The Transmembrane protein with an EGF-like and two follistatin-like domains 2 (TMEFF2) gene is located on chromosome 2q32-q33 and encodes a 374-residue long single polypeptide, type-I transmembrane proteoglycan. According to the HUGO gene nomenclature committee, the aliases of TMEFF2 include, HPP1, Tomoregulin (TR), Transmembrane protein TENB2 (TENB2), Cancer/testis antigen family 120, member 2 (CT120.2) and Transmembrane protein containing EGF and follistatin domains (TPEF). TMEFF2 was identified and characterized by at least five independent groups within the time span of approximately a year.