L1TD1 (ECAT11) is a member of the family of Embryonic Stem Cell Associated Transcripts (ECAT) that play an important role in stem cell biology. ECAT4 (Nanog) is a master regulator for the maintenance of mESC and hESC. ECAT5 was identified to be Embryonic stem cell expressed Ras (ERas), a Ras-like oncogene that is important in regulating mESC proliferation. ECAT9 (GDF3) is an important factor that helps maintain mESC pluripotency by inhibiting bone morphogenetic protein (BMP) signaling. L1TD1 is highly enriched in undifferentiated hESC and L1TD1 is a target gene of Nanog.