Since CD49d proteins are responsible for CD34+ cells or blast attachment and homing to MSC30 an increased CD49d expression in MDS‐BMMSC and de novo AML‐BMMSC probably improves attachment, retention, self‐renewal, and homing of hematopoietic and leukaemia cells to the bone marrow niche, modulating chemotherapy response. This evidence concerns the gene ITGA4 and myelodysplastic syndrome.