In UK Biobank, women with a BRCA1/2 variant are 1.5/1.9-times more likely to get breast cancer if they also have a first-degree family history of breast cancer, whilst individuals with a MLH1/MSH2/MSH6 variant are 2.3/2.5/1.4-times more likely to get colorectal cancer if they also have a first-degree family history of bowel cancer. Here, BRCA1 is linked to breast cancer.