This week in Science History: 6-09-10

By Peter Dearden 06/09/2010 2

This week in Science History
Megan Leask, PhD student, Laboratory for Evolution and Development

Production of human insulin by bacteria: 6 September, 1978

In 1978 on the 6th of September U.S. scientists announced the production of human insulin by a strain of E. coli bacteria, that had been genetically engineered after months of creative use of gene-splicing techniques.

A normal body’s production of insulin takes place within cells of the pancreas. In patients with type I diabetes, however, this production does not occur and thus they require insulin injections in order to control their blood glucose levels. Purified animal-sourced insulin was the only type of insulin available to diabetics until this amazing feat in genetics research occurred and, in 1982, insulin was the first recombinant DNA drug to be marketed, Humulin by Eli Lilly & Co.

John Snow removes the handle of the Broad Street water pump: 8 September, 1854

It is 1854, Soho, London, 500 people have died from a large cholera outbreak, and the hero of the story is an anesthetist by the name Dr John Snow. On September 8th he removed the handle of the Broad Street water pump in London, effectively halting any further spread of cholera. He identified drinking water as the vessel for transmission of the disease after he discovered that cholera cases occurred in the homes which obtained their water from the Broad Street Pump. The move is considered one of the most symbolic gestures in the history of public health at a time when it was thought that diseases such as cholera, chlamydia or the Black Death were caused by a miasma (ancient Greek: “pollution”), a noxious form of “bad air”.

Scientifically John Snow contributed to the formation of the germ theory but it wasn’t until 1890 when Robert Koch devised a series of proofs that the germ theory of disease became widely accepted. The “John Snow” pub now stands beside the pink granite slab marking the site of the original pump.

Alec Jeffreys envisions DNA fingerprinting: 10 September, 1984

On the 10th of September 1984, geneticist Alec Jeffreys had a ’eureka moment’ in his lab in Leicester, England. Within half an hour after looking at an X-ray film image of a DNA experiment, which unexpectedly showed both similarities and differences between the DNA of different members of his technician’s family, he realized the possible scope of DNA fingerprinting.

DNA fingerprinting is a technique that uses variations in the genetic code to identify individuals. DNA fingerprinting was first used as a police forensic test to identify the rapist and killer of two teenagers, Lynda Mann and Dawn Ashworth, who were both murdered in Narborough, Leicester in the 1980s. Colin Pitchfork was identified and convicted of the murders after samples taken from him matched semen samples taken from the two dead girls. This turned out to be a godsend  for Richard Buckland, the main suspect, who could have been convicted and sent to jail for life for murders he did not commit.

DNA fingerprinting has since been superseded by the advent of Polymerase Chain Reaction, which allows the amplification of specific areas of genetic code. Regions of DNA called microsattelites or short tandem repeats vary amongst the population and by testing ten microsattelites plus a marker for sex the discrimination power of DNA fingerprinting is one in over a billion.

2 Responses to “This week in Science History: 6-09-10”

  • From Graham Wallis

    This brings back memories! We worked at Leicester 1983-86. The irony about Colin Pitchfork is that he was caught because he AVOIDED the police DNA screen of males in the area. He actually paid someone (100 quid?) to stand in for him. Unfortunately for Mr Pitchfork, he chose someone rather dull, who later bragged about his easy money in the pub (our local at the time, in the village of Fleckney). He was overheard by an alert customer, who reported him to the police, and Colin was arrested. During the arrest at his home, his wife apparently had to be restrained from attacking him with a carving knife.