However, observations from human cohorts intuitively show that HLA‐DRB1*15: 01's role in MS cannot be solely because of defective virus control, as this allele is only associated with MS and not with IM, CAEBV or other diseases that emerge from uncontrolled EBV replication,25 and antiviral drug for MS have been shown in clinical trials to be largely ineffective.64 This evidence concerns the gene HLA-DRB1 and myeloid sarcoma.