Understanding Polygenic Risk Scores
Polygenic risk scores (PRS) are numerical indicators derived from multiple genetic markers associated with specific diseases or traits. Unlike monogenic testing, which focuses on single gene mutations, PRS evaluates the cumulative effect of many genetic variants. This approach has shown potential in predicting risks for common conditions such as coronary artery disease, type 2 diabetes, and certain cancers.
Ethical, Legal, and Social Implications
Despite the promise of PRS, their integration into clinical practice raises several ethical, legal, and social issues (ELSI). These concerns are not entirely new, as they echo those encountered with monogenic testing, but they manifest differently in the polygenic context.
- Relevance to Family Members: Genetic information is inherently familial. The correlation of PRS among family members necessitates guidelines for sharing risk information responsibly.
- Secondary and Incidental Findings: The potential for incidental findings in PRS testing calls for ethical guidelines, particularly regarding genome-derived ancestry information.
- Role of Expert Mediators: The complexity of PRS data requires skilled mediators, such as genetic counselors, to help patients interpret and act on their results.
- Potential Harms: Concerns about psychosocial impacts, false reassurance, and overdiagnosis must be addressed through careful reporting strategies and patient education.
Addressing Health Disparities
A significant challenge with PRS is their variable predictive power across different ancestry groups, which can exacerbate health disparities. Most PRS data are derived from individuals of European ancestry, limiting their applicability to other populations. Efforts to gather diverse genetic data are crucial to improving PRS accuracy and equity.
Clinical and Public Health Integration
The dual application of PRS in clinical and public health settings introduces unique ethical considerations. Clinicians must balance individual patient autonomy with public health goals, such as reducing health disparities and maximizing population benefits. This requires a nuanced understanding of the endpoints being targeted and the ethical frameworks guiding these efforts.
Practical Implications for Practitioners
Practitioners can enhance their skills by engaging with the evolving science of PRS and its ethical dimensions. This involves staying informed about the latest research, participating in interdisciplinary discussions, and advocating for policies that address the ethical challenges of PRS use. Additionally, practitioners should consider the following actions:
- Participate in training sessions on PRS interpretation and ethical considerations.
- Collaborate with genetic counselors and other experts to support patients effectively.
- Advocate for diverse genetic research to improve PRS applicability across populations.
- Engage in discussions about the ethical use of PRS in both clinical and public health contexts.
To read the original research paper, please follow this link: Polygenic risk scores in the clinic: new perspectives needed on familiar ethical issues.
