The interesting observation, supporting the role of HHV6 in MS pathogenesis, was finding a higher frequency of GG genotype in rs12722489 of IL2RA and T allele in rs1535045 of CD40 genes in patient having anti-HHV6 antibodies as well as a link between having anti-VZV antibodies in MS and CC genotype in rs1883832 of CD40 gene. Here, CD40 is linked to myeloid sarcoma.