 Chordin was originally identified in the African clawed frog ("Xenopus laevis") in the laboratory of Edward M. De Robertis as a key developmental protein that dorsalizes early vertebrate embryonic tissues.It was first hypothesized that chordin plays a role in the dorsal homeobox genes in Spemann's organizer.The chordin gene was discovered through its activation following use of gsc (goosecoid) and Xnot mRNA injections.