The Genetics Of Breast Cancer
Every woman runs the risk of getting breast cancer and as she gets older, the chances are greater. The chances of a woman getting breast cancer is 14 percent or one in every eight women, when you consider a lifetime of a woman, assuming she lives up to the age of about 90 years. If you consider that in your lifetime of 90 years, the chances are 14 percent that you will get the disease. The good news is that 86 percent you will not get the disease.
How does genetics affect your chances of getting breast cancer?
Most of the inherited cases of breast cancer have been linked with the two genes Breast Cancer gene 1 (BRCA1) and Breast Cancer gene 2 (BRCA2). These two genes play a role in keeping the breast cells growing normally and preventing any cancerous cell growth. However, abnormal BRCA 1 and BRCA2 gene increase an individual’s risk from breast cancer. These genes usually account for almost up to 10 percent of all breast cancers.
Whilst a majority of women who get breast cancer have no family history of the disease, the women who are diagnosed with the disease and also have an abnormal BRCA1 or BRCA2 gene often are women with a family history of the disease.
These abnormal BRCA1 and BRCA2 genes can either be acquired or inherited. Acquired is non hereditary and the gene becomes abnormal as a result of an error in how the gene reproduces, wear and tear, exposure to toxic material, hormonal influence, diet, environmental factors or sometimes even unknown factors. Inherited from parent, that is one normal gene from one parent and one abnormal gene from the other parent. They are born with this abnormal gene. 85 percent to 90 percent of breast cancers are as a result of acquired genetic abnormalities.
The chances that an individual will have an abnormal breast cancer gene are:
. If a single individual in the family suffers from both ovarian and breast cancer.
. If on either the individual’s mother’s or father’s side sisters, aunts, mother or grandmothers have had breast cancer diagnosed before the age of 50.
. A male in the individual’s family has had breast cancer.
. The women in the individual’s family have had cancer in both their breasts.
. If the individual is from Eastern Europe.
If an individual’s mother or father has an abnormal breast cancer gene, the chances of the gene passing onto that individual is 50 percent. The chances of the individual passing it onto their children is 25 percent, provided the father does not have an abnormal gene. It does not necessarily mean that all family members will have an abnormal gene if one family member has it.
Men and breast cancer
Men are at an increased risk from breast cancer if they inherit the abnormal breast cancer genes. Over a man’s lifetime, the risk is about 6 percent, which is about 80 times more than for a man with no abnormal breast cancer genes.
Research has also shown that men who have an abnormal breast cancer gene are more likely to get prostate cancer than men who do not have it. This abnormal gene also has the same increased effect on cancer of the digestive tract or on cancer of the skin.