B. Western blot analysis for Mbp and P0 on lysates from Pmp22-/- and WT mice P20 shows decreased myelin protein expression levels at both time points in Pmp22-/- nerves, results are mean ± SEM, p=0.0500 with the exception of the P0 protein level at P20, for which the difference between Pmp22-/- and WT nerves is not statistically significant, p=0.1000, one-tailed Mann Whitney U test, representative of two independent experiments. 