Fig. 5. Disease severity according to the domains of GNE mutations. A: The onset age did not differ significantly among the three subgroups of KD, ED/KD, and ED. B–D: Disease progression as represented by the number functional joint sets according to disease duration significantly rapid in the order of KD (B), ED/KD (C), and ED (D) (p=0.0062). ED: epimerase domain, KD: kinase domain.