In the subjects with three night shifts, SNPs in BMAL1 (rs2278749), BMAL2 (rs2306074), CSNK1E (rs5757037), NPAS2 (rs17024926), PER3 (rs1012477) and MTNR1A (rs131113549) were associated with decreased breast cancer risk. Here, BMAL2 is linked to breast carcinoma.