In particular, 17 genes (PDE3A, COL1A1, NR3C2, SLC6A4, MMP3, CALM3, NOS3, IL6, CRP, CDKN1A, KCNH2, SCN5A, ADRB1, CALM2, GJA1, DRD1, and CALM1) were co-associated with ZT, GLT, HET, and arrhythmia; 5 genes (CFTR, GALR2, APLN, DRD4, and CACNA1S) were co-associated with ZT, GLT, and arrhythmia; 3 genes (AGTR1, EDN1, and SULT2A1) were co-associated with ZT, HET, and arrhythmia; and, lastly, 1 gene (HRAS) was co-associated with GLT, HET, and arrhythmia. This evidence concerns the gene DRD4 and cardiac arrhythmia.