The direct-to-consumer genetic tests (DTC) tests allow anyone to receive a report on their ancestry, traits, or disease risk without a prescription. Companies like 23andMe popularized this model, selling saliva kits that promise to reveal your origins and predispositions. However, the tests they include polygenic scores (PGS) to predict complex diseases pose numerous challenges ethical, legal and scientific doubts.

In March 2025, 23andMe joined the Chapter 11 of the US bankruptcy law after years of declining demand and the 2023 personal data breach affecting nearly seven million customers【277920588596500†L40-L53】. This episode highlighted that storing millions of genomes in the hands of companies for commercial purposes carries risks. Many consumers are unaware of how their data is being used, and legislation has yet to update its protocols to protect them.

What are polygenic scores in consumer tests?

A polygenic score estimates a person's relative risk of developing a disease by combining thousands of genetic variants. In clinical practice, PGS are developed in controlled settings and interpreted with the help of professionals. But in the consumer market, companies market reports that reveal your "genetic risk" without proper clinical context. Companies often present risk relative to the general population, which can lead to misinterpretation.

A commentary from experts in Nature Genetics warns that many commercially available PGS are opaque: the algorithms and data they use are proprietary and not peer-reviewed【277920588596500†L40-L65】. They also point out that the accuracy of PGS decreases dramatically in non-European populations, because most of the data comes from people of European ancestry【368994030973972†L942-L949】. For example, the most advanced obesity PGS explains about 17 % of BMI variance in people of European ancestry, but only 2 % in an African cohort【368994030973972†L942-L949】.

Risks and problems identified

DTC tests with PGS have several limitations:

• Lack of transparencyCompanies often don't explain how they build their PGS or how accurate they are. They also don't clearly disclose their privacy policies or the commercial use of your data.
• Insufficient diversityBecause they are based on data from European populations, PGSs are biased and less reliable for people of African, Asian, or Latino origin. This can lead to discrimination or give a false sense of security to those who, based on their genetics, appear to be at low risk.
• Psychological impactReceiving a report indicating a high risk of cancer, diabetes, or obesity without professional guidance can cause anxiety, depression, or poor decision-making. A narrative analysis of PGS in the DTC setting highlights that many consumers misinterpret results and abandon healthy habits if they believe their risk is low. [999872599145720†L150-L163]
• Privacy and marketingSome companies sell genetic data to third parties, including insurance companies and pharmaceutical companies. The University of Edinburgh's Bioethics Committee is urging improved regulation to ensure companies inform and obtain explicit consent for any secondary uses of data. 【277920588596500†L149-L165】
• Limited indication for public health: Most PGS only capture a small fraction of the real risk. As we will see in the post 3, a study from University College London found that PGS detects, on average, only 11% of disease cases and generates numerous false positives【372282977355559†L26-L70】.

Recommendations for responsible use

The comment of Nature Genetics proposes several actions to improve consumer protection:

• Transparency and reviewCompanies should publish their methods and validations, submit them for peer review, and clearly explain their limitations. It is essential to know the percentage of variance explained and the population in which the score was validated.
• Informed consentUsers should receive clear consent materials that describe how their data will be stored and used, the risks involved, and what will happen if the company is acquired or changes its business model.
• Results in absolute terms: Instead of presenting relative risks (“you have a 50% higher risk of %”), they should offer absolute figures (“your risk goes from 2% to 3%”), intuitive graphs, and comparisons with modifiable factors such as diet and exercise.
• Professional support: Access to genetic counseling and health professionals is crucial to interpret results and guide decisions.

Some companies are beginning to implement these recommendations. However, the best way to integrate PGS into everyday life may be through precision nutrition professionals and platforms like Mefood Omics and OorenjiThese platforms combine genetics, microbiota, and habits to create personalized eating and lifestyle plans, always under the supervision of experts.

The value of education and regulation

To harness the potential of genomics without falling into quackery, education is needed. Understanding that PGS is not an oracle but a statistical tool This will allow us to make informed decisions. Governments and regulatory bodies should also establish clear standards on the scientific validity of tests, data protection, and risk communication. Some proposals include:

• Force companies to report detection and false positive rates of their PGS.
• Prohibit the marketing of high-risk tests without sufficient evidence and require approval from health authorities.
• Establish penalties for misuse of genetic data and guarantee the right to delete your information.
• Promote research in underrepresented populations to improve equity.

In Caloo We believe that innovation must go hand in hand with the protection of people. Therefore, in our services, we always request informed consent and explain the limitations of any biomarker used.

Conclusion: information yes, but with a head

Consumer genetic tests offer convenience and curiosity, but they should not replace professional consultation or science-backed prevention strategies. Polygenic scores can be useful in research and some clinical applications, but in today's commercial environment, their usefulness is limited and they can cause confusion or anxiety. Before purchasing a kit online, educate yourself, seek advice, and demand transparency. And remember that your lifestyle and environment remain the most determining factors in your health. For a holistic, evidence-based approach, visit our platforms. Mefood Omics and Oorenji, where we combine genetic data with everyday habits in an ethical and safe manner.

References

1. The future of polygenic risk scores in direct-to-consumer genomics – Nature Genetics Commentary
2. Polygenic Scores in the Direct-to-Consumer Setting – Narrative Review (BMJ Medicine)
3. Performance of polygenic risk scores in screening – BMJ Medicine
4. Genetic risk scores not useful in predicting disease – UCL News