Of these, 27 studies [4, 5, 6, 11, 12, 13, 14, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36] were included in the meta-analysis to show an association betweenACE I/D gene polymorphism and DCM (Fig. 1a); 7 studies [11, 15, 19, 20, 26, 28, 30] correlated AGT M235T gene polymorphism and DCM (Fig. 1b). Here, AGT is linked to familial dilated cardiomyopathy.