More precisely, we presume that this difference in MS risk stems from either the GG (as a risk factor) or the GT (as a protective factor) genotype of CD33 rs3865444, as the GG one was more frequent, and the GT one was less frequent in MS patients compared to controls, while the observed frequency of the TT genotype did not differ between the two groups. This evidence concerns the gene CD33 and myeloid sarcoma.