Of the ten transcripts that we identify here as being spliced differently in urine exRNA of DM1 patients, five of them, Mbnl1, Mbnl2, Mapt, Nfix, and Vps39, previously were reported as sensitive indicators of therapeutic ASO drug effects in skeletal muscle of HSALR mice4,6. Here, MBNL1 is linked to myotonic dystrophy type 1.