HLA-DRB1 and myeloid sarcoma: The apparent female specificity of the EBV reactivation as an event triggering relapses can be explained by the fact that anti-EBNA1 antibody titers and HLA-DRB1*15∶01 have been shown to interact as risk factors in MS [29]–[31] and that HLA-DRB1*15∶01 has been suggested to confer risk just in female subjects [32].