Polygenic score
Populations sometimes have different frequencies of genes. Before making a polygenic score, the data is changed so that genes that are different between populations will not affect the results. Scientists can use different ways of making polygenic scores more accurate. They choose to not use very correlated DNA variations that are close together, to avoid counting the same DNA variation twice. They can include only the DNA variations that they are sure of, or they can include even DNA variations that they are not sure of. They can use machine learning to do this better. They can also use DNA variations about traits related to the trait or disease that they are studying, in order to have more data.