For myelodysplastic syndrome (MDS)-MRD positive samples, red cells accounted for 3.36% of nuclear cells in the H gate, expressing CD34, bright CD117, dim CD33, dim HLA-DR, and dim CD200, but not expressing CD4, CD7, CD56, CD13, CD64, CD71, CD38, and CD96, which were malignant myeloid primitive cells (Figure 2b). This evidence concerns the gene CD7 and myelodysplastic syndrome.