Gonadotropin-releasing hormone and gonadotropin-releasing hormone receptors. The decapeptide GnRH is derived from posttranslation processing of a tripartite 92–amino acid (AA) pre-pro-GnRH. The first 23 AA is a signal peptide and the last 56 AA is known as GnRH–associated protein (GAP). GnRH is encoded from a single gene located on the short arm of chromosome 8.