Although CRIPTO expressed from the TDGF1 gene is predominant in ESCs and germ cell tumors, a highly homologous pseudogene, TDGF1P3, is expressed and likely produces functional protein (CRIPTO-3; CR-3; TDGF3) in various cancer types, including colon, breast and lung [105,106]. Here, CRIPTO3 is linked to germ cell tumor.