The Science Behind: CRISPR
What is CRISPR?
CRISPR (pronounced as ‘crisper’), short for CRISPR-Cas9 (CRISPR-associated protein 9), is a gene/genome editing tool that can alter DNA. Before it was published in 2012, other methods of editing could cost hundreds to thousands of dollars but thankfully, CRISPR is cheap and precise. The appetising name stands for Clustered Regularly Interspaced Short Palindromic Repeats, but what does all of that mean?
How It Works
Genomes can be described as a genetic blueprint with information of the organism and what it needs to function. These can be found in chromosomes which are long molecules of DNA.
CRISPR is adapted from a natural genome editing system in bacteria where bacteria grabs bugs of DNA from invading viruses, turning that DNA into CRISPR arrays (RNA with spacers) that let the bacteria recognise the viruses. This lets the bacteria target the virus’ DNA if it invades again and use an enzyme to cut it apart, disabling the virus. This can be simplified into three steps: Adaptation (bacteria DNA is processed), Production (turning the DNA info CRISPR arrays) and finally, Targeting (recognising and cutting up DNA)
This method works similarly in a lab where the RNA made by researchers would recognise selected segments of DNA and use an enzyme, mostly the enzyme Cas9, to cut the DNA at the targeted location. The selected segment can be entirely deleted or replaced to change the DNA.
What could it do?
CRISPR could cure diseases like cancer or blood disorders and even hereditary blindness by changing genes responsible for these diseases like immune T cells (cancer).
Despite its miraculous nature, CRISPR can stir up concern which is normal for new technology like this. Many are wary of the ethics of such a powerful tool especially with the announcement of twin girls with edited genomes in 2018, perpetuating the ‘designer babies’ fear.
Overall, CRISPR is a revolutionary tool which can (and has already started to) innovate not just the medical industry, but industries like agriculture.
Let’s look forward to its future together!