We successfully assessed the generalizability of European identified genetic associations for ECG traits in African Americans derived from an electronic medical record. Additionally, we report novel associations for ECG traits in African Americans. Replication of these findings in an independent African American population is needed to confirm these associations. Indeed, in the future, replication may be possible within the eMERGE network given that the network has expanded with respect to study sites and sample size. Most of the associations identified in European and Asian -descent populations failed to generalize due to power (as a consequence of sample size and low minor allele frequencies). However, there were several adequately powered associations that did not generalize to African Americans. These data suggest that the functional variant has yet to be identified for these traits by GWAS and highlight the need for future fine mapping studies in a large African-descent population.
