Considering the complex structure of the HLA locus, with LD extending over large distances, and our findings of DRB1*15:01-specific hypomethylation in monocytes, we investigated whether the identified methylation-mediated SNPs confer risk of MS independently of the DRB1*15:01 haplotype (Fig. 1). Here, HLA-DRB1 is linked to myeloid sarcoma.