MPZ and Charcot-Marie-Tooth disease type 1B: Indeed, a longitudinal analysis of the slowly progressive, late-onset demyelinating CMT1B mouse model, caused by a heterozygous deletion of the Mpz gene46,47, revealed an upregulation of Nrg1-I only during late disease stages (after P180), when demyelinating and remyelinating events become prominent (Supplementary Fig. 3f).