Repression of CELF function or over-expression of CELF proteins in heart muscle leads to cardiomyopathy in transgenic mice [2,3,4], and dysregulation of CELF-mediated alternative splicing has been implicated in human cardiac pathogenesis in myotonic dystrophy and diabetic cardiomyopathy [5,6,7]. Here, CEBPD is linked to myotonic dystrophy.