The percentages of IL-22+CD4+ T cells were positively correlated with Th17 cells (r = 0.8815, p<0.0001) and IL-17A+IL-22+CD4+ T cells (r = 0.8914, p<0.0001), but were negatively correlated with Th1 cells (r = −0.6110, p<0.0092) in the HT patients. The gene discussed is IL22; the disease is hematocrit.