MTAP and dilated cardiomyopathy: Assessment of single-nucleus RNA-seq from human hearts 65—including non-failing (NF), hypertrophic cardiomyopathy (HCM), and dilated cardiomyopathy (DCM) samples—suggests that compared to other 9p21.3 genes, MTAP showed the highest expression levels across all cardiac cell types (Figure S 7B).