The Fish That Glow
Last December, I visited the New Picture House with some friends to watch the long-awaited Hunger Games prequel, The Ballad of Songbirds and Snakes. Besides the allure of re-entering a dystopian world, I had long forgotten, I was fascinated by the iridescent snakes, which the villain Dr Gaul dubs her “rainbow of destruction". These creatures are genetically modified animals or — as known in the Hunger Games universe — “mutts". Like the previous films and books, these animals were aimed at harming humans via venomous bites. But how realistic are these creatures and are they as impossible as they seem?
Humans have been modifying animal genomes since the domestication of livestock through artificial selection. By choosing the individual with a desired trait, such as a friendlier dog and allowing them to breed, we can alter the traits we see in animals. This is how we achieved modern-day dogs from wolves, as well as so many other animals we see on farms and in our homes.
In more recent years, the direct altering of an organism’s genome has become possible. Today, genetic engineering is done using a recent biotechnological tool called CRISPR (Clustered Regularly Interspaced Short Palindr). CRISPR is an enzyme, originally found in bacteria, used to cut specific DNA sequences. The enzyme allows for the insertion of another ‘transgene’ (the transfer of a gene from one organism to another) into the genome in a process called transgenesis.
This method of genetic engineering is likely how the bizarre animals we see in the Hunger Games series were formed. In the real world, such technologies have been used in a variety of circumstances. In humans, the technology is being considered to help treat sickle cell anaemia and other genetic diseases, whilst in animals it is used to engineer crops with pest resistance, and even zebrafish who glow.
2003 saw the appearance of genetically altered animal companions to suit human aesthetic and physiological needs. One of the first was the controversial GloFish. GloFish first came on the market in the United States in 2003, following the discovery of Green Fluorescent proteins (GFPs) in crystal jellyfish. Scientists learned that if they could insert the gene that encodes the fluorescent protein into the genome of other organisms, the new organism would produce the same protein and glow.
The genetic modification of animals isn’t new: though, recently there has been discussion in the engineering of hypoallergenic cats by removing the protein Fel d 1, a major cat allergen.
Image: Wikimedia Commons
Likewise, micro-pigs, animals created by the Beijing Genomics Institute, initially used as models for human diseases and tested through genetic engineering techniques, were supposed to be sold back in 2015, with custom colours and sizes available. However, the plans were shut down due to ethical and ecological concerns from the public.
But the engineering of animals doesn’t stop at companions. We also see the likes of farm animals being genetically modified to express resistance to diseases, increase their nutritional content and decrease the number of pollutants in manure. Likewise, wild animals are being modified to limit zoonotic disease transmission (diseases passed from animals to humans) and reintroduce extinct species like the much-missed woolly mammoth.
There has been a significant amount of controversy over all genetically modified organisms (GMOs), in particular the use of genetically modified animals for aesthetic purposes. It is unknown how GMOs will interact with other organisms. For example, GloFish have been detected within southeastern Brazilian streams, concerning scientists as they are not native to Brazil and hence act as an invasive species.
Often, the investigation into new modifications requires the sacrifice of some animals, although such investigations are usually done for medical and pharmaceutical purposes such as antibody harvesting in rabbits. Animals being genetically modified continues to be a controversial topic, with some regulatory frameworks set up by global organisations. Due to the advancing nature and expansion of GMO use, these regulations may change in the coming years.