Take Charge

What’s in Your Genes?

November 14, 2019

Genetic Awareness Day

By Sara Bondell

Genetic counselors play an important role in health care, from helping you better understand genetic testing to identifying keys to family health history. Moffitt Cancer Center has six certified genetic counselors who can help decide if genetic testing is right for you, guide you through the process, interpret your test results and give you recommendations on screening and prevention.

What is genetic testing?
Genetic testing looks for changes, or mutations, in a person’s genes that can increase their risk for cancer. Inherited mutations account for 5% to 10% of all cancers. Knowing if you have an inherited cancer risk may offer options for cancer prevention, early detection and personalized treatment.

What does genetic counseling and testing involve?
During an appointment, one of our board-certified genetic counselors will meet with you to gather additional information about your personal health and family history of cancer, including a three-generation family history. They will discuss a number of factors with you, including the risks, benefits, limitations and emotional implications of testing, as well as insurance coverage and confidentiality. After discussing this information with your genetic counselor, you can decide whether you would like to move forward with genetic testing. If you decide to have genetic testing, a blood or saliva sample will be collected and test results are typically ready within three to four weeks. You and your genetic counselor will review these results together. Genetic counseling and testing may provide opportunities for risk reduction, early detection or targeted treatment for yourself and family members.

What are the different types of genetic testing?

  • Pharmacogenetic testingcan identify genetic differences that affect your response to certain drugs. 
  • Ancestry Genetic Testingis available outside of a physician’s office and can help identify certain information about your ethnicity and where your ancestors came from.
  • Carrier Genetic Testingis often pursued by couples planning on having children together who may have a family history of or are at increased risk for specific genetic conditions (i.e., Cystic Fibrosis or Sickle Cell Disease)
  • Somatic Tumor Testingis ordered by a physician, and is performed on tumor tissue to look at the genetic makeup of a tumor. This testing can sometimes help determine which treatments may be most effective.
  • Germline Genetic Testingis a tool to help determine if someone has a specific condition or is at increased risk to develop certain types of cancer. Germline genetic testing for inherited cancer risk looks at the genetic makeup that you were born with and is ordered in the context of a genetic counseling session. In a genetic counseling session, you meet with a genetic counselor who is specifically trained to help you understand your cancer risks based on family history, whether genetic testing is right for you, and what genetic testing could mean for you and your family. 

Should I consider genetic testing?
You can gauge your risk for an inherited cancer gene by looking at your personal and family history. There are some features that may be present in a family that would make an inherited cancer risk more likely. These include:

  • Cancer in two or more generations
  • Two or more people on the same side of the family with the same type of cancer
  • A family member with more than one type of cancer
  • Family members diagnosed with cancer at a young age (generally younger than age 50)
  • A family member with a rare type of cancer, like ovarian cancer
  • Certain ethnic backgrounds, like Ashkenazi Jewish ancestry, in which inherited cancer risk may be more common

It’s important to note particular cancers may have strong associations with other risk factors aside from genetics. For example, lung cancers diagnosed in individuals who use tobacco products or smoke or cervical cancer in individuals who have exposure to the human papillomavirus (HPV).

Genetic counseling and testing may also be a good option if you’ve already been diagnosed with cancer, especially if there are particular factors to suggest the cancer may be caused by an inherited genetic mutation. Testing can show if you are at risk for other cancers and if other members of your family should be tested.