Gene-editing has been a major scientific advancement, but the limits of such endeavours must be known as there are inherent dangers in doing so
Biotechnology can be taken as a biology for industry. It can also be defined as manipulation of genes or their components of microorganism via genetic engineering for production of new commercial products such as antibiotics, hormones, etc. We are fast entering into an unnatural world.
Though many of us believe that nature is worth preserving, that even aside from its utility, there is an intrinsic value to having a world of biodiversity. But conserving nature is ill served by going into the back gear of an unnatural world. For example, without the hybrid seeds of drought resistant crops, and without chemical fertilizer and pesticides, it is not possible to feed the galloping rise in population. Since no new technology is available that can replace the hybrid seeds and chemical fertilizers, we would need about a fourfold increase of land required for agriculture.
Human population is steadily increasing in geometrical progression and the pressure on natural landscapes and sanctuary is increasing. Biotechnologically engineered crops achieve great efficiency and productivity that enable us to reduce our agricultural footprint, which is hard to imagine by presently available means. Similarly, without genetic engineering, gene therapy would not have been possible. With the gene therapy scientists were able to change the DNA of the patient, which was not gene editing but delivering into the patient cell some engineered DNA to counter the faulty gene that caused the disease.
Gene therapy was not always a sure shot. A young man died in the US due to a massive immune response caused by a virus transporting gene that triggered cancer causing gene which led to leukemia in five patients. But incremental improvements in genetic engineering laid the foundation for more ambitious gene editing. Genetic editing in essence fixes the ways to edit the flawed sequence of DNA in relevant cells of the sufferer. This paved the way for gene editing.
The invention of gene editing requires two steps. First, researchers had to find the right enzyme that could cut a double strand break in DNA. Then a guide was needed to precisely target the cells’ DNA where they wanted to make the cut.
This enzyme is called nucleases. In 2000, the scientists found a tool, known as Fokl Enzyme which is found in the soil and pond bacteria. It has two domains one that serves as scissors that can cut DNA and another that serves as a guide telling it where to go. These domains can be separated, the first can be programmed to go anywhere.
Then came the CRISPER, it had a cutting enzyme which has Cas9 and a guide that led the enzyme that can be guided to spot on a DNA strand. The CRISPER guide was not a protein but a snippet of RNA.
But accelerating genetic engineering is risky. Tinkering with the ecosystem can go awry. Biodiversity serves as a template for ecosystems. It is something like that in a flying plane, if a bolt drops, the plane will fly and even if two bolts drop the plane can still fly. But if several bolts give way, the plane will dash. Likewise, the ecosystem is balanced because there is a natural balance between predator and prey, a complete holistic food chain.
To simplify, from microbes deep in the soil to the uppermost canopy of tree tops, all life works together and creates a rough equilibrium continually racked by boom and bust. At least, that is the theory of the ecosystem. As human use became so much more intense, pockets of conservation have been seen spread across the globe. The story of ‘Can toad’ in Australia provides an example.
Sugarcane crops in Australia were being attacked by beetles. In other parts of the world, ‘Cane toads’ attack beetles. Hence, ‘Cane toads’ were introduced in Australia to protect sugarcane crops. The plan failed and toads multiplied and their population is estimated to be 200 million covering a wide range. They started eating native insects, frogs, bird’s eggs, instead of beetles. Being poisonous, the toads killed many potential predators that might have been controlled. Rather than being a benefit, the toads became a major pet. It is still not understood how to control their populations.
But CRISPR-Cas9 described above has potential which can be applied to cells that can be targeted to spread a mutation leading to only maleness and such female anopheles mosquitoes that spread malaria and thus eliminating these mosquitoes. Modified mosquitoes highlight the potential of biotechnology. Mutant mosquitoes can activate a lethal variation in genes that produce an activator that regulates by overstimulating a protein of its own production. But these decisions can adversely impact conservation.
Many fragile ecosystems are threatened by invasive species like Lantana camara in Sal forests and prosopis juliflora in dry degraded deciduous forests. Would a gene derived species seriously impact the local wildlife than a pesticide to control pests of agriculture for plantation of tree species?
Hence, gene derived technologies bring before us all our past failure of ecosystem engineering as it should. One worries that we will simply see new versions of toads to control paste in sugarcane. Additional advanced technologies are already on the way to safeguard such as DNA enclosed mechanisms to block or even reverse drives in a population. It is reiterated that education is crucial for our decision that we make regarding application of technology on living beings. We end by stepping back to the deeper and more inspirational lessons from looking into the working of life.
The final frontier of genetic engineering will be the possibility of improving human intelligence and memory. Unlike heights, mental skills are beneficial in more than just a positional way. If everyone or even a fraction of the population becomes smarter, it will make society better off. But of all the complex mental skills, wisdom may be the most elusive. Understanding the components of wisdom might require us to understand consciousness. Ingenuity without wisdom is dangerous.
But the vital question in genetic engineering is who should decide? Broad public discussion at world level may be required to draw a line of gene editing. Then emerges, the question of bio ethics. The bromide for calling for greater social discussion is who should decide how gene editing tools should be used. There are two modern foundations either for John Rawl’s Theory of Justice or Robert Nozick’s Anarchy, State and Utopia, that emphasised the moral foundation for individual liberty.
The DNA vaccines made it possible for the genetic material to be inserted into human cells to produce components of a virus which can stimulate genetic code of the component as DNA or RNA. The cells thus can become a vaccine manufacturing facility. But given all the potential of genetic engineering, there is immense uncertainty and danger of bringing drastic dangerous changes in the ecosystem to which all living beings, including humans, are a part and parcel.
(The author is a retired Indian Forest Service officer)
