HLA-DRB1 and myeloid sarcoma: Reactome pathways enriched for DNAm had cross-study overlap - 45% of pathways enriched in Ausimmune DNAm modules were also enriched in EIMS (4.82-fold, p < 0.001).<h4>Interpretation</h4>EBV, lower vitamin D, low sun exposure, and HLA-DRB1*1501 risk variant act in concert and through common epigenetic pathways to impact MS onset risk.