Direct to Consumer Genetic Testing

What is DTC Testing?

Direct to consumer genetic tests are a type of genetic test that people can buy directly from private companies without seeing a healthcare professional.

They include tests that;

  • Provide information about your ancestry. This is done by looking at markers in your genetic code that give clues about roughly where your family originated.
  • Provide information about health risks. These tests predict the chance of developing certain conditions such as heart disease, dementia and breast cancer

Due to the increase in prevalence of DTC testing, the All Wales Medical Genomics Service (AWMGS) is seeing a marked increase in service demand from those seeking subsequent diagnostic clarity

What is the difference between NHS genetic testing and DTC genetic testing?

NHS Genetic Test DTC Genetic Test
Directed at making a diagnosis
Directed at giving information about health risks, but not for making a diagnosis
Genetic testing is directed at your specific condition or health problems as assessed by a healthcare professional. Your medical history, family history and lifestyle factors are a key part of choosing the right test for you.
DTC genetic tests are not specific to you and so don’t take account of your medical history, family history or other lifestyle factors.
Pre-test and post-test genetic counselling is routinely available to help you understand your genetic test and any result.
Genetic counselling is usually not available to help you understand your genetic test or any result.
Genetic testing is targeted to look in detail at the part of your genetic code that’s relevant to your specific condition or health problems. Any genetic result is carefully interpreted, taking into account your personal medical history.
Most DTC tests do not look at the genetic code in detail. These tests looks for certain differences in the genetic code called Single Nucleotide Polymorphism, or SNPs. Some research has shown that certain combinations of SNPs are associated with a higher chance of developing some health conditions.
Genetic testing takes place in an NHS accredited laboratory
Genetic testing does not take place in an NHS accredited laboratory

What is the AWMGS position on DTC genetic testing?

We fully support individual efforts to be more health aware and to adopt a healthier lifestyle. In some respects, DTC genetic tests have increased awareness of Genetics and its influence on health.

When it comes to DTC genetic tests, it is important that you know exactly what the test you are buying involves. Some DTC tests look at SNPs or genetic alterations associated with an increased risk of certain cancers. These results could have significant implications for your or other members of your family. However, there have been several cases where these results have been wrong. Your DTC test result could cause a lot of undue worry in these circumstances. Similarly, having a ‘normal’ result, does not mean you are not at increased risk of certain cancers. This is because these tests aren’t specifically looking at the relevant parts of the genetic code for this information.

If you are concerned about your family history of disease (including cancer), or feel you might have a Genetic condition, please discuss this with your GP who can refer you to your local Clinical Genetics service if appropriate.

If you choose to have a DTC genetic test, you should make sure that you understand what the company will do with your data. Some companies might store, sell or conduct research on your genetic data. You should also be aware that the All Wales Medical Genomic Service cannot interpret any raw data or results obtained from a DTC genetic test.

More information can be found on the Genetic Alliance website and the Association of Genetic Nurses and Counsellors website.

See also talk and article from the British Medical Journal.