Human chorionic gonadotropin

In molecular biology, human chorionic gonadotropin (hCG) is a hormone produced by the embryo following implantation. The presence of hCG is detected in pregnancy tests. Some cancerous tumors produce this hormone; therefore, elevated levels measured when the patient is not pregnant can lead to a cancer diagnosis. However, it is not known whether this production is a contributing cause or an effect of tumorigenesis. The pituitary analog of hCG, known as luteinizing hormone (LH), is produced in the pituitary gland of males and females of all ages.As of December 6, 2011, the United States FDA has prohibited the sale of "homeopathic" and over-the-counter hCG diet products and declared them fraudulent and illegal.

Structure

Human chorionic gonadotropin is a glycoprotein composed of 237 amino acids with a molecular mass of 25.7 kDa.

It is heterodimeric, with an α (alpha) subunit identical to that of luteinizing hormone (LH), follicle-stimulating hormone (FSH), thyroid-stimulating hormone (TSH), and β (beta) subunit that is unique to hCG.