CTLA4 and myeloid sarcoma: Although Palacios et al. have found a reduction in the expression of CTLA-4 isoforms associated with certain alleles of the SNP −658 in MS patients and not in controls, which suggested the occurrence of epigenetic changes generated by the disease process, their overall suggestion was that the role of CTLA-4 in the pathogenesis of MS might be associated with the functional changes in its pathway rather than to genetic polymorphisms [151].