CYP19A1 and breast cancer: Furthermore, Henry et al. [36] analyzed 138 variants in 24 genes (including 23 CYP19A1 SNPs) in 432 BC patients and observed a non-significant increase in MS-AEs when at least eight rs60271534 repeat alleles were present (HR, 1.8 [95 % CI, 0.8–1.8], P = 0.49).