With the ever-increasing popularity of personal genetic testing services, it may be no surprise that this year you’ve been gifted a mail-order genetic test.
Many direct-to-consumer genetic testing services allow you to trace your ancestry, but some companies now offer testing that can tell you if you are a carrier of an inherited condition or if you are at risk for developing a particular disease.
If you’ve been gifted a testing kit, it’s important to recognize that direct-to-consumer genetic testing, while fun, has major limitations.
“These tests are not used to make a diagnosis of a genetic condition,” says Erin Huggins, a genetic counselor at Tidelands Health Cancer Care Network at Murrells Inlet. “Nor do they provide information that should be used to make medical decisions.”
Genetic health risks
Genetic testing, whether done through a health care provider or a mail-order service, cannot tell you for certain if you will develop a specific disease.
“Genetic testing for a hereditary cancer condition will not tell you whether or not you will get cancer or whether or not you currently have cancer,” Huggins says. “But it may tell you if you have an increased risk for certain cancers.”
Furthermore, mail-order genetic testing examines a limited number of genetic variants. For example, the direct-to-consumer testing company 23andMe offers results for three variants in the BRCA1 and BRCA2 genes, but that only represents a small number of many mutations that are associated with an increased risk for breast and ovarian cancer.
Carrier status
Some direct-to-consumer services offer testing to determine if you are a carrier for a specific genetic condition, such as sickle cell anemia. Conditions like these are inherited in a recessive manner, meaning both parents must be carriers in order to have a child with the condition.
“Something that is inherited may be passed down from generation to generation,” Huggins says. “Because each individual’s genetic makeup is a combination of their mother’s and father’s DNA, there are several patterns in which a condition may be passed.”
Because these mail-order genetic testing services only test for a limited number of variants, they cannot tell you for certain that you do not carry a gene for a particular inherited condition.
Moreover, if you are a carrier, this does not mean that you will necessarily pass on the mutation.
Visiting a genetic counselor
Complex genetic information can be overwhelming and even frightening if not properly understood. If you receive a concerning result from a mail-order genetic testing service, you should consider visiting a genetic counselor.
Genetic counselors can test patients strategically and for many more variants than a mail-order genetic testing service. They are trained to order genetic testing from clinical laboratories that specialize in genetic testing in a medical setting, meaning that the information may be used to make medical decisions.
They can also provide detailed information on disease risk and talk to you about inheritance patterns to determine if your family members may be at risk for a certain inherited genetic condition.
Mail-order genetic tests are a great gift to give or receive but they should never be a substitute for seeing a trained medical professional. If you are concerned about your results from a genetic test or would like to know more about how genetic testing can help you make health decisions, talk with a genetic counselor, physician or other qualified medical provider.
