Mutations of the MYH gene do not substantially contribute to the risk of breast cancer

Purpose To explore whether or not there is an association between the presence of either of the germline mutations in the MutY human homologue (MYH) gene (Y165C and G382D) and the risk of breast cancer. Methods 691 breast cancer patients and 812 healthy controls were genotyped for the MYH Y165C and G382D mutations. The frequencies of heterozygotes, homozygotes and compound heterozygotes were compared for the two groups. Results Four (0.6%) of 691 breast cancer cases carried a MYH Y165C mutant allele, compared to five (0.6%) of the controls (OR 1.1, 95%CI 0.29–4.0, P = 0.9). Eight (1.2%) cases carried a MYH G382D mutant allele, compared to eight (1.0%) of the controls (OR 1.2, 95%CI 0.44–3.3, P = 0.7). No case or control was homozygous for the variant and none were compound heterozygotes. Conclusion Carriers of the MYH Y165C or G382D mutant alleles do not appear to be at increased risk for breast cancer.