GCH1 and familial dilated cardiomyopathy: We found that the expression of NOS1 (3.781 fold, P < 0.05), DYNLL1 (2.854 fold, P < 0.05) and SPR (3.018 fold, P < 0.05) were higher in DCM group than in CNT, and GCH1 mRNA levels were decreased (−1.320 fold, P < 0.05).