Although the etiology of MS remains elusive, genes within the human leukocyte antigenic (HLA) loci, such as HLA-A*02:01, HLA-DRB1*15:01, HLA-DRB5, HLA-C, and TNF, have been firmly associated with MS susceptibility (12). The gene discussed is HLA-DRB1; the disease is myeloid sarcoma.