The story

IGF-1 was first seen in 1957 as the sulfation factor, the substance growth hormone makes the liver release to build cartilage. In 1978 Ernst Rinderknecht and Rene Humbel in Zurich sequenced it and showed it looked like proinsulin. In Adelaide in the early 1990s, Geoffrey Francis, John Ballard and colleagues at CSIRO and GroPep built LR3: the Arg-3 swap and the front extension made it escape the binding proteins and act much more strongly. Frank Tomas in the same group showed it was strongly anabolic in rats under steroid stress. Russian endocrinologists, such as Gennadinik and Nelaeva, describe IGF-1 as the conductor of growth hormone's effects in metabolism, cell renewal and ageing.