The downregulation of Ezh2 and upregulation of Ccnd1 in the teratoma-forming cells in Dnd1ter/ter testes in comparison to wild-type germ cells (Figs 2 and 5), and the upregulation of Ccnd1 and its decreased H3K27me3 due to Ezh2 KD in ES cells (Fig. 4) suggested that the downregulation of Ezh2 due to Dnd1 deficiency leads to the conversion of germ cells into teratoma-forming cells via the upregulation of Ccnd1 expression in Dnd1ter/ter testes. Here, DND1 is linked to teratoma.