Intronic rs12505266 of CLOCK was significantly associated with an increased predisposition to breast cancer among recessive homozygous genotypes OR = 1.22 (0.83–1.79), p = 0.057 and at marginal significance under a recessive genetic model OR = 1.38 (0.97–1.96), p = 0.07.
has shown a highly significant association between the breast cancer risk and circadian pathway variation ( p -value 1.9 × 10 −6 ) The top genes and number of SNPs involved in cancer development were RORA and RORB (eight SNPs and five SNPs, respectively); other significant genes with single SNPs were PER1 (two SNPs), ARNTL , CRY2 , CLOCK , CRY1 , and RORC , in order of significance.