A Crack in Creation summary

Before we dive headfirst into the biological details of gene editing, it’s helpful to have a short recap on the scientific language involved. First, there’s the genome, which refers to the complete set of genetic information contained within our cells. The genome determines our physical characteristics like height, skin color and even susceptibility to disease.

The genome itself is made up of deoxyribonucleic acid, more commonly known as DNA, a molecule that consists of four chemical groups: adenine, or A; guanine, or G; cytosine, or C and thymine, or T. In this sense, A, G, C and T are the four letters of the genetic language.

So, now you know that CRISPRs are the key to simple, effective gene editing – but what exactly are they?

In a nutshell, they are regions of bacterial DNA characterized by exact repetitions of genetic sequences. In between these repetitions are similarly-sized lines of DNA known as spacer sequences.

You now know about the CRISPR cutting machine, but there are quite a lot of technical concepts and terms to take in. So, let’s give it a quick recap:

Given a piece of CRISPR DNA, the CRISPR RNA associated with this genetic sequence can guide the cutting protein produced by the Cas9 gene to a location in foreign DNA. This location would be one that precisely matches one of the spacer sequences in the original CRISPR DNA. This Cas9 protein then cuts out the matching piece and, with its work done, is led away by its guide RNA.

The CRISPR gene editing method opened up a wide new world of opportunities; after all, the prospect of controlling the human genome broke down any and all limits to human imagination in gene engineering.

Could scientists now simply make woolly mammoths or unicorns?

Did you know that there are over 7,000 human genetic diseases that are caused by the mutation of just a single gene each?

It’s a shocking statistic, but thankfully, CRISPRs can be used to identify cures to many of these ailments. In fact, now that science has a cheap and easy-to-use genetic editing tool at its fingertips, we could soon see the rise of precise genetic therapies that usher in a new era of medicine.

In 2014, just two years after the author and her colleague made their breakthrough discovery, public excitement about CRISPR was on the rise. Around the same time, an up-and-coming entrepreneur approached the coauthor, Samuel Sternberg – who was then a PhD student of the author’s – with an offer: would she like to join a start-up that would offer couples the first “CRISPR baby.”

Sternberg declined the proposition, but it raised serious questions nonetheless. Had gene editing become too easy and accessible? Which ethical questions were at stake with the development of this technology?

So, there’s a lot of thinking that needs to be done before gene editing moves forward and, at the moment, there are a few contending opinions. For example, while the National Institutes of Health, in accordance with directives from the Barack Obama administration, called for a suspension of all research involving gene editing of human embryos, others have argued that such research should be aggressively pursued.

It’s complicated terrain, but for the author, there are three general themes to consider before taking any decisions on whether human gene editing should be pursued: safety, ethics and regulation.