Genetic testing has expanded from clinical settings into the commercial sphere, offering insights into ancestry, health risks, and diagnoses. The rapid proliferation raises questions about the accuracy of these tests and their practical value (Wakefield et al., 2019). Determining whether a genetic test is valid and useful requires careful evaluation of its analytical performance, ability to predict clinical outcomes, and potential impact on an individual’s health and well-being (NIH, 2020).

Evaluating a genetic test involves assessing its validity and utility (NIH, 2020). Analytical validity addresses the technical performance of the test in the laboratory, including its accuracy and reliability in detecting the specific genetic target (NIH, 2020). In the United States, clinical laboratories generally adhere to CLIA standards to help ensure analytical validity (Katsanis & Katsanis, 2013). Clinical validity measures the test’s ability to consistently and accurately predict the presence, absence, or risk of a specific disease or health condition (NIH, 2020). This requires robust evidence linking genetic findings to the health outcome (Katsanis & Katsanis, 2013). Beyond validity, clinical utility assesses the practical usefulness of the test – whether using the result leads to tangible improvements in patient care or health outcomes, weighing benefits against potential harms (NIH, 2020). Achieving utility can require careful test selection and interpretation, emphasizing the value of expert guidance like genetic counseling (Resta, 2020; Solomon, 2024).

Applying these concepts helps analyze the diverse genetic tests available. Direct-to-consumer (DTC) Ancestry Testing analyzes SNPs to estimate biogeographical origins and connect users with relatives (Kirkpatrick & Rashkin, 2017). While SNP genotyping accuracy (analytical validity) is generally high, interpreting ancestry percentages depends heavily on proprietary databases, impacting interpretive validity. The tests possess very low clinical utility, serving primarily personal discovery goals. Results provide ancestry estimates and relative matching; genetic counseling can help users understand limitations and potential unexpected findings (Kirkpatrick & Rashkin, 2017). Another commercial category is DTC Health Risk and Wellness Testing, reporting on predispositions or carrier status, often based on GWAS findings (Wakefield et al., 2019). Analytical validity for tested SNPs is typically high, but clinical validity for complex disease prediction is often limited due to assessing a few variants with minor effects and the potential lack of generalizability across diverse ancestries. Clinical utility is frequently questionable, as results are not diagnostic and can cause anxiety or false reassurance without proper context (Wakefield et al., 2019). Results indicate statistical risk or carrier status, underscoring the need for consultation with healthcare professionals (NIH, 2020).

Clinical Diagnostic Genetic Testing aims to identify the genetic cause of individual symptoms, using methods from single-gene tests to whole exome sequencing (WES) (Katsanis & Katsanis, 2013). Analytical validity in regulated labs is high, and clinical validity can also be high if a clear pathogenic variant explains the symptoms. The clinical utility may be immense, potentially ending a diagnostic odyssey and informing management (Katsanis & Katsanis, 2013). However, interpreting vast data from WES remains challenging, often yielding Variants of Uncertain Significance (VUS) that require expert assessment (Resta, 2020). Clinical Predictive Testing is offered to asymptomatic individuals with a known family history of a condition like hereditary cancer (Katsanis & Katsanis, 2013). Clinical validity is strong for well-established tests, and clinical utility comes from enabling risk-reducing interventions (NIH, 2020). Clinical Carrier Screening identifies carriers for recessive or X-linked conditions to inform reproductive planning (Katsanis & Katsanis, 2013). Analytical validity is high for targeted variants, while clinical validity depends on panel relevance to ancestry. Clinical utility involves informing reproductive decisions (Katsanis & Katsanis, 2013). Counseling helps interpret results and options (Resta, 2020).

Genetic testing offers important benefits, including diagnosis, risk clarification, personalized treatment guidance, and reproductive information (NIH, 2020). However, there are some risks. Tests can be inaccurate or poorly predictive, and results, especially from DTC sources, may be misinterpreted without guidance, leading to psychological harm (Resta, 2020). Testing can reveal sensitive or unexpected information (Kirkpatrick & Rashkin, 2017). Privacy concerns and potential discrimination persist and the lack of diversity in genomic research limits test validity in many populations, potentially worsening health disparities (Wakefield et al., 2019). Interpretive challenges, like VUS, remain common (Katsanis & Katsanis, 2013). Genetic counseling is an indispensable resource for navigating these complexities, helping individuals make informed choices, understand results, manage uncertainty, and ensure testing aligns with their values (Solomon, 2024). Evaluating validity and utility, understanding limitations, and seeking expert guidance is crucial for the responsible use of genetic testing.

References

Katsanis, S. H., & Katsanis, N. (2013). Molecular genetic testing and the future of clinical genomics. Nature Reviews Genetics, 14(6), 415–426. https://doi.org/10.1038/nrg3493  

Kirkpatrick, B. E., & Rashkin, M. D. (2017). Ancestry testing and the practice of genetic counseling. Journal of Genetic Counseling, 26(1), 47–55. https://doi.org/10.1007/s10897-016-0014-2  

National Institutes of Health. (2020). How can consumers be sure a genetic test is valid and useful? MedlinePlus. Retrieved April 26, 2025, from https://medlineplus.gov/genetictesting.html

Resta, R. (2020). Birds of a feather? Genetic counseling, genetic testing, and humanism. Journal of Genetic Counseling, 29(6), 931–938.  10.1101/cshperspect.a036673

Solomon, I. (2024). Reduction of Health Care Costs and Improved Appropriateness of Incoming Test Orders- the Impact of Genetic Counselor Review in an Academic Genetic Testing Laboratory. Journal of the American College of Cardiology, 83(13S), 1102. https://doi.org/10.1007/s10897-018-0226-8

Wakefield, E., et al. (2019). The future of commercial genetic testing: Workshop recommendations on commercial genetic testing related reporting and counseling. Journal of Genetic Counseling, 28(1), 3–12. 10.1097/MOP.0000000000001260