Genetic Counseling vs. 23andMe: What’s the difference?

Before you order that at-home genetic testing kit…

Content authored by: Ann Faulkner, Licensed Genetic Counselor, Thompson Cancer Survival Center

Genetic testing is more accessible than ever with the advent of direct-to-consumer testing like 23andMe. But what are the benefits of seeing a genetic counselor rather than ordering the test yourself?

Direct-to-consumer (DTC) companies such as 23andMe, AncestryDNA, or CircleDNA, offer genetic testing that can be done from the comfort of your own home. The availability and convenience of these tests make them a popular option for people interested in what their genes can tell them about their ancestry and their health. Genetic counselors offer a similar service; genetic counselors facilitate genetic testing for patients interested in knowing their risk of developing hereditary cancers.

With so many options for genetic testing, how can you determine what type is best for you? Why should you see a genetic counselor instead of ordering a genetic test online?

Before the Test

Choosing a test online is just like any other type of online shopping. Add the test to your cart, put in payment information, and wait for it to show up at your door. The websites may provide short descriptions of the information that the test can report back, but the consumer typically has to do a little more digging if they want more information. If someone has questions about the test they are interested in, they may have to search for the answer themselves or find contact information to directly contact the company.

When meeting with a genetic counselor, you can expect to receive more information about the testing being performed. A genetic counseling appointment includes many different components. The genetic counselor will ask questions about the patient’s personal health history and family history of cancer. This information can help the genetic counselor to provide a personalized risk assessment for the patient. For example, they may be able to provide the patient with the chances that they will develop breast cancer over their lifetime or estimate the chances that there is a hereditary cancer predisposition running through the family. The genetic counselor will also provide a brief overview of the purpose of testing, how testing works, and the types of results that could come back. This counseling before testing is meant to give patients comprehensive information that may be used to make decisions about genetic testing as well as give an opportunity to have questions answered. After the conversation about the testing process, the genetic counselor will help patients decide which test is right for them and their families.

The Test Itself

Think of DNA as an instruction manual for how to build a person. Our DNA has its own alphabet that spells out these sets of instructions; when there are “typos” in this instruction manual, called mutations, the body can’t read that set of instructions anymore. Occasionally, those instructions are meant to protect us from diseases like cancer. We want these instructions to be spelled correctly so that they can do their jobs properly.

Companies like 23andMe use a technology called an SNP array that looks at specific letters in the body’s instruction manual (DNA). They search the instructions for the more common “typos,” but they aren’t spelling out the whole chapter. This means they might be missing some of the typos that are less common but still lead to an increased risk of cancer. These tests also may only look at 2 to 3 genes, or chapters of the instruction manual, that are related to cancer, and the consumer does not have the option to personalize which genes the test looks at.

For example, the test may look at 2 genes related to breast cancer and 1 gene related to colon cancer, but this may not be helpful for someone with a family history of ovarian cancer. If you chose to do this type of testing, be sure to use a company that is FDA approved and CLIA certified to ensure the highest quality.

Medical grade genetic testing ordered by a genetic counselor is more comprehensive. These tests spell out full words or even sentences in the chapters of that instruction manual. They even look to see if parts of that chapter are missing or if there are extra pieces anywhere. Your genetic counselor can also customize the test to meet your needs. This means they can select to evaluate the genes related to your personal or family history of cancer to make sure you are getting more personalized testing.

The Results

Genetic counselors may also be of help in understanding the results that come back. When ordering direct-to-consumer testing, typically the results come through an email or online portal which can make it harder to get your questions answered right away. This may cause some anxiety for some people if they receive a result indicating that they have an increased risk of cancer and can’t get answers right away.

When testing is performed with a genetic counselor, the counselor will contact you with results and provide the necessary background information so that you can understand your results better. They will talk through the results with you and may be able to offer you recommendations about how your genetic test results should change your health screening and medical management.

The Cost

Outside of offering a test that provides more information, genetic counselors may be able to offer more benefits to their patients. Genetic testing ordered straight from the companies is typically a set, flat rate; a genetic counselor can run tests through insurance providers or inform patients about payment plans for testing, reducing the cost as much as possible for their patients. Genetic counselors may also be able to get free testing for your family members if they need genetic testing based on your results.

Finding a Genetic Counselor

If you or a family member are interested in genetic counseling and live in Tennessee, you are welcome to schedule an appointment through the Thompson Genetics Clinic (865-331-2350). The Genetics Counselors at Thompson Cancer Survival Center are board-certified and licensed. 

For those living outside of Tennessee, you may visit https://www.nsgc.org and click the yellow “Find a Genetic Counselor” tab to locate a genetic counselor local to them if they are located in another state.

Genetic testing is a personal decision and may not be right for everyone. If you have questions about the process, reach out to your local genetic counselor.

To learn more, you may want to read the blog post: Genetic Counseling versus Genetic Testing