TTN and dilated cardiomyopathy: TTN is a well-established dilated cardiomyopathy gene,24 and its association with AF has been hypothesized to be partly driven by an atrial cardiomyopathy.15 Interestingly, we also identified an AF association with pLOF variants in the PKP2 gene, which plays a major role in arrhythmogenic right ventricle cardiomyopathy.25 Common variants in a locus near PKP2 have previously been associated with AF in GWASs, and our study corroborates these findings with evidence of a role of pLOF variants in PKP2 in AF.