Cut to the chase: the future of gene editing

Blonde hair, blue eyes, tall and intelligent; a cutting-edge technology is making the prospect of genetically engineering human babies more of a reality, but should we fear a perfect human race?

Many years ago, I used scissors to cut cardboard to build a diorama for grade 4 show-and-tell. The result was unspectacular. Hence, I found myself, ten years on, studying in a laboratory not an art studio. Unless you are exploring the guts of a rat, the precise cut of the classroom scissors hitherto lacked scientific significance.

In 2017, scientists have been hastily examining the use of a novel technology that is comparable to a pair of molecular scissors.

But have prudence, rather than slashing your finger, these scissors can snip your DNA.

Cut and paste. Just like scissors, CRISPR can completely rearrange one’s DNA. Source: Wikimedia

Colleagues Emmanuelle Charpentier and Jennifer Doudna are responsible for the genesis of this powerful gene editing tool. The technology is named after DNA sites titled clustered regularly interspaced short palindromic repeats.

What a mouthful. Let’s go with the moniker CRISPR.

Like scissors, CRISPR can easily incise and remove a part of the DNA sequence. Removing DNA creates a mutation that disables a gene or set of genes. When the location of a gene is known, such as the gene for Cystic Fibrosis, the gene can be incised to prevent manifestation of this disease.

Fundamental to this system is the protein Cas9. Cas9 acts to cut and degrade viral DNA. A virus invades a host cell by injecting its DNA into the cell. The CRISPR tool can cut fragments of this viral DNA and reintegrate them into the host cell DNA, at the aforementioned (unenunciable) sites. Whilst it seems counterproductive to integrate viral DNA into the host cell, CRISPR consequently creates a chronicle of which viruses the cell has been exposed to.

“CRISPR is effectively a genetic vaccination card in cells” 

Blake Wiedenheft: member of CRISPR production team

Powerful, huh?

By precisely altering human DNA, CRISPR could potentially extend into the realm of enhancing traits that are deemed to be socially desirable. Cue the ‘designer baby’.

Whilst we are all unique, our DNA is simply the product of four letters. A, T, C and G. Cut them up, rearrange them and write a new sentence. This sentence reads a different skin colour, height, IQ and predisposition to alcoholism. CRISPR can (potentially!) do this.

Does CRISPR promote the perfect human race? Source: Wikimedia.

The fate of CRISPR is unknown. Are these six capital letters perilous or promising? Could we see greater inequality? Genetically doped athletes? Eradicate malaria-transmitting mosquitos? Reduced trait variability? Improved food production?

CRISPR poses unprecedented ethical implications.

Esteemed Australian bioethicist Julian Savulescu argues that we have an ethical obligation to create the best human race. “You alter the genetic makeup of your future baby when you smoke or drink alcohol… why should we treat a genetic mechanism differently?”

Yet, in its current state of unknown potential, it is unlikely that the experts in positions of responsibility will have uniting beliefs on how CRISPR should be utilized. The current state of CRISPR is a paragon of the limitations that ethics poses in the production of knowledge. How can scientists advance if they are confined by ethical boundaries?

If you want to play real-life Sims, it is only $1352 to purchase 75µg of the CRISPR-cas9 complex. Aye, we will let the experts show us the genuine capability of the proverbial molecular scissors that we call CRISPR.

3 Responses to “Cut to the chase: the future of gene editing”

  1. Emma Fazzino says:

    Great piece! I love the analogy of the scissors and the title works well too. I think you ‘re writing is quite accessible for those with a biology background, so if they were your intended audience then you have done well!

  2. Hockey says:

    Thanks for the comment Jamie!
    Yes, this is a complex topic that is still gaining understanding. I was hoping to convey simplicity in writing without disrespecting the science of the technology.

    After the viral DNA is inserted into the CRISPR sites on the host DNA, the cell makes an RNA copy that is a replica of the viral DNA. This RNA forms a complex with Cas9 and searches the cell for the matching viral DNA sequence. If the viral DNA is present, the complex binds and Cas9 cuts it out! With the virus gone, the cell then naturally repairs the break in DNA.

    By programming what sequence the CRISPR-Cas9 complex searches for, this process can be manipulated to remove whatever genes we want! And that is where we dive into the realm of genetic engineering.

    Importantly, the ‘vaccination card’ is heritable, that being, it is passed onto the cell’s offspring, so all future cells carry this immunity.

    Hopefully that is the extension that you were looking for. Thanks again!

  3. Jamie says:

    Great article, Isaac! The potential of CRISPR is indeed as exciting as it is ethically ambiguous. Love the choice of quotes. Perhaps you could expand on the “creates a chronicle of which viruses the cell has been exposed to” aspect of CRISPR a little more. You could do this by extending the wonderful analogy you chose (“genetic vaccination card”) to make it more comprehensible for the average reader. I found myself questioning how exactly it acted as a vaccination card, but that could just be me!