MBNL1 is also a known regulator of alternative splicing of a number of transcripts whose splicing is mis-regulated in DM1, including insulin receptor (IR), muscle-specific chloride channel (CLCN1) and sarcoplasmic/endoplasmic reticulum Ca+2 ATPase (ATP2A1, also known as SERCA1) [32]-[36]. This evidence concerns the gene INSR and myotonic dystrophy type 1.