PLAC1 (placenta-specific 1) an X-linked gene whose expression is limited primarily to the placenta [, ]. It is essential for normal placental and embryonic development []. PLAC1 is also expressed by a wide variety of human cancers [, ].
This family consists of placenta-specific protein 1 (PLAC1), oocyte-secreted protein 1/2/3/4 (Oosp1/2/3/4). PLAC1 may play a role in placental development [, ], while Oosp1 may regulate oogenesis and certain liver functions [, ].
