Patients with HLA DRB1*08 allele had lower IgG index compared to patients without this allele (0.58 +/− 0.17 and 0.73 +/− 0.31, respectively, p = 0.04), and HLA DRB1*15 allele was more often found among MS patients with oligoclonal bands (OCBs) in cerebrospinal fluid than among those without OCBs (OR 2.3, CI 95% 1.017-5.301; p = 0.043). The gene discussed is HLA-DRB1; the disease is myeloid sarcoma.