The colocalisation analysis in Open Target Genetics is performed using the coloc method (Giambartolomei et al., 2014).
Coloc is a Bayesian method which, for two traits, integrates evidence over all variants
at a locus to evaluate the following hypotheses:
- H0: No association with either trait
- H1: Association with trait 1, not with trait 2
- H2: Association with trait 2, not with trait 1
- H3: Association with trait 1 and trait 2, two independent SNPs
- H4: Association with trait 1 and trait 2, one shared SNP
This analysis tests whether two independent associations at the same locus are consistent
with having a shared causal variant. Colocalisation of two independent associations from two GWAS studies may suggest a shared causal mechanism.