GSK3B and muscle atrophy: Note that the GSK3β signal in a patient DM1-1 without muscle phenotype based on the clinical information and the grip and ankle strength tests at the time of the blood sample collection is very weak and barely seen on the film; however, other DM1 patients in this group have muscle phenotypes including myotonia (DM1-2 and DM1-3), muscle atrophy (DM1-2, DM1-3 and DM1-4) and muscle weakness (patients DM1-2, DM1-3, DM1-4 and DM1-5).