Sep 22, 2017 Choh Hao Li, a Chinese-born biochemist was responsible for the identification and purification of the growth hormone . He is also associated with the synthesis of the hormone. It was in 1981 that recombinant HGH was used for the first time in human therapy. Before recombinant DNA technology was used to produce human growth hormone, the hormone from the pituitary glands in cadavers was extracted for the purpose of deficiency treatments. There were several failed attempts at creating an entirely synthetic HGH. In the late 1950s, John C. Beck and his colleagues conducted a study on the effects of the growth hormone from the Rhesus macaque, an old world monkey . The subject was a 13 year old male with hypopituitarism, a condition in which there is decreased hormone secretion by the pituitary gland. It was found that both the human and monkey growth hormone had a significant impact on the enhancement of nitrogen storage. The subject was able to retain calcium, sodium, potassium, and phosphorus. It was also found that there was a significant amount of weight gain in the subject. A problem arose in 1985, when individuals who received HGH derived from cadavers 10-15 years earlier started to develop unusual cases of Creutzfeldt-Jakob disease . It was believed that infectious agents causing the disease were passed on along with the HGH derived from cadaver. As a result of this incident, the market for cadaver-derived HGH was immediately stopped. The same year, biosynthetic human growth hormone was finally developed and took over the role of pituitary-derived HGH. By 2005, you could find recombinant growth hormones such as Jintropin, Ansomone, Riptropin, Hygetropin, Nutropin, Genotropin, Saizen, Norditropin, and Humatrope.