Genetic Testing

What are genes?

Every cell in your body contains genetic material, or genes. Genes are the blueprints for your body. Sometimes, though, your genes do not work like they should. This is due to an error in one or more of your genes, called a mutation.

Mutations may be inherited or spontaneous. Inherited mutations are those you were born with — a defective gene that one of your parents passed on to you at birth. Spontaneous mutations are those that may occur in a single cell during the course of your life. There are many ways a spontaneous mutation can happen. However, scientists do not yet know exactly how, or if, these mutations are related to a women’s lifestyle (diet, exercise and reproductive patterns), chemical changes inside the body or exposure to environmental toxins such as radiation or chemicals — or if these mutations can even be prevented.

Genes and breast cancer

Scientists have found two specific genes that are important in the development of breast cancer. They are called BRCA1 and BRCA2. Every woman has these genes, but some women have inherited a mutated form of one or both genes. Inheriting a mutated form of BRCA1 or BRCA2 increases a women’s risk of breast and ovarian cancer. However, not all breast cancers are due to inherited mutations.

Inherited gene mutations, including mutations in BRCA1 and BRCA2, account for only about 5 to 10 percent of all cases of breast cancer, while most breast cancers are due to spontaneous gene mutations. Mutations in the BRCA genes are not only found in women. Men also carry the abnormal genes, which may increase their risk of prostate cancer. Men with a BRCA2 mutation also have an increased risk of breast cancer.

Who has mutations in BRCA1 and/or BRCA2?

The likelihood that you have mutations in the BRCA1 or BRCA2 genes is greater if one or more of the following statements is true for you:

• You are diagnosed with breast cancer at a young age (under age 50)
• Your mother, sister or daughter has had breast cancer before age 50 or ovarian cancer at any age
• A woman in your family has had both breast cancer and ovarian cancer
• A woman in your family has had breast cancer in both breasts
• Your family is of Ashkenazi Jewish descent
• There is male breast cancer in your family

Remember, most women who get breast cancer do not have an inherited gene mutation in BRCA1 or BRCA2. That is why it is important that every woman have mammograms as recommended, have clinical breast exams and perform monthly breast self-exams.