Our data indicate that serum GDF15 is a highly selective diagnostic biomarker of CMT (AUC of 0.972, 95% CI; 0.936–1), while NCAM1 (AUC 0.748, 95% CI; 0.6268–0.869) is a more suitable serum biomarker of neuropathy progression. Here, GDF15 is linked to neuropathy.