Peripheral neuropathy and chronic inflammatory demyelinating polyneuropathy (CIDP) have been reported in patients with multiple sclerosis (MS) [1, 2], and common antigens between the central nervous system (CNS) and peripheral nervous system (PNS), such as myelin basic protein (MBP) and myelin-associated glycoprotein (MAG), were suspected to be pathogens of the coexisting MS and CIDP [3]. Here, MAG is linked to multiple sclerosis.