Summary
In this section, we discussed information about genes that raise the risk for breast cancer in some families.
The main points addressed were as follows:
- Breast cancer is a relatively common disease, but only a small number of cases (5-10%) are thought to be caused by inherited gene mutations.
- Inherited susceptibility to breast cancer can be passed on from one's mother OR father, and can be passed to either a son or a daughter.
- Mutations in two genes, BRCA1 (Breast Cancer Gene 1) and BRCA2 (Breast Cancer Gene 2), account for the majority of breast and ovarian cancers that run in families.
- Having a mutation in either of the BRCA1 or BRCA2 genes significantly raises one's risk of breast cancer. These mutations also raise risks of ovarian and other types of cancer.
- Breast cancer can also occur as part of several rare cancer syndromes (e.g., Li-Fraumeni, Peutz-Jeghers) caused by gene mutations and passed on in families.
- Other genes are being identified that may raise one's risk of breast cancer, but these risks are much lower than the risks associated with BRCA1 or BRCA2.