Science-fiction used to be more fiction than science but now with crazy new advancement such as Elon Musk’s car in space and self-driving taxis in Silicon Valley, it seems as if we might be living in those comic book realities. However, one thing that isn’t discussed as much is creating enhanced humans using gene modifications.
Gene editing isn’t a new technology. Indeed it has been happening for thousands of years through selective breeding – the exploitation of favourable mutations over time to become hereditary traits. Such as, adding beta-carotene to golden rice or changing carrots from purple to orange. CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)-cas9 (the associated enzyme) is the most cost-effective and efficient modern method to accomplish this.
CRISPR-cas9, evolved from the IscB family1 (encoded by ‘jumping genes’ found in alga chloroplasts), makes targeted cuts in a cell’s DNA using specific RNA as a guidance system. Nuclease proteins are then used to repair the frayed ends and join the sequence together again under a chosen repair process. This process – Homology Directed Repair – was discovered by Doudna and Carpentier to avoid mistakes in joining the genome. I must note that there is currently a legal battle over the patents to use CRISPR in human genomes between the two mentioned above and a Chinese scientist called Dr Zhang. Whether this is due to the scientific community side-lining female accomplishments, as they have done so historically (e.g. Rosalind Franklin, Lisa Meitner), or just due to greed over who had the billion-dollar patent granted first, is food for thought.
This ground-breaking work by these two women is still being investigated as the possibilities are endless – from manipulating fruit to have higher yields to stopping malaria mosquitoes The first CRISPR-edited food, tomatoes2, went on sale this year in Japan. They contain high levels of an amino acid believed to aid relaxation and lower blood pressure. Crop breeding just relying on naturally occurring mutations is no longer sustainable, driving a biotech agriculture revolution.
CRISPR’s toolbox goes beyond fruits and vegetables with new therapeutic innovations being released every year. Some studies are looking at tackling muscular dystrophy, restoring vision loss and curing sickle-cell anaemia. With DNA being the next silicon, there’s a worry of producing a ‘gene gap’ – similar to the wealth gap but with access to healthcare. Scientists fear CRISPR could enable humans to play God by enhancing offspring to create ‘designer babies’ or superhuman soldiers. Imagine being able to increase the amount of oxygen to the developing brain to improve intelligence and muscle strength. Or even knocking out the CCR5 gene for cortical plasticity and enhanced memory – a link we have established since 20163.
The experiments with CRISPR have been overtaking international regulatory biotech laws, giving rise to ethical conundrums and potentially disturbing practices. For example, In India, the Biomedical Regulation Bill only implies rules for the CRISPR but with no explicit mention of the term ‘gene editing’. In 2018, a Chinese scientist has already been imprisoned for tailoring twin baby girls4 in-embryo* to grant them immunity to HIV and contribute to the global effort to eradicate the disease. Even though the thought behind the experiment was somewhat altruistic, the methodology and testing were far from acceptable. Since the human genome is so fragile and not fully understood, volatile experimenting on it can result in irreversible damaging consequences. Zhang’s experiment may have left a stain on CRISPR but maybe it was inevitable one. Mankind has always been wary new science – just look at IVF treatments which attached the stigma of test-tube babies, or even the recent COVID vaccine where there is still a large population who are anti-vaxxers.
Despite, the major leaps in genetic engineering technology, the field is still in its infancy. We can expect the major improvements over the next few years to handle the delivery of CRISPR into the human body in a targeted manner and stretching the capabilities to see more diverse modifications.
Regardless, CRISPR is a powerful technology for the future and could one day make science-fiction a reality. But do we have the responsibility to wield the tool that could allow us to determine our own evolution?
*Editing the genome in-embryo means that it will affect the germline and therefore this mutation (and any unintentional others) can be passed on to future generations