Given that fact and considering that differences in pathophysiology may well translate into different treatment requirements, as already shown in AQP4-IgG-positive NMO [47] and suggested for MOG-IgG-positive EM [34, 35], studies aiming at enhancing our understanding of the immunopathophysiology of pattern II and III lesions seem highly warranted. The gene discussed is AQP4; the disease is neuromyelitis optica.