At-Home Genetic Tests for Cancer: What You Need to Know

At-home genetic testing, also called direct-to-consumer genetic testing, has become a popular way for people to learn about their ancestry and family lineage. More recently, at-home genetic tests that claim to determine a person’s potential risk for health conditions, such as cancer, heart disease, and Alzheimer’s disease, have become available.

Here, Sarah Cochrane, MS, LGC, a genetic counselor at Dana-Farber Cancer Institute, answers some questions you may have about the benefits and limitations of at-home genetic testing.

What are at-home genetic tests and how do they test for cancer risk?

At-home genetic tests provide people with a way to receive genetic testing without seeing a medical professional. Companies that sell these at-home genetic tests will often mail a saliva kit to the consumer. In the past, people used these tests to learn more about their ancestry, but people now are increasingly interested in using them to test for breast and ovarian cancer risk in particular.

However, the ability of at-home genetic tests to provide information about your cancer risk is very limited. This testing can now identify whether or not a person carries one of the three common Ashkenazi Jewish founder mutations in the BRCA1 and BRCA2 genes. Therefore, these at-home tests are really only helpful for people with Ashkenazi Jewish heritage, who are more likely to have a harmful mutation in the BRCA1 and BRCA2 genes than patients of other ancestries. Even in patients with Ashkenazi Jewish descent, additional genetic testing (beyond at-home genetic testing) can be useful, given that some Ashkenazi Jewish patients harbor a mutation elsewhere in one of the genes, or in a different gene that would not be assessed through at-home genetic testing.

Companies that sell at-home genetic tests will often mail a saliva kit to the consumer, which can then be analyzed.
Companies that sell at-home genetic tests will often mail a saliva kit to the consumer, which can then be analyzed.

What do people hope to learn from these tests? Do they offer satisfactory answers?

People who purchase at-home genetic tests are often trying to learn about their health risks to be proactive about preventative measures they can take to potentially reduce this risk. However, at-home genetic tests do not provide conclusive answers to questions about cancer risk. People looking to learn about their personal cancer risk and methods to reduce this risk should meet with a healthcare provider, such as a genetic counselor to discuss comprehensive cancer genetic testing.

Are there any problems or concerns with at-home genetic tests?

The biggest problem and concern with at-home genetic tests is that the results can provide people with false hope and false reassurance about their cancer risk. People may believe that a negative test result means they are “off the hook” for cancer risk, but this is not necessarily the case.

Do genetic counselors recommend at-home genetic testing?

At this time, at-home genetic tests are not recommended as a health or cancer risk test. It is possible that the technology will improve in the future making the tests more conclusive and comprehensive, but for now, they work well for ancestry and recreational purposes, and not for cancer risk assessment. Patients wanting a test to help make clinical or cancer risk decisions should talk to their doctors or a genetic counselor about clinical genetic testing.

What should someone do if they receive a worrisome result on an at home genetic test?

People who believe they may have a heightened cancer risk based on at-home genetic test results should see a genetic counselor for confirmatory testing and a discussion of cancer risks. Those local to Boston can visit Dana-Farber’s Center for Cancer Genetics and Prevention. A genetic counselor in other parts of the country can be found through the National Society of Genetic Counselors “Find a Genetic Counselor” tool.

Learn more about genetic testing from Dana-Farber Cancer Institute.