A recent study by Matsa et al. (108) reported the identification of three functional endothelial NO synthase gene (NOS3) polymorphisms, T786C in the 5’-untranslated region, 27 bp VNTR in intron 4, and G894T in exon 7 in patients with DCM. Here, NOS3 is linked to familial dilated cardiomyopathy.