What is a BRCA mutation?
The BRCA gene (Breast Cancer gene) encodes a tumour suppressor gene in a healthy state. This is a protein that suppresses the uncontrolled division of cells and thus prevents malignant degeneration of the cell into a tumour. If a mutation occurs in this gene, the affected BRCA gene carriers have a significantly increased risk of developing breast cancer (breast carcinoma) or ovarian cancer (ovarian cancer) during their lifetime. There are two BRCA genes: BRCA1 and BRCA2. It is assumed that about 5% of all breast cancers are caused by a BRCA mutation and are therefore hereditary.
What is a BRCA1 gene?
BRCA1 (Breast Cancer gene 1) is a gene from the group of tumour suppressor genes (“tumour suppressing genes”). BRCA1 is located in the genome on chromosome 17, where it codes for proteins that protect against tumour development. The exact function of the BRCA1 gene product is to repair damage (so-called double-strand breaks) in the human genome, the DNA. Due to certain mutations, the gene may no longer function at all or only to a limited extent (loss-of-function mutation or deletion), which increases the probability of the affected cell degenerating into a malignant tumour.
What is a BRCA2 gene?
BRCA2 (Breat Cancer gene 2) was discovered a few years after BRCA1. The gene is located on chromosome 13. This gene also codes in the cell for a tumour-suppressing protein that plays a decisive role in the repair of DNA damage.
Mutations in BRCA2 prevent these repair processes and thus increase the risk of certain cancers, especially breast or ovarian cancer. Are you more interested in this topic? mutated BRCA1 and BRCA2 are both among the high-risk genes for breast and ovarian cancer.
In an intact state, the products of these genes counteract tumor development, although the exact function of both genes is not yet fully understood. The genes are located on different chromosomes in the genome. A mutation in BRCA1 or in BRCA2 increases the likelihood of the affected woman developing breast cancer and the probability that she will develop breast cancer up to the age of 70 is up to 80%. In addition, a BCRA1 mutation significantly increases the risk of ovarian cancer (50% chance of developing the disease), whereas the risk of developing this disease is also increased with a BRCA2 mutation, but the probability of developing the disease is lower and is only 30-40%.
Can I tell from certain symptoms that I suffer from a BRCA mutation?
A BRCA mutation does not cause symptoms by which the gene change can be recognized. People with mutated BRCA genes are not ill, but they simply have a significantly increased risk of developing breast or ovarian cancer later in life. The only indication of hereditary breast cancer is a family history of breast cancer. You can read more detailed information on this topic here: Symptoms of Breast Cancer
