PMP22 and Charcot-Marie-Tooth disease: ELISA quantification showed a 22.2% increase in expression of NCAM1 in CMT patients compared to controls (P = 0.0004), with 36.1% increase in CMT1A patients (P = 0.0028) and 11.6% increase in patients with mutations in GARS/AARS (P = 0.0318) (Fig. 3A).