Consistently, further investigation of specific markers for EC2 and F1 showed that the expression levels of ACKR1, CCL19, CCL21, CXCL9, SELP, IL33, and MADCAM1 were significantly increased in thyroid tissues of HT patients (Supplementary Fig. 4C, Supplementary Data 4). The gene discussed is MADCAM1; the disease is hematocrit.