KL and familial dilated cardiomyopathy: Quantitative RT-PCR analysis of Klotho mRNA expression in the heart and the kidney as a positive control revealed a significantly upregulation of full-length Klotho in DCM hearts as compared to non-failing control hearts (3.50 ± 0.51 vs. 1.53 ± 0.18; p = 0.002, Fig. 3C).