Interestingly, this study also identified an independent DMR in the MHC region in CD4+ T cells as being associated with MS, specifically, a large hypermethylated DMR in RNF39. The biological relevance of this locus can only be speculated at this stage; however, it resides within the gene body and spans an intron/exon boundary, so it is plausible that hypermethylation is involved in aberrant expression of alternately spliced transcripts or a regulatory element for nearby genes. The gene discussed is CD4; the disease is myeloid sarcoma.