MBNL1 and myotonic dystrophy type 1: To obtain a comprehensive view of splicing regulation in mouse DM1 models we used RNAseq to examine quadriceps muscle from human skeletal actin long-repeat (HSALR) transgenic mice and Mbnl1−/−/Mbnl2+/− mice, designated here as Mbnl3⁄4KO mice.