The HLA-DRB1*15:01 allele has been identified as a major genetic risk factor for MS as well as in other diseases such as Myasthenia Gravis in European populations [28]; individuals who carry this allele have been shown to have a significantly increased risk of developing pediatric-onset MS (POMS) and adult-onset MS (AOMS) [29]. This evidence concerns the gene HLA-DRB1 and myeloid sarcoma.