Humans have been engineering life for thousands of years. Say two of your wheat plants were especially bountiful, or a chicken was exceptionally large, you did the logical thing and bred the best together, to create a greater number of the higher-quality product. We never quite understood how this worked, until the molecule which codes life was discovered.
The Function of DNA
DNA or deoxyribonucleic acid is what controls the outward appearance of an organism, and all the inward workings, from protein synthesis to reproduction. Information is encoded in the structure of the molecule – four nucleotides, A T C and G, are paired together. This makes a code which carries instructions. Change the instructions, and the being carrying those instructions changes, too. When this was discovered by scientists, it changed the face of biology, forever.
As soon as DNA was discovered in the 1960s, scientists tinkered with it. They bombarded plants with blasts of radiation in order to cause random mutations in the DNA. The goal was to obtain a useful mutation by pure chance. This, unsurprisingly, resulted in a lot of dead plants, but sometimes it actually worked. In the 1970s, scientists inserted snippets of DNA into bacteria, plant and animal cells. This is what has revolutionised medicine – using this form of genetic engineering, we have made bacteria which produce insulin, a hormone we previously had to harvest from the liver of dead animals. This has saved many human lives, as well as animal ones.
The first genetically modified food, or GM crop, to be sold as the ‘Flavr Savr’ tomato in 1994. This tomato contained an extra gene which suppressed the build-up of a rotting enzyme, prolonging its life. In our current age, genetic engineering has given so-called ‘golden rice’ to developing countries which provides many vitamins that people would otherwise lack, and other genetically modified crops that may be resistant to certain pests or herbicides.
Most recently, CRISPR has revolutionised the field of genetic engineering and has the potential to put an end to the diseases which grip today’s society. A more unusual and wonderful use of genetic engineering today is ‘spider goats’; goats, who were given a gene from a spider which produces silk proteins. The goats produce the protein, and it is able to be harvested from the goat’s milk, enabling us to mass produce spider’s silk – an extremely strong material that is stronger than steel. On the lighter side, glow in the dark fish were engineered by inserting a jellyfish gene into fish embryos, making them bioluminescent. Such fish can be bought in pet shops for as little as eight pounds.
This all sounds fantastic – crops that will feed the world, bacteria which save lives and even glow in the dark fish. But the truth is, there is a double standard when it comes to genetic modification. The general public of today accepts using genetic engineering in medicine, like using modified bacteria to produce insulin, but some are against using genetically modified foods to feed the population, otherwise known as GM crops.
So, why are so many opposed to genetic engineering in the lab, when humans have been selectively breeding for thousands of years? I will be exploring this prospect in my next article.