• Camille Krejdovsky

Precision Medicine: An Ethical Dilemma Informed by the Past

Precision medicine often brings to mind a futuristic view of health care, in which therapies can be tailored to patients’ needs based on their lifestyle, genetics, and environment. While this form of medicine seems like an innovation that will be implemented far in the future, the fundamental ideas behind precision medicine are already playing out in society. Due to the delay in widespread integration of genomic data in health care, the private sector has taken matters into their own hands, offering what has been termed direct-to-consumer (DTC) genetic testing. While the term “DTC genetic testing” might be foreign, the idea is not. One of the most prominent examples is 23andMe, a company that allows consumers to pay for insights into their health and ancestry. The basic idea behind the DTC model is simple: consumers spit into a tube, mail it back to the company, and receive information back about themselves, ranging from diet recommendations to risk for certain diseases. However, the implementation of the model has proved to be much less simple, raising a variety of ethical and technical concerns.

On a technical level, concerns arise about how the genetic data collected is being used. The most widely discussed is data privacy, especially with respect to holes in current genetic discrimination laws and in situations of changing company ownership. Since genetic information is identifying for both individuals and their family members, the decision of one person to share their genetic information could impact others negatively if used improperly. In addition, a second large technical concern lies in the accuracy of the tests. Most DTC genetic tests utilize single nucleotide polymorphism (SNP) genotyping in which variants in single base pairs in certain locations across the genome are characterized (1). Although whole genome/exome sequencing would generate more comprehensive results, it is also much more expensive (2). Because these SNP tests often attempt to communicate risk for multifactorial diseases based on information about a few variants, results returned are often incomprehensive and misleading to consumers (3). A study published in 2018 carried out clinical laboratory testing on 49 individuals who had previously taken a DTC test. The researchers reported an overall 40% false positivity rate in the results returned by the DTC companies as well as discrepancies between variants considered pathogenetic (4). While distributing misleading results is problematic in itself, the implications are even greater when the results are reporting on risk for diseases that will potentially impact a person’s lifespan and reproductive decision making.

Another large group of ethical concerns centers around participant understanding. While necessary, true informed consent is very difficult to obtain due to the online nature of the consent process and the complexities of secondary uses. Furthermore, incorrect interpretation of results by consumers could lead to distress, potentially inappropriate decision making, and strain on physicians who are not adequately trained in genetics (5,6). Genetic counseling could be key, but providing it is not current standard practice for these companies (6). In addition to providing genetic counseling, decisions need to be made about what individuals have the right to know about their genome. If the view is taken that individuals should have access to their genetic information, then the question shifts to what types of information should be accessible. Some maintain that in the realm of medical genetic testing, only results with direct clinical utility should be returned, whereas others argue for a sense of personal utility (2).

While these issues have been identified in the context of DTC genetic testing, they will all need to be addressed before genetic information can be widely used in the health care setting. While huge potential exists for precision medicine to save time and lives, we need to ensure that appropriate attention is paid to the ethics of venturing into this new era of clinical care. DTC companies have served as a sort of test run of the concept, providing us with valuable insight into both the concerns and potential of utilizing the clues hidden within the genome.

Review Editor: Rohan Gupta

Design Editor: Amber Smith


1. Raw Genotype Data Technical Details. 23andMe. Data-Technical- Details#:~:text=The%2023andMe%20genotyping%20platform%20detects,the%20DNA %20base%20or%20bases.&text=These%20DNA%20base%20differences%20are%20kn own%20as%20%22variants.%22.

2. Vayena E. Direct-to-consumer genomics on the scales of autonomy. J Med Ethics.2015;41(4):310-314. doi:10.1136/medethics-2014-102026.

3. Oh B. Direct-to-consumer genetic testing: advantages and pitfalls. Genomics Inform. 2019;17(3):e33. doi:10.5808/GI.2019.17.3.e33.

4. Tandy-Connor, S., Guiltinan, J., Krempely, K. et al. False-positive results released by direct-to-consumer genetic tests highlight the importance of clinical confirmation testing for appropriate patient care. Genet Med 20, 1515–1521 (2018).

5.Howard HC, Borry P. Is there a doctor in the house? : The presence of physicians in the direct-to-consumer genetic testing context. J Community Genet. 2012;3(2):105-112. doi:10.1007/s12687-011-0062-0.

6. Tamir S. Direct-to-consumer genetic testing: ethical-legal perspectives and practical considerations. Med Law Rev. 2010;18(2):213-238. doi:10.1093/medlaw/fwq01.

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