HLA-DRB1 and myeloid sarcoma: Multiple sclerosis (MS) is a chronic immune-mediated disorder of the central nervous system, influenced by a combination of genetic and environmental factors, including Epstein-Barr virus infection, smoking, adolescent body mass index, sun exposure, and vitamin D. Among the genetic factors, the HLA-DRB1*15:01 allele stands out as the most significant and has been shown to interact with various environmental and lifestyle factors in MS [1–3].