Investigating HCAR and FAN1 Variants as Inherited Risk Factors of Breast Cancer

Abstract

Inherited genetic risk factors in known breast cancer (BC) susceptibility genes increase an individual’s overall lifetime risk of developing BC but explain only ~35% of hereditary BC cases. Therefore, additional BC susceptibility genes and rare variants have been sought to decipher the remaining 65%, but have met with limited success. Low-frequency risk variants have not been thoroughly investigated for BC risk. Investigating this variant group in hereditary BC cases could provide insights to previously overlooked BC genetic risk factors. Moreover, African Americans have been sorely underrepresented in research, and are susceptible to health and healthcare disparities. Much less is known about African American hereditary BC genetics, thus, racial disparities must be addressed and efforts increased for the inclusion of African Americans in research studies. The AHCC (Alabama Hereditary Cancer Cohort) was established to study hereditary BC in underserved and underrepresented individuals in Alabama and bridge gaps in racial health and research participation disparities. In the research described herein, BC cases from the AHCC were screened to identify rare, pathogenic germline variants in HCAR1, HCAR2, and HCAR3 in European Americans and to investigate an African American-specific low-frequency variant in FAN1 that could be associated with hereditary BC risk.