Susceptibility genes involved in disease etiology and prognosis are categorized into two groups: high penetrance genes (i.e., BRCA1, CHEK2, ATM, etc.) and low penetrance genes (i.e., NATs, GSTs, CYPs, etc., and variants identified by genome-wide association studies). Since low penetrance genes have high population attributable risk, the usefulness of those genes to research on breast cancer prevention is not small. In this chapter, the previous studies on low-penetrance genetic susceptibility through a candidate gene approach and genome-wide association of breast cancer were summarized. The contribution of low-penetrance susceptibility genes to the breast cancer risk prediction models will also be discussed on the utility in clinical or public health application.
Keywords: Genetic susceptibility; Genome-wide association study; High-penetrance genes; Low-penetrance genes; Polygenic risk score; Prediction model; Risk assessment.