How race to track mystery gene with links to three cancers saved millions

25 years ago, a mutation was discovered that makes some people susceptible to the disease, and now it has transformed treatment

Ten years ago, Tony Herbert developed a lump on the right side of his chest. The clump of tissue grew and became painful and he was tested for breast cancer. The result was positive.

I had surgery and chemotherapy and that worked," he said last week. But how had Herbert managed to develop a condition that is so rare in men? Only about 400 cases of male breast cancer are diagnosed every year in the UK compared with around 55,000 in women. A genetic test revealed the answer. Herbert had inherited a pathogenic version of a gene called BRCA2 and this mutation had triggered his condition.