HLA-DRB1 and myeloid sarcoma: Most previous genetic and immunological studies suggested DRB1*15:01 as the disease-predisposing gene in MS (5, 6) are in agreement with the GWASs, suggesting that greatest risk to MS is driven by the HLA-DRB1*15:01 allele, while association to MS of other alleles of DR15 haplotype is only secondary to their LD with HLA-DRB1*15:01 allele (4, 7).