HLA-DRB1 and myeloid sarcoma: Most of the haplotypes showed no association with ethnicity, sex, EDSS, and MS course except for the HLA-DRB5*01+-DRB1*1501+-DQB1*0602- haplotype that was positively associated with EDSS steps 5 to 10 (p=0.014) and non-RRMS (p=0.023).