Despite the strong relation with MS, TDLs can also occur as isolated, monophasic events or in other demyelinating diseases such as myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), neuromyelitis optica spectrum disorder (NMOSD), and acute disseminated encephalomyelitis (ADEM), though this is considered rare. The gene discussed is ART4; the disease is myeloid sarcoma.