Breast cancer susceptibility genes

Five percent of all cases of breast cancer (BC) show a hereditary component related to gene mutations with an autosomic dominant transmission. To date, few genes are known to be responsible of hereditary BC. The germline mutations of BRCA1 or BRCA2 genes account for less than 50% of families with breast/ovarian cancer predisposition. The large percentage of families with multiple cases of female BC and no BRCA1 and BRCA2 mutations detected could be attributed to the existence of other high or low susceptibility genes acting together with lifestyle risk factors. The predisposition to BC in carriers of ATM mutations has been documented previously. Due to the frequency of ATM heterozygotes in the general population, the mutations in this gene could be associated with up to 5% of BC cases. The mutation 1100delC of the CHEK2 gene seems to be a low penetrance allele of BC susceptibility. The objective of the present manuscript is to review some of the susceptibility genes identified to date.