We observed a significant increase in the frequency of all three Treg populations in CLL patients than HVs, namely Tregs Tbet+ (0.7%, range 0.2–2.8% vs 0.1%, range 0.03–1.1%, respectively), Tregs GATA-3+ (0.1%, range 0.01–2.4% vs 0%, range 0–0.1%, respectively), Tregs RORγt+ (0.7%, range 0.1–3.9% vs 0.03%, range 0–0.2%, respectively) (Fig. 1d). The gene discussed is TBX21; the disease is B-cell chronic lymphocytic leukemia.