HLA-DRB1 and myeloid sarcoma: Using the top 12 validated disease variants for MS including HLA-DRB1 (Additional file 1), we estimated the collective genetic risk in the discovery dataset, yielding a classification sensitivity of 35.1% and a specificity of 93.5% (Table 2), suggesting the presence of many additional susceptibility alleles in the strata of data that failed to achieve genome-wide significance.