Furthermore, we found that there were no significant differences in the expression levels of Tet1 between the third generation (P3) and tenth generation (P10) after virus infection (Additional file 1: Fig. S1A–C), indicating that lentivirus-mediated shRNA can maintain the low expression of Tet1 in iHepSCs for a long time. The gene discussed is TET1; the disease is viral infectious disease.