Colocalization

A "credible set" is the set of variant(s) at a locus that is most statistically likely to contain the causal variant by finemapping methods.

What colocalization does is to ask if association signals overlap not just at one SNP but for the whole credible set that was finemapped. If the credible set of an eQTL for a gene overlaps well the credible set of a genetic association, that can be one clue to the underlying gene which could be associated with the trait that you are studying.

Click here to read more about how colocalization is done in FinnGen and click here to read more about the file format of the FInnGen colocalization results.