Some studies noted that patients with a CIDP-like phenotype despite anti-MAG antibody positivity were less likely to exhibit classical features of anti-MAG neuropathy − such as myelin lamellae widening on biopsy, high antibody titers, or positive immunofluorescence − suggesting potential biological heterogeneity [35,36]. The gene discussed is MAG; the disease is chronic inflammatory demyelinating polyradiculoneuropathy.