Furthermore, we employed bisulfite clone method to validate methylation pattern of γ-globin promoter in β0/β0-thalassemia patients and normal controls, and observed that hypomethylation at − 50, + 17, and + 50 CpG sites of γ-globin promoter in the TFH patients compared with the TFL patients and normal controls (Fig. 2c). Here, ZC3H12D is linked to thalassemia.