A genome-wide associations study (GWAS) of the Single-nucleotide polymorphisms (SNPs) in HMGCR found that genetically proxied inhibition of HMG-CoA reductase was significantly associated with a reduced risk of breast cancer (OR 0.84; 95% CI 0.74–0.95; p = 0.005), thus variants leading to the inhibition of HMG-CoA reductase lowered the probability to develop breast cancer. The gene discussed is HMGCR; the disease is breast cancer.