ATF7IP and atrial fibrillation: In summary, based on the fact that AZA intervention reversed CACNA1C gene expression in HepG2 and T47D cell lines, combined with clinical samples and multi-omics statistical analysis, we identified that DNA methylation at three CpG sites in intron 30 of the CACNA1C gene is associated with AF status, and potentially regulated by ATF7IP and KAT2B.