Interestingly, only 4 of 9 patients (44%) who were seropositive for isolated MOG-IgA and had a diagnosis of MS11 presented CSF-specific OCBs, clearly less than in those with MOG-IgA/-IgG seronegative MS (4/9 [44%] vs 325/351 [93%], respectively; P < .001) (Figure 2B and eTable 3 in Supplement 1). The gene discussed is MOG; the disease is myeloid sarcoma.