Angelina Jolie has had a double mastectomy after doctors calculated she had an 87% chance of developing breast cancer as a carrier of the BRCA1 gene.
- Around 1 in 20 breast cancers is partly caused by an inherited gene fault and the BRCA1 gene is just one of these.
- The BRCA1 gene helps to repair damage to DNA. When a mutated gene is passed from parent to child, all the breasts' cells carry this mutation.
- Women with a faulty gene have a 50 to 80% chance of getting breast cancer in their lifetime.
- BRCA2 and TP53 genes are also associated with increased risk of breast cancer.
- Genetic tests are available to women with a high risk of having changes in these genes.
Brad Pitt described his partner Angelina Jolie as "absolutely heroic" after the actress revealed she underwent a double mastectomy.
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As Angelina Jolie reveals she underwent a preventative double mastectomy, Tracey Barraclough tells ITV News why she had the same procedure.