Two protein families, CELF and MBNL, have been implicated in the mis-regulation of the alternative splicing of muscle and heart transcripts in DM1, including cTNNT2, IR, and ClC-1 (Philips et al., 1998; Ladd et al., 2001; Savkur et al., 2001; Charlet-B et al., 2002; Kanadia et al., 2003; Ho et al., 2004; Kino et al., 2009). Here, CEBPD is linked to myotonic dystrophy type 1.