MBNL1 and dilated cardiomyopathy: In addition, upregulation of Kcna4 and downregulation of Ckmt2, genes linked to dilated cardiomyopathy and arrhythmia, have been observed in cardiac-specific MBNL1 and MBNL2 double-knockout mice (23) and were also misregulated in CUG960 +dox mice (Figure 6G, Supplemental Figure 13, I and J, and Supplemental Figure 14C).