To study the in vivo role of TET1 in thyroid cancer, we generated thyroid-specific Tet1 knockout mouse model by crossing LSL-BrafV600E, LSL-Tet1 and thyroid peroxidase (Tpo)-Cre mice to generate thyroid cancer with various genotypes (Supplementary Fig. 2A). The gene discussed is TET1; the disease is thyroid cancer.