Consistent with the manifestation of neuroaxonal dystrophy, immunohistochemical analysis of NeuN (neuronal nuclear antigen), NF200 (large myelinated axons marker) and CNPase (oligodendrocyte marker) revealed a dramatic reduction in neuronal cell bodies, extensive decrease and fragmentation of neurofilaments and a decrease in oligodendrocytes in the medulla of all 5-month-old Tecpr2 ki/ki mice (Fig. 2a, Supplementary Fig. 2c). This evidence concerns the gene CNP and neuroaxonal dystrophy.