• Two or more women in different generations on the same side of the family had breast or ovarian cancer.
• A woman in the family has had both breast and ovarian cancer, or was diagnosed with breast cancer in either breast two or more times.
• A man in the family has breast cancer.
Families of Ashkenazi Jewish ancestry may also be at risk of an inherited mutation if there is a history of ovarian or pancreatic cancer or breast cancer in a man or woman in the family.
Genetic mutations in the BRCA genes can occur in both men and women. The mutation can be present in someone who develops cancer. But someone who does not have cancer can also carry the gene and pass it on to his or her children.
If your mother or father have a harmful BRCA mutation, you and each of your brothers and sisters have a 50/50 chance that you will inherit the mutation.
Every person inherits one BRCA1 and BRCA2 gene from each of his or her mother and father. If either copy of the BRCA genes is damaged, the risk of cancer is increased even if the second copy of the gene from your other parent is normal.
If you inherit a harmful copy of the BRCA genes, your risk of developing breast and/or ovarian cancer is significantly higher than normal.
In general, about 12 percent of all women will develop breast cancer. But 55 to 65 percent of all women who have a harmful BRCA1 mutation, and about 45 percent of women with a harmful BRCA2 mutation, will develop breast cancer by the age of 70, reported the National Cancer Institute.
Approximately 1.3 percent of all women will develop ovarian cancer. However, 39 percent of women with a harmful BRCA1 mutation and up to 17 percent of women with a harmful BRCA2 mutation will develop ovarian cancer.
Men with the BRCA mutation are also at increased risk of breast and prostate cancers.
Genetic testing can make it possible for a person with a probable family history of BRCA mutation to find out whether his or her own genes are normal, or if he or she carries the mutation.
Blood and saliva tests are available to check for mutations in the BRCA1 and BRCA2 genes.