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Polygenic risk score

From ISOGG Wiki

A polygenic risk score (PRS) is a score that gives you a genetic risk for something, as calculated using many SNPs at the same time. The score is typically calculated as a score for a disease, but it can be used for any trait that is affected by many different SNPs. There are many ways to calculate and report such scores and it as an area under rapid development, but it always include the summarization of effects from many different SNPs in an individual.[1]. In traits and diseases that are genetically complex, polygenic risk scores are more useful in risk prediction than looking at individual mutations. [2] Most common diseases like heart disease, diabetes, autoimmune disease and mental disorders are genetically complex.

From the point of view of genetic genealogy, polygenic risk scores are mostly of interest if you want to predict ancestral traits like height or hair colour, and perhaps follow them through generations. Like most common diseases, these traits are genetically complex, meaning that it is simply not possible to look at one SNP at a time. Two examples of online genetic height calculators are given in the resources section below.

Further reading



  1. Nature Genetics 2018. GPS for navigating healthcare
  2. Khera et al 2018 Genome-wide polygenic scores for common diseases identify individuals with risk equivalent to monogenic mutations

See also