This gene is a member of the pregnancy-specific glycoprotein (PSG) gene family. The PSG genes are a subgroup of the carcinoembryonic antigen (CEA) family of immunoglobulin-like genes, and are found in a gene cluster at 19q13.1-q13.2 telomeric to another cluster of CEA-related genes. The PSG genes are expressed by placental trophoblasts and released into the maternal circulation during pregnancy, and are thought to be essential for maintenance of normal pregnancy. The reference genome contains a nonsense mutation that disrupts the coding sequence, suggesting that this gene may be evolving into a pseudogene. Alternative splicing results in multiple transcript variants.