This is a guest blog post written by genetic counselor Brianne Kirkpatrick, MS, LCGC, who specializes in DTC and ancestry counseling.

1. You know that ‘Terms and Conditions’ section that we all check off without reading? Think twice before doing that if your DNA is involved!
You may be giving rights to your DNA away in a direct-to-consumer (DTC) genetic test. The fine print you agree to in a Terms of Service agreement describes what may be done with your DNA, including policies on selling data, retaining biological DNA samples over time, and sharing information with law enforcement. The terms differ from one company to the next and you should review them before you buy.

2. Surprise! You may unearth information about your family that is unwelcome.
Every day we hear new stories of people discovering relatives they didn’t know they had after taking a home DNA test. Some consumers sign up to learn ethnicity “pie chart” results and opt in for the company’s ‘family member matching’ feature without realizing what lies ahead. DNA evidence can reveal that a relative was adopted (in or out of the family), conceived by a donor egg or sperm, or that the person sitting next to you at Thanksgiving is not your biological relative. Sometimes the news is welcome, and sometimes not so much. Support groups are popping up online for those bracing from the aftershocks of a surprise discovery after DNA testing.

3. No, DTC testing is not a substitute for medical testing.
The toolbox of genetic tests available for understanding medical risks is large, and it’s full of interesting tools. DTC test options are like a set of screwdrivers in the toolbox – they have their place and each is useful in certain situations. But you can’t rely on a set of screwdrivers if you want to build a fence, change a tire, or a nail a picture frame to the wall. If you want genetic testing for carrier testing before you have children DTC options exist but give limited results. For example, 23andMe testing covers about 40 conditions and uses only one technology. Companies in the clinical testing market, like Counsyl and Sema4, provide tests that screen for hundreds of recessive conditions, and their tests often involve multiple genetic testing technologies to give the most comprehensive results.

Understanding the difference between what you’re getting from a DTC test versus a medical-grade test can be tricky. This is where a professional, like a certified genetic counselor, can be critical. If you want carrier testing, have a personal or family history of a genetic condition or disease, or need to solve a medical issue, your best bet is to speak to a certified genetic counselor first. I’ve seen people comment that a DTC test is much less expensive than going to see a genetic counselor. However buyer beware. There are many tests – both direct-to-consumer and medical-grade. Be sure to get advice about which one is appropriate for you and is actually assessing the risks you think it is.

4. But yes, DTC testing can provide critical medical information.
Remember I wrote that DTC tests are like screwdrivers? Well, let’s not forget that screwdrivers can be really useful, easy to access, and also the right tool for the job! It is possible to get some valuable medical information from DTC tests. People have reported learning about medical conditions that they otherwise would not have known about had it not been for DTC testing.

5. Your DTC test may provide your raw genetic data file.
What in the world is raw data? It’s a huge computer file that contains the digital readout of the DNA results created from the spit you send in for DTC testing. Many DTC companies will allow you to download your raw data once you’ve had DTC testing. You will then need a computer tool to analyze it. Some analyzation tools are available for genealogy purposes only, some are for health, and some have a bit of an overlap (often unintentionally). None of them are regulated, or guaranteed to be “working” properly to give you reliable information, so users beware and be wise.

You need to know that the raw data from DTC testing is flawed. One abstract came out earlier in 2017 about the staggering false positive rate of findings that show up in raw data files. The algorithms behind the data are constantly changing and updating. So what the data tell you today may not be the same as what it tells you next year. This doesn’t mean that all of the data within the file are incorrect, but you should know they may be. If you plan to use these data for medical purposes, you should speak to a certified genetic counselor who specializes in this area. It is likely that a new DNA sample will need to be taken and the test repeated in a clinical laboratory. It is possible that your health insurance will cover these services and your genetic counselor can help make this happen.

6. Think before you gift.
Sometimes a gift you expect to be a smash hit turns into a big flop. A DNA test is not exempt, but the consequences may be more serious than buying those footy pajamas. I know because I’ve been responsible for a Great Holiday Gift Flop – giving DNA test kits to my unsuspecting parents who were confused, shocked, and not entirely tickled by my gift. From that experience, I learned that gifting a DNA test out of the blue is not guaranteed to be a good idea. Know your DTC test AND your gift recipient before you stick this box under the tree or menorah.


Brianne Kirkpatrick, MS, LCGC is a genetic counselor and DNA consultant through Watershed DNA, a private practice focused on direct-to-consumer testing that she started in 2016. You can find her on Twitter and Facebook, or visit her website at www.watershedDNA.com.