To test this hypothesis, we made use of a rat model (LEWzizi) that originally descended from the zitter (zi/zi) rat, a spontaneous attractin (Atrn) mutant [22, 42] presenting with a variety of neuropathological features that resemble key aspects of MS pathology, such as neurodegeneration [52, 53], hypomyelination [18], microgliosis [16, 49], extensive iron accumulation [49] and dysregulated anti-oxidative systems [11]. The gene discussed is ATRN; the disease is myeloid sarcoma.