A variety of cancer related self-tests are available to buy by members of the UK public, including tests for faecal occult blood [36], prostate specific antigen [37], haematuria [38], serum α-Fetoprotein and serum carcinoembryonic antigen (CEA) [39], and breast cancer self-examination kits [40]. This evidence concerns the gene KLK3 and breast carcinoma.