Description
HCG is produced by the trophoblastic cells of the placenta and stimulates the ovaries to synthesize the steroids that are essential for the maintenance of pregnancy. HCG is one of the four human glycoprotein hormones: chorionic gonadotropin (CG), luteinizing hormone (LH), follicle stimulating hormone (FSH), and thyroid stimulating hormone (TSH). They are dimers consisting of alpha and beta subunits that are associated noncovalently. The alpha subunits of these hormones are identical (CGA), however, their beta chains are unique and confer biological specificity. The beta chain for HCG is the beta 3 subunit of chorionic gonadotropin (CGB3)