HLA-DRB1 and myeloid sarcoma: The HLA DRB1*15 allele was more common among the MS patients with OGBs in the cerebrospinal fluid than those without OGBs in the cerebrospinal fluid (80.6% vs. 64.2%; OR = 2.3, 95% CI 1.017-5.301; P = 0.043) (See Additional file 3: Figure S1 for the original data of association of HLA DRB1*15 allele with oligoclonal bands).