We conducted parallel GWAS in nine samples of European ancestry and combined the results via meta-analysis. We applied two phenotypic strategies aimed at capturing common (pleiotropic) genetic effects shared across the five core ADs: GAD, PD, social phobia, agoraphobia, and specific phobias. We conducted two types of analyses in each sample based upon complementary approaches to modeling the comorbidity and common genetic risk across the ADs: (1) case-control (CC) comparisons, in which cases were designated as having “any AD” versus supernormal controls, and (2) quantitative factor scores (FS) estimated for every subject in the sample using confirmatory factor analysis.
