Jacobs Journal of Anatomy and Physiology

The hCG Family of Independent Molecules

Published on: 2018-04-23


Human chorionic gonadotropin (hCG) is a very unique rule breaker to the basic guidelines of biochemistry and physiology, it is one name and a large group of 5 or 6 completely independent or separate molecules. Each has a common a-subunit and ß-subunit amino acid sequence and is separated by difference in O-glycosylation, differences in N-glycosylation, differences in sulfation and differences in mutations and merism (Table 1). It is with these differences that the forms of hCG somehow fold differently, bind different receptors and have partially-independent or completely independent roles. Recently, a simplified renaming was recommended, hCG-1, hCG-2, hCG-3, hCG-4, hCG-4ß and hCG-5. These names are used in parenthesis after the lengthy names commonly used and used in this report (Submitted 2016, “The hCG Family of Independent Molecules Needs Urgent Renaming.” Obstet Gynecol).