Direct to consumer (DTC) or DIY genetic tests are available for anyone to purchase, and their use is increasing. How accurate and useful are these DTC genetic tests and where can you find more information on these tests?
What are DTC genetic tests?
Direct to consumer (DTC) or DIY genetic tests are available for purchase over the internet by anyone. They usually involve a saliva or cheek swap sample, which is sent to a laboratory. The DNA is extracted, analysed and the results are sent directly to the consumer, instead of their doctor.
What are these tests looking for?
These tests read our DNA. Your DNA is inherited from your patents and includes information for growth and development. We each have variations in our DNA which may or may not contribute to our personal characteristics, including risk of disease. DTC genetic tests read the order, or the sequence of your DNA, and compare your variations to others stored on their database. Some tests claim they can use this information to assess your likelihood of developing a disease, however many of these variations have few evidenced-based links to disease.
How accurate or useful are DTC genetic tests?
Research shows that these DTC tests might not be that accurate. In one study from the University of Exeter, these tests gave inaccurate results over 80% of the time.
It’s important to know that genetics (and our DNA) have some influence on our health; environment and lifestyle factors also play an important role on our risk of developing a disease. Therefore, while these tests might provide some interesting information, they should be used with caution.
Things to consider when getting genetic testing
Given that genetic testing can provide such important information about you and your family members (remember, you share your DNA with your relatives), it’s important to arrange testing through your doctor or a genetic counsellor.
They can ensure that:
- You receive enough information to understand testing and the results
- You understand the risks and benefits of testing
- Your test is performed by an accredited pathology laboratory and will give accurate results
- Testing is appropriate for your situation
- You are aware of what testing may or may not show you about your health
- You have access to genetic counselling support if required
Want more information?
If you have concerns, or are interested in learning more about genetic testing, the first step is to talk to your doctor.
Your doctor will be able to give you advice on the most appropriate tests for you. If genetic testing is suggested by your doctor, you will be referred to a clinical setting in Australia. You will be provided with genetic counselling and doctors will interpret the results of your testing.
Murdoch Children’s Research Institute was recently part of a study that looked at Australian’s thoughts and experiences with personal genetic testing – the Genioz study. They used their findings to develop some great community resources, including making sense of online DNA testing and the possible implications of completing these DTC genetic tests.
Paper citation: Weedon Mn, Jackson L, Harrison JW, Ruth KS, Tyrrell J, Hattersley AT and Wright CF. Use of SNP chips to detect rare pathogenic variants: retrospective, population based diagnostic evaluation. BMJ. 2021; 372:n214. doi: 10.1136/bmj.n214.