For the above reasons, the purposes of this cohort study are to examine distribution of TBXAS1 gene polymorphism in this population, investigate the associations between TBXAS1 gene polymorphism and MS, and explore whether gene polymorphism could act as biomarkers in MS and its components, or plays a role in MS-related damage, then ultimately optimizing the preventive and treatment strategies. The gene discussed is TBXAS1; the disease is myeloid sarcoma.