To set the clock back, on 11 January 1922 Banting and Best first injected animal insulin made from pancreatic extract into a diabetic patient in Toronto, Canada. The first injections were not successful however on 23 January 1922 a new series of injections on the boy patient resulted in a drop of the patients’ blood glucose levels to near normal. This medical scientific breakthrough marked the end of the sentence of death for diabetic patients who before 1922 were forced to eat sparingly as their bodies had lost the ability to metabolise food properly and at best their life expectancy was one to two years following diagnosis.

By the end of 1923 animal produced insulin was being used safely to treat diabetic patients in the Western world and purified versions of animal insulin were developed in forthcoming years.

In 1925 six year old Patricia Cheeseman was the first person to be treated successfully with insulin in the UK at Guy’s Hospital, London.

understanding of DNA by Watson and Crick in the 1950’s led to the development of genetic engineering techniques which led to the biosynthesis of what is now called genetically engineered or ‘Human Insulin.’