First, we showed that the IS metaGRS had stronger association with IS than previously published genetic scores, doubling the effect size of the most recent genetic score. To put its performance in context, we estimated the IS metaGRS identified the 1 in 400 individuals who were at threefold increased risk of IS, a level of risk and frequency similar to common monogenic cardiovascular diseases, such as familial hypercholesterolaemia (FH), a risk factor for myocardial infarction35. Monogenic forms of stroke, such as CADASIL, are relatively rare36, thus the IS metaGRS may represent a potential new avenue to more common polygenic risk stratification, in combination with established risk factors.
