A study on a large African-American group revealed that having DRB1*15 not DQB1*0602 allele strongly increased in patients with MS, whereas carrying the DQB1*0602 allele with other DRB1 alleles (i.e., not DRB1*15 alleles) was present at identical frequencies in patients and controls.23 An association research revealed that DRB1*1501, rather than DQB1*0602, constituted the principal MS disease risk gene.23 Here, HLA-DRB1 is linked to myeloid sarcoma.