ACE and familial dilated cardiomyopathy: The results of the study on the association between ACE rs4646994 polymorphism and the pathogenesis of DCM showed that allele gene model (D vs. I): OR = 1.39, 95% CI = 1.14–1.69, P=0.001; homozygote gene model (DD vs. II): OR = 2.02, 95% CI = 1.32–3.09, P=0.001; heterozygote gene model (ID vs. II): OR = 1.46, 95% CI = 1.01–2.12, P=0.045; dominance gene model (ID+DD vs. II): OR = 1.62, 95% CI = 1.14–2.29, P=0.006; recessive gene model (DD vs. ID and II): OR = 1.53, 95% CI = 1.12–2.08, P=0.007.