CGB7 encodes the beta subunit of human chorionic gonadotropin (hCG), a glycoprotein hormone essential for pregnancy maintenance 1. The CGB7 gene is one of four genes (CGB3, CGB5, CGB7, CGB8) encoding functional hCG beta subunits, with CGB7 differing by three amino acids from the identical CGB3/5/8 protein 1. CGB7 activates the ERK1/2 signaling pathway and appears functionally redundant with CGB3/5/8 isoforms, though with distinct kinetics of pathway activation 1. Uniquely among CGB genes, CGB7 expression is selectively induced by the tumor suppressor p53 through a direct transcriptional mechanism in trophoblastic and non-trophoblastic cells 2. In normal tissues, CGB7 is the predominant CGB gene expressed in breast tissue 3. CGB7 is dysregulated in multiple cancers, particularly urothelial bladder cancer where it is the most frequently expressed CGB gene 4. Notably, CGB7 expression associates with immunosuppression, decreased CD8+ T cell infiltration, and poor response to immune checkpoint inhibitor therapy 4. Environmental exposure to per- and polyfluoroalkyl substances (PFAS) significantly decreases CGB7 and hCG production in placental cells, suggesting potential reproductive toxicity 5.