This result was highly surprising, since it provided formal evidence in this particular case for an autoimmune encephalomyelitis and the final diagnosis was not MS but MOG antibody associated inflammatory demyelinating disease (MOGAD), which differs from MS by its clinical presentation and its response to therapy (Reindl et al. 2013; Jurynczyk et al. 2017). The gene discussed is MOG; the disease is myeloid sarcoma.