As shown in Fig. 4G, in the bone marrow transplantation of WT to Cd34-CreERT2;Rosa26-tdTomato mice, a large amount of fibroblast markers co-stained with tdTomato, proved that non-bone marrow CD34+ cells are the main source to replenish fibroblast pool in cardiac hypertrophy (Fig. 4G; Additional file 1: Figure S5E). The gene discussed is CD34; the disease is cardiac hypertrophy.