As well, Son et al. were able to detect the aquaporin-4 (AQP4) antibody expressed in Neuromyelitis optica, a rare disease of the central nervous system that affects the optic nerves and the spinal cord, without pretreatment and using a CNT-based FET functionalized with (AQP4) extracellular loop peptides [315]. This evidence concerns the gene AQP4 and neuromyelitis optica.