A DTC genetic test is a genetic test that consumers can buy online or in stores and does not require a physician’s order. They are also known as direct-to-consumer genetic tests, at-home genetic testing, home DNA testing or direct-access genetic testing.
Consumers send the company a DNA sample, typically DNA derived from saliva, and after being analyzed, they can see the results in the provider’s website or in a written report.
In the analysis, hundreds of thousands positions in the genome are measured to provide individualized reports. Companies look at a set of sites in human genome that commonly differ between individuals, known as SNPs (single nucleotide polymorphisms).
Sets of evaluated positions differ between companies depending on their purposes. However, with the decreasing genomic sequencing costs, many companies are offering also full genome analysis.
How to choose the right DTC genetic test
Provider companies offer direct-to-consumer genetic tests for a variety of purposes. Most popular tests offer information about:
- genealogy or ancestry testing. They give information about the ethnicity and genetic connections between families, how much DNA a person has inherited from prehistoric humans, such as Neanderthals and Denisovans
- common traits and lifestyle factors, such as nutrition and fitness
- or to make predictions about health, including complex conditions as Alzheimer’s disease or Parkinson’s disease or information on carrier state for genetic conditions (e.g. Cystic fibrosis or hereditary hemochromatosis)
Normally, companies that provide these tests notify their clients that these reports are not meant to diagnose, prevent, or treat any disease or health condition. They are aimed for education, information or research purposes only.
As the number of companies providing at-home tests is growing along with the results they offer, customers have many doubts to choose a suitable one. For this reason, it is advisable that customers:
- consider their goals for testing
- assess the quality of the companies’ available services before pursuing any testing
- if the companies test for the SNPs, genes or conditions they are most interested in
- if they provide raw data or guidance regarding the results
Also, customers should think about whether there is any information they would rather not know and get informed how companies will protect their privacy and keep their genetic data safe.
If you have had your DNA tested, Genomapp can analyze your DNA raw data file to give you the maximum information.
National Human Genome Research Institute: Direct-to-Consumer Genomic Testing
Centers for Disease Control and Prevention (CDC) Genomics and Health Impact Blog: Direct to Consumer Genetic Testing: Think Before You Spit, 2017 Edition!
American College of Medical Genetics: Position statement on direct-to-consumer genetic testing (PDF)