The First CRISPR
In August of 2012, through the study of bacteria, the scientists Jennifer Duodna and Emmanuelle Charpentier discovered that it was possible to engineer a guide strand of RNA to cut into a DNA genome at any stage and replace it with another one. This was the breakthrough revelation of CRISPR/ Cas9. The discovery of this gene editing tool would come to revolutionize science, medicine, agriculture, and other facets of human life. Nothing like this had ever been seen before.
For those who are unfamiliar with CRISPR/ Cas9, CRISPR, which stands for Clustered Regularly Interspaced Short Palindromic Repeats, is a family of DNA sequences found inside prokaryotes (bacteria), which can be used in combination with Cas9 (a type of enzyme that cuts DNA), to edit genes by creating target cuts in a DNA sequence. These cuts can then be replaced by any gene that the scientist chooses. This tool proved to be relatively simple to use and works in basically all organisms with a viable genome. The utility of this technology in treating disease in humans, as many diseases are rooted in genetic defects, was quickly recognized by the scientific community. With this technology, you could cut out whatever broken genes you wanted, and then input a correction. We use CRISPR to edit DNA, the very core of what makes an organism what it is.
Now, in late November of 2018, for the first time in scientific history, a scientist has claimed to have used CRISPR to genetically edit a human embryo through in-vitro fertilization. His work has manifested in the birth of a set of twin girls, who appear to be healthy and completely viable. A third gene-edited baby is also on the way. Chinese scientist He Jiankui of the Southern University of Science and Technology in Shenzhen, China, claims that this achievement dates back to work starting about nine months ago. In his statement video, he explains his personal views on what he believes to have achieved and what he thinks it means for science.
Jianku’s actions open up a plethora of ethical, moral, and legal concerns to the world of science and, in general, to life. It is first important to understand the reason why he decided to genetically modify these twins. The father of the soon-to-be CRISPR twins was HIV positive. Jianku aimed to disable the CCR5 gene in the embryo, so the future children would be resistant to potential HIV infection. His justification that the procedure was medically appropriate is that it showcased the “real-world medical value” of CRISPR and its ability to cure disease, as well as prevent these twin girls from ever suffering as their father has.
Nevertheless, what Jianku did was ultimately unnecessary. As of 2018, there are a multitude of ways for an HIV positive parent to conceive a child that does not carry the disease, without modifying the babies’ genomes, cutting out pieces of their DNA, and exposing the embryo to all the associated dangers that come with the process. What Jianku did was nothing more than an experiment-- on humans; he attempted to see whether CRISPR could be used to cure these babies. There was no medical, practical, or scientific necessity to take this route. It seems as if he was simply trying to prove that it could be done and wanted to be the first to do it.
Moreover, Jianku’s work was also performed without the knowledge or approval of his university. He has been on leave since February of 2018, and in a statement from the University, “His conduct in utilizing CRISPR/Cas9 to edit human embryos has seriously violated academic ethics and codes of conduct...” His work is also under review by China’s National Health Commission, in addition to the scrutiny of the world. This opens up another issue in this entire debate. The scientific community has not properly established guidelines on how this technology can be used. Thus, despite the fact that this procedure is not fully understood or accepted, scientists still have the power to perform it, under the radar and without sanction.
Although He Jianku attempts to defend his work, the scientific community has frowned upon his misconduct. A coalition of 122 Chinese scientists wrote a joint statement denouncing him, and CRISPR-co inventor herself, Duodona, says this event only works to further reinforce the need to regulate and confine the usage of this technology on humans. The scientific community sees this as a reckless experiment, which could have had unchartable consequences for the babies if it had failed. Moreover, there may still exist underlying issues from any number of off-target cuts or damages that could have occured in the genome. The possibilities of what could have gone wrong in these babies are truly boundless.
It was just in 2017 that the National Academy of Sciences began to endorse the use of CRISPR on humans, but the number of questions and dangers surrounding its use loomed high. With every use of CRISPR, there is a risk of off-target cuts, incorrect recombination, and other genetic errors that could leave the gene, or embryo, essentially unviable. The science was, and still is, too new and has not been thoroughly explored for a 100% success rate. Additionally, it introduces the practice of using human embryos as model organisms. That means more and more scientists will become lackadaisical in their use of potential human lives, comparable to those of lab mice or flies, discarding failed biological projects into waste buckets during experiments gone wrong or creating mutants if they were ever allowed to actually be born.
We have opened up a daunting chapter in the world of gene editing, one in which we can construct humans to have the exact genetic makeup that we would like. More so, we live in a world where scientists have the ability to use this technology unvetted by strict oversight. Simultaneously, scientists’ understanding of CRISPR and its functionality is increasing quickly and exponentially. Without carefully regulating this boundless tool, I fear we are entering a world where human embryos can be used as model organisms to determine gene functions, and babies can be constructed in a lab, equatable to a genetically modified piece of corn.