My mother has always said, “You get what you pay for.” It’s a motto that has stuck with me for over four decades and one I find applies to everything from yogurt to clothing to genetic testing. Yes, genetic testing.
The cost of genetic testing continues to go down significantly. This, paired with the general population’s curiosity about themselves, their health, and the impact of their genes on both has allowed many to buy direct-to-consumer genetic tests (DTC-GT). But whether you are investing hundreds or thousands in a DTC-GT, heck, even if it’s a $99 holiday special, there are things you might want to know about them before shelling out some change. The information below highlights differences between these tests and diagnostic genetic testing (DGT), a.k.a. clinical genetic testing, which are considered the gold standard of genomics in medicine.
Access
DTC-GTs can be ordered by anyone without having to request the test from a doctor or genetic counselor. In today’s busy world, one or more less appointments can make a big difference, especially given the often-lengthy wait time for in-person genetic visits.
DGT, on the other hand, must be ordered by a healthcare provider, preferably one that can discuss the benefits, limitations, and potential impact of the results. This is often not a person’s primary care provider but rather a genetic counselor or specialist.
Privacy
Each DTC-GT company has their own privacy policies and will state what is and isn’t protected, including whether your data may be shared with third parties or used for research purposes. Be sure to check the company's data protection measures to ensure your genetic information is secure.
All DGT information is protected by the Health Insurance Portability and Accountability Act (HIPAA), which is a law that ensures the confidentiality and security of your healthcare-related information.
Purpose and Use
DTC-GT are generally used for personal interest or recreation. They are termed “Genertainment” by genetic professionals. They provide information about ancestry, traits (e.g., lactose intolerance, dimples, and muscle composition), health risks (e.g., predisposition to certain diseases like diabetes or mental health conditions), and pharmacogenomics. These tests can’t diagnosis a condition, nor should the results of this testing be used to make medical decisions.
DGT are used to diagnose or rule out a specific genetic disease in someone who has symptoms or a family history of a certain condition. They are used to guide medical decision-making and treatment plans. There are currently over >8000 clinical genetics tests available, which is why talking with a genetic counselor is advisable to ensure the most appropriate one is ordered for you.
REAL LIFE EXAMPLE:
Maven’s mother, maternal aunt, and maternal cousin were all diagnosed with breast cancer in their forties. Maven is currently 25 and is concerned about her own risk for breast cancer. She is considering pursuing the 23andMe test which includes Genetic Health Risks. She mentions this to her OBGYN who recommends talking with a genetic counselor. The genetic counselor obtains a thorough personal and family history, finding out not only the types of breast cancer in Maven’s family and how the diagnoses were made but that Maven’s maternal grandfather had prostate cancer at the age of 58 and his brother had pancreatic cancer at the age of 60. She then discusses that 23andMe tests for only 44 out of >4,000 variants in the BRCA1 and BRCA2 genes and instead recommends that one of Maven’s affected relatives pursue DGT first. If a genetic variant is identified, then DGT for that specific genetic variant in Maven and her other relatives would be recommended.
OUTCOME:
Maven’s mother, then subsequently her maternal aunt, three maternal cousins, and self were identified to carry a genetic variant in the BRCA1 gene that was NOT one of the 44 tested for through 23andMe.
TAKE HOME MESSAGE:
Had Maven pursued genetic testing through 23andMe because of her concern for breast cancer, her results would have been negative when in fact that test simply did not test for her specific family variant. Had Maven not talked with a genetic counselor and pursued the appropriate genetic test, she would have missed potentially lifesaving screening measures.
Regulation and Accuracy
DTC-GT has less regulation compared to diagnostic tests. While some companies voluntarily follow industry standards, the level of oversight varies. And while they can provide reasonably accurate results, they may not be as precise or comprehensive as diagnostic tests.
DGT is highly regulated by several health authorities, including the FDA, to increase accuracy, reliability, and clinical relevance. As they use stringent laboratory techniques and interpretation by trained medical professionals and methods, including genetic counselors, variant curators, and bioinformatics, results tend to be much more reliable and accurate.
REAL LIFE EXAMPLE:
Eva and Pedro are thinking of having kids. They tell Eva’s OBGYN that they both pursued DTC-GT and were not found to be carriers of the same recessive genetic condition. The OBGYN asks if they want to talk with a reproductive genetic counselor as Eva reports that her paternal aunt has intellectual disabilities. The genetic counselor discusses Eva’s family history and the risk to a future pregnancy. She also reviews that 23andMe looks at a limited number of genetic variants in a limited number of genes and offers the couple more comprehensive carrier screening.
OUTCOME:
Eva pursues expanded carrier screening and is found to be a carrier of Smith-Lemli-Opitz (SLO). Pedro then pursues carrier screening for this condition and is also found to be a carrier. At their follow-up genetic counseling appointment, their reproductive genetic counselor discusses the chance for Eva and Pedro to have a child affected with SLO (25%) and all their preimplantation and prenatal genetic testing options. Eva and Pedro pursue preimplantation genetic testing for SLO and transferred an embryo that was not identified to carry both Eva’s and Pedro’s SLO variant.
TAKE HOME MESSAGE:
Had the couple not talked with a genetic counselor and pursued the appropriate genetic test, they would not have known they were at an increased risk to have a child with SLO.
Interpretation and Follow-up
Results from DTC-GT are provided directly to the consumer, often with explanations from the testing company. Actually understanding them may require additional research or consultation with a healthcare provider. Medical follow-up is typically not included and thus falls on the shoulders of the consumer.
Results from DGT are interpreted by healthcare providers, including genetic counselors, who explain the implications of the results and appropriate medical management, including changes to screening, treatment, and lifestyles.
A Note About Raw Data
Some direct-to-consumer genetic testing companies make raw data available to download. Raw data are the particular A’s, C’s, T’s, and G’s of the DNA extracted from the sample provided. It is challenging to interpret raw genotype data on your own. Most DTC-GT companies caution that the raw data are only for research or education and are not suitable for medical purposes, such as diagnosing a disease. To “help” with this, several online “third-party interpretation” services offer analysis and interpretation of the raw data collected by another company.
To Sum It Up
Don’t get me wrong, I’m not against DTC-GT testing. Anything that promotes awareness of genetic diseases and health is a win in my book. In addition, DTC-GT results stay out of your medical records and under the radar of your insurance provider. While there are protections against genetic discrimination, they are not limitless and let’s be real, insurance companies are rarely about patient care. That said, while DTC-GT is not coverage by insurance, they may be eligible for reimbursement through flexible or health spending accounts if the testing included health information. In addition, confirmatory clinical testing or management may be covered. Finally, your anonymous data can be added to a large database that can be used to further medical research and the field of genetics.
Yet they come with potential disadvantages, including the chance that you will get unexpected information about your health, family relationships, or ancestry, and that any positive results should be discussed with a healthcare provider and confirmed with DGT, which may bring you back around to the spot you were trying to avoid in the first place.
THE ULTIMATE TAKE HOME MESSAGE:
DTC-GT companies often tell their customers that their results are for information, education, and research purposes only—they are not meant to diagnose, prevent, or treat any disease or health condition.
DTC-GT can provide an introduction into your genetic health. But it’s only part of the story and may not be the most meaningful part of yours as other genetic and environmental factors, lifestyle choices, and family medical history can throw in plot twists that affect the likelihood of developing many disorders. Because of this, these factors, along with the benefits, risks, and limitations of DTC-GT, are best discussed with a genetic counselor to ensure you pursue the most appropriate test to address your concerns.
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