Nearly 2.5% and 1.4% of the variance in AD diagnosis and criterion count, respectively, were explained by polygenic liability to SRE-T in the SAGE-EA data. Predictions were less significant in other target cohorts, potentially due to the similar ascertainment for alcohol dependence of SAGE and COGA. For example, even though Yale-Penn-AA was ascertained for alcohol dependence, it has a high rate of other illicit drug dependence which may have impacted predictions. Polygenic liability to SRE-5 was poorly related to AD phenotypes, consistent with its lower genetic correlation with AD diagnosis and criterion count.
