The higher methylation levels in VMP1/MIR21correlated strongly with lower expression of mature miR-21 in CD4+ T cells, whereasno correlation was observed with VMP1. The negative correlationwith miR-21 levels was the strongest at the CpGs in the MIR21 gene.Methylation at the same CpGs has previously been shown to negatively correlate withmiR-21 expression in naïve CD4+ T cells upon activation.16 Accordingly, we observed lower expression of mature miR-21 in RR-MS patientscompared to SP-MS and controls, and this difference became significant in a largerindependent cohort. The gene discussed is VMP1; the disease is myeloid sarcoma.