TBX21 and autoimmune thrombocytopenic purpura: Our previous study has shown that T-bet mRNA expression was statistical higher in patients with active ITP than that in normal controls (44), which was in accordance with our present results where T-bet mRNA expression was significantly higher in patients with active ITP than that in controls (0.02148 ± 0.01098% (n = 33) vs. 0.002748 ± 0.0005696 (n = 19), P < 0.0001) (Figure 2B).