BRCA1 and neoplasm: In one study investigating the relationship between breast and ovarian cancer predisposition and germline and somatic variants of MUTYH, OGG1, and BRCA1, 18 variants (including four novel ones) were identified, and a strong correlation between MUTYH and OGG1 expression was observed in tumor tissue but not in controls, suggesting coordinated BER pathway dysregulation [34].