By Dr. David S. KimResearchers have known that the pancreas secretes several peptide hormones critical to metabolic regulation, most notably insulin and glucagon, since the early 1900s. With the advent of recombinant peptide synthesis in the 1970s, scientists not only began working on isolating the gene responsible for insulin production but fabricating it outside the body. In 1978, scientists at Genentech turned bacteria into factories able to transform sugar into insulin by cutting the insulin...