Polygenic Risk Score

A polygenic risk score is a calculation that pulls together thousands of pieces of a person's genetic information to estimate the chances of developing a certain disease, or to gauge a physical trait like cholesterol levels.

Think of it like this: researchers build a prediction table by comparing the health records and genetics of huge numbers of people, then plug in your own genetic information to produce a score showing roughly how much risk you carry. The catch is that most of these prediction tables were built from studies of European-ancestry populations. Just as a health prediction table built from one neighborhood's data doesn't work well when applied to people from a different neighborhood, it's long been known that these scores lose much of their predictive power when applied to other population groups.

To close this gap, researchers have tried transferring what was learned from European-ancestry data to other population groups. But recent research has found that once a target population has accumulated enough of its own data, this transfer approach can actually make predictions worse rather than better.

In the article, a polygenic risk score is described as 'a statistical model that combines information from many genetic variants to predict the probability of developing a particular disease or trait.' It's worth remembering that this score isn't a diagnosis that definitively tells you whether you will or won't get a certain disease — it's simply a number that reflects a probabilistic tendency.