China’s CRISPR babies and the Future of Gene-Editing
What’s going on with China’s CRISPR babies?
This past November, Chinese scientist He Jiankui, an associate professor at Shenzhen’s Southern University of Science and Technology, announced that he used the CRISPR/Cas9 construct to edit the genomes of two Chinese twin girls, Lulu and Nana. A preliminary Chinese investigation revealed that Jiankui intentionally avoided government supervision, garnered funds and researchers on his own, and broke government bans against human genome editing (Xinhua).
So, what exactly did Jiankui do? To start off, let’s go over what CRISPR technology entails. CRISPR, or clustered regularly interspaced palindromic repeats, is an engineered guide RNA that binds to a desired DNA sequence. After CRISPR is attached, the Cas9 protein, an endonuclease complexed to CRISPR, cuts at the desired sequence, effectively knocking out the gene. Jiankui’s goal was to disable the CCR5 gene, which codes for a protein that allows HIV to enter helper T cells of the immune system. Yet, disabling the CCR5 gene, crucial in fighting other viruses such as West Nile virus, may leave the twins susceptible to other diseases. Moreover, the role of CCR5 in development is unknown, and other unintentional mutations in the genome may have occurred, potentially affecting the physiology of the two girls (Nature).
Back in 2015, a one year old girl with Leukemia was cured via gene therapy with genetically modified immune cells back in 2015. What makes Jiankui’s edits any different? First, Jiankui’s edits were performed on human embryos, a form of germ-line cell that can be passed onto the next generation. On the other hand, edits to somatic, or body cells, are not as intensely regulated as they do not affect the entire organism. Moreover, Jiankui has run into more legal problems after reports of disguising his research as merely “AIDS vaccine development” and conducting his research without oversight emerged (Popular Mechanics).
Looking ahead, what will come of Jiankui, of the two girls, and of gene editing in the future? Jiankui is currently facing a potential death penalty charge and has been missing for the past two months (Newsweek). Numerous American academics in universities such as Rice and Stanford have also come under fire for potential ties to Jiankui, and it seems unlikely that China’s health ministry will allow He to go through with his initial plan of looking over the twin girls until they turned 18 (Nature). The fate of the twin girls is up in the air, and, for obvious reasons, it looks like the genetic editing of human embryos will be put on hold for quite a while. No one knows exactly the limits of the potential medical benefits brought about by gene editing, but as technology progresses, a plethora of ethical issues similar to those incited by He’s experiment are bound arise as well.