP PRS model, ESR1_ rs2046210, estrogen-related receptor gamma(ESRRG)_rs17043393, and EGFR_ rs6958497 were added into the four-SNP PRS model. Early menstruation, early menopause, and no pregnancy experience interacted with four-SNP PRS. For the participants who had early menstruation and early menopause, high-PRS had an association with a much higher breast cancer risk than the low-PRS in the four-SNP model. However, metabolic parameters, nutrient intakes, and different dietary patterns did not interact with PRS for breast cancer risk. However, alcohol intake interacted with PRS for breast cancer risk (OR=2.33 and 8.07 for mild and moderate alcohol consumption, respectively; P=0.0004).