Constructing a timeline of genetic engineering is a tricky task – where do you start? The list of discoveries, ideas, thoughts and innovations that contributed to the field can go on for miles. And of course many would trace its origins way back in time to when humans first manipulated genomes for the domestication of crops and animals. However, I’ve picked five moments that I consider pivotal in genetic engineering history, starting with the world’s first recombinant DNA organism.
Herb Boyer and Stanley Cohen use recombinant DNA technology to create the world’s first recombinant DNA organism. Attracted by the potential advantages of genetic engineering they removed plasmid DNA from a bacterial cell and inserted foreign genetic material into it. When daughter bacterial cells were produced they expressed the protein products of the foreign DNA.
The pair transferred genes offering antibiotic resistance into a plasmid which was inserted into E.coli. Subsequent generations were resistant to these antibiotics. They also introduced genes from the toad Xenopus laevis, and these were shown to be functioning in later generations.
Boyer and Cohen first met at a scientific conference and discovered that their work dovetailed into each other’s. Boyer had noticed some unique properties of restriction enzymes of E.coli bacterium. Namely, that they cut DNA strands in a particular way, leaving cohesive ends which could be attached to other DNA strands in a precise way. Cohen had been working on a way of isolating plasmids and removing them from bacterial cells. Together their knowledge paved the way for the field we know as genetic engineering.
Rudolf Jaenisch creates the world’s first transgenic animals. He introduced foreign DNA into mice embryos and the resulting animals had the modified gene in their tissues. This profound moment gave scientists a new way of studying genes and development.
Genentech, the first genetic engineering company was founded by Herb Boyer (see above) and venture capitalist Robert Swanson. Swanson had heard about Boyer’s and Cohen’s pioneering recombinant DNA work and requested a meeting with Boyer. Bowled over by the money man’s enthusiasm for the technology the meeting concluded with the formation of the company. Its aims, according to the company’s website – "to develop a new generation of therapeutics from genetically engineered copies of naturally occurring molecules important in human health and disease.” A year later and the company produced the first human protein (somatostatin) in a microbe (E.coli). Genentech is still going strong today.
Genentech announced the production of genetically engineered human insulin. Researchers had created synthetic genes with the code for insulin production and inserted them into a strain of E.coli. The genes were ‘switched on’ inside the bacterium and its own genetic machinery began to translate the foreign genetic material to produce insulin.
After approval from the Food and Drug Administration, the first genetically engineered drug hits the market, human insulin produced by recombinant bacteria and developed by Genentech.
And the rest as they say …