A shot at a perfect society
Crispr/Cas9
Scientists have discovered a way to adjust bacterial immune machinery to create a gene editing tool that can search for genes. They similarly found a way to manipulate the enzyme called Cas9 used in bacteria in order to insert new DNA into genes. 4 By combining these two methods, scientists are able to change the way that the DNA is structured. This method is known as CRISPR Cas9. CRISPR Cas9 edits genes by precisely cutting DNA and then letting natural DNA repair processes take over. The system consists of two parts: the Cas9 enzyme and a guide RNA. Cas9 acts as scissors, able to cut the DNA strand into two pieces. The guide RNA can read the DNA strand and find the wanted genes. The CRISPR Cas9 has 3 modes of action it can apply to a DNA strand: disruptions, deletions and corrections. 5 Disruptions lead to a single cut that is reformed by addition of more nucleotides. The cell will now recognize this gene as inactive and cease production of the associated protein. Deletions cut at two different sites, leading to a deletion of the intervening sequence. Corrections add a DNA template alongside the CRISPR/Cas9 machinery which allows the cell to correct a gene, or even insert a new gene. Going back to the example of sickle cell disease, this could lead to the removal of the gene producing the faulty protein and replace it with a working haemoglobin molecule. In fact, at the Institut Imagine in Paris, a project led by Professor Marina Cavazzana - GENE FOR CURE - is researching whether it is truly possible. 6 The process involves taking stem cells – a cell with the potential to turn into virtually any cell – from a patient’s own body, treating the faulty genes with CRISPR-Cas9, and then reinserting the altered stem cells into the body to alleviate the symptoms of a genetic disease. Sadly, it is not as easy it sounds. The process of reinserting it into the body is slowed/stopped by the body itself, since it is most often recognized as a pathogen. However, the CRISPR field is evolving at an incredible pace, with the number of peer-reviewed scientific papers with the term CRISPR in the title or abstract increasing by 1,453% since 2011. 7 CRISPR as a valid cure to genetic disease is projected to come soon, with renowned professors such as Naldini ‘expect[ing] a cur e for sickle cell diseases to be found within the next ten years’.
Ethics
The ethics of gene editing are often scrutinized heavily by both public and government. Outside the possibility of treating conditions, genetic editing can be done pre- birth. ‘Designer babies’ are often a term thrown around within these discussions. Changing the baby’s height, hair colour, eye colour to whatever the parent desires. Wouldn’t anyone want their child to be better at learning? Better at sports? Some worr y that taken to its extreme, genetic editing could create classes of individuals defined by the quality of their engineered genome.
Genetic predispositions – a code in the DNA that means that someone who is more vulnerable to a condition suffered by their parents, e.g asthma – could be removed from the child’s DNA. The most controversial
4 See CRISPR Therapeutics 2022. 5 Ibid. 6 See Burke 2019. 7 See Lino et al. 2018.
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