Is Hereditary Breast Cancer Common?
Genetic inheritance plays an important role in the development of breast cancer. About 10% of patients have inherited mutated genes. Patients with breast cancer gene mutations have a 10-fold higher chance of developing breast cancer. The most common genetic mutations in breast cancer occur in the BRCA 1 and BRCA 2 genes. When BRCA 1 & 2 mutates, it increases the risk of breast cancer or even other cancers, such as ovarian cancer and prostate cancer.
BRCA 1 & 2 gene mutations are inherited in an autosomal dominant manner, meaning if the child gets the abnormal gene from only one parent, the child will inherit the mutated gene and has a higher risk of getting cancer. Whether the BRCA gene mutation is found in a male or a female, it has a 50% chance of inheriting the BRCA 1 & 2 gene mutation to the next generation.
Does it mean I will get Breast Cancer if I have BRCA gene mutations?
To answer this question, we must first understand the role of BRCA genes. BRCA 1 and BRCA 2 are genes responsible for suppressing tumours. If BRCA 1 and BRCA 2 genes undergo genetic mutations, it means that they will not be able to suppress tumours and the risk of getting cancer will increase significantly.
Therefore, the detection of BRCA 1 & 2 gene mutation does not necessarily mean that you will get breast cancer. It means that people with BRCA 1 & 2 gene mutations have a higher risk of developing related cancers, such as breast cancer, ovarian cancer, and prostate cancer.
A well-known BRCA gene mutation carrier is the famous Hollywood movie star, Angelina Jolie. After considering the history of breast cancer in her family, she was tested for the BRCA1& 2 gene and found that she had inherited a BRCA gene mutation. She realized that her lifetime risk of breast cancer was as high as 87%, therefore, she decided to undertake a preventative double mastectomy.