In total, we analyzed 71 T-ALL cases: 19 AYA (15–39 years of age) and 52 children (<15 years of age), five control samples (normal T-cells of healthy bone marrow donors <18 years of age) and six samples of normal thymocytes (CD34+ and CD4+CD8+). The gene discussed is CD4; the disease is acute lymphoblastic leukemia.