KDM5B and cardiac arrhythmia: Among these were novel associations with the genes CTNNA3 and KDM5B. The CTNNA3 gene encodes the cytoskeletal protein catenin α3, which interacts with cardiomyocyte desmosomes and plays a role in cell adhesion.17 Variants in CTNNA3 have been putatively associated with arrhythmogenic right ventricle cardiomyopathy18 and rare variants in CTNNA3 have also been associated with familial AF.19 The KDM5B gene has not previously been associated with arrhythmias.