Assessing the utility of electronic medical records (EMRs) systems coupled to DNA repositories as a tool for genome science is one of the primary objectives for the National Human Genome Research Institute’s electronic MEdical Records and GEnomics (eMERGE) Network (McCarty et al. 2011). Studies from eMERGE, including those on PR interval, have demonstrated that EMR-based genetic studies replicate existing findings and discover new ones (Crosslin et al. 2011; Denny et al. 2010; Denny et al. 2011; Turner et al. 2011). Here we performed a GWAS of ECG measurements to identify novel genetic associations and describe the extent to which previous associations generalize in African Americans within the eMERGE network. We also examine reasons for non-generalization of associations in our African American study population.
