Reworking the Thread of Life: Promises and Realities of Gene Editing Embryos

Genetic engineering has been a common practice since the start of agriculture. Through selective breeding, farmers have been able to produce desirable traits for plants and animals, while building the framework for generations of scientists. From Gregor Mendel discovering the fundamental laws of inheritance to the completion of the Human Genome Project, farmers and breeders have created a path for scientists to learn about genetic makeup, and answer a crucial question. What makes humans, humans?

Once scientists were able to unravel the entire human genome sequence, telling us what each gene is responsible for, they are now trying to rewrite it. With advances in technology, such as CRISPR-Cas9 (Clustered Regularly Interspersed Short Palindromic Repeats), which gives scientists the ability to delete, insert or replace genes with extreme precision, accuracy and effectiveness. There are three major parts to this system: the cutting enzyme, Cas9; guide RNA, to guide Cas9; and the DNA to be cut. The guide RNA is able to direct Cas9 by having a specific sequence, in this case the repeat that gives CRISPR its name, which complements a portion of the target DNA. Not only can this relatively inexpensive technology be applied to correct defects in human cells, that cause severe conditions, but it can also be used to alter plant and animal genomes to boost food production and reduce the effect of insect-spread diseases. Now, this seems like an excellent idea. It is cheap. It is effective. It is easily accessible.

So, why is it a trending debate topic?

Image that shows how gene editing is done through the CRISPR/Cas9 Process

It is because we want to implement this technology to make embryos who have genetic mutations, or conditions, healthier. We now have the technology to identify significant genetic conditions before the baby is born through ultrasounds, and imaging. Using the gene-editing tool known as CRISPR-Cas9, researchers have successfully edited disease-causing mutations out of viable human embryos. Essentially, it specifically slices a part of your DNA that is causing the genetic mutation or condition, and replaces it with a healthy gene. Gene editing embryos is bringing us one step closer towards a healthier future generation. This gene editing technology should be used on human embryos, as long as there is consent, and the procedure is being followed through ethically. While this technology facilitates what would have been thought of as medical miracles in the past, the widespread implementation of CRISPR does carry significant risk, and the possible benefits to humanity are simply too numerous to ignore. In essence, if appropriately regulated, gene editing on embryos should be allowed to be performed and researched.
The most prominent argument against gene editing is that it constitutes an unacceptable risk to future generations, and that we don’t know “too much” about CRISPR-Cas9 and how it can affect the unborn child. In Marcy Darnovsky’s article, CON: DO NOT OPEN THE DOOR TO EDITING GENES IN FUTURE HUMANS (really interesting article! Check it out!) made a point that not knowing enough about the gene editing technology is why we should not further pursue it. This idea is limiting our scientific exploration and research, while causing social, economic and political issues. Banning embryo gene editing could put a halt on advanced medical research and instead drive the practice underground to black markets and uncontrolled medical tourism, which are fraught with much greater risk and misapplication.

On the other hand, the problem of the child’s consent was brought up by Francis Collins, director of the National Institutes of Health. He said that “Ethical issues presented by altering the germline in a way that affects the next generation without their consent.” Think about this. When liability forms are filled out by a minor, are they the only ones allowed to sign? When a minor has a medical injury, who has the final say on their medical decisions? In general, children lack the legal, moral, and practical ability to provide freely given informed consent. Newborn babies, for example, are not able to consent to the various medical treatments they receive in hospitals — including, sometimes, experimental treatments for rare or difficult-to-treat conditions. Experimental therapies may be justified for children when such therapies are medically necessary for them, even though the children cannot consent to the risks.

Properly understood, then, the question is not about consent but about whether and how the well-being of future generations ought to enter into medical decisions.The transformation of genome editing technologies in the last few years has also taught us a tremendous amount about scientific progress. Arguably, the rapid pace of this field has been driven as much by the scientists who have quickly shared results, protocols, and reagents with the community, as it has been driven by the facile nature of the new technologies.

So, after reading this blog post: what are the next steps, and how can you apply it to this committee?

We want to see the committee consider the advantages AND disadvantages of genomic medicine and gene editing. Talking about gene editing in embryos, is a possibility for the future, and if you read Henry's article, has even happened in today's scientific landscape.

Feel free to comment any questions you may have, discussion ideas, and what you think are some of the pros and cons of using gene editing technologies on embryos.