Methodist Healthcare - October 10, 2019

BRCA

Breast Cancer and Genetics

According to breastcancer.org, about 5% to 10% of breast cancers may be attributed to genes passed from a parent to a child. For women with one or more first-degree relatives (i.e. a mother, sister or daughter) who have had breast cancer, their risk of developing breast cancer doubles. Family history of ovarian cancer could also increase your risk of developing breast cancer. According to the National Cancer Institute, breast and ovarian cancers have been linked to two specific gene mutations: BRCA1 and BRCA2. Everyone has these two genes. They produce proteins that help repair damaged cells. However when these genes contain mutations and are passed from one generation to the next, they increase your odds of developing breast cancer.

Other factors that are also indicative of a possible genetic mutation include:

  • Family history of male breast cancer
  • Ashkenazi Jewish ethnicity
  • African American diagnosed with breast cancer at or before the age of 35
  • First-degree relative(s) breast cancer diagnosis before the age of 50
  • Personal history of breast cancer in both breasts
  • Multiple breast cancer diagnosis in the same side of the family
  • Family history of both breast and ovarian cancer
  • Two or more BRCA1 or BRCA2 related cancers within the same family

Methodist Healthcare System provides a description of breast cancer genetic testing.

Detecting BRCA1 and BRCA2 Genetic Mutations

If you determine you may be at risk of possessing BRCA1 or BRCA2 genetic mutations, speak to your doctor. He or she will help you identify the best test options for you. Since there are other genetic mutations that can occur, your doctor will determine if you need testing for BRCA1, BRCA2 or multigene panel testing. For women over 40, doctors recommend annual mammograms. Genetic testing is generally conducted by extracting DNA samples from blood or saliva. Results are generally returned within 30 days.