Most common conditions are not caused by a single gene. A polygenic risk score (PRS) combines the small effects of hundreds or thousands of genetic variants into a single number that estimates your genetic predisposition for a condition.
How a PRS is built
Researchers run genome-wide association studies to find variants linked to a trait, weight each variant by its effect size, and sum those weighted contributions across your genome. The result places you on a distribution relative to a reference population.
What a PRS can and cannot tell you
- Can: flag higher-than-average genetic predisposition, which may inform screening or lifestyle conversations.
- Cannot: predict with certainty that you will or will not develop a condition. Genetics is one factor among many.
Important limitations
Many scores were trained largely on European-ancestry data and transfer imperfectly to other populations. A PRS is a probability, not a diagnosis, and should be read alongside biomarkers, family history and lifestyle.
Putting scores in context
genyHealth.ai computes polygenic risk scores and, crucially, sets them next to your labs, wearables and the latest research, then reinterprets them over time as the science evolves. Request access.
This article is for general education and is not medical advice.