World's First Gene-Edited Babies Shock the World
Last Monday, Dr He Jiankui stupefied the world when he announced that he successfully edited the genome of two, healthy baby twins. While many scientists (myself included), could only dream of a better, positive world where health issues can be readily solved notably through gene editing, there is an Everest of obstacles that have to be yet surmounted to reach such success without detrimental off-target effects.
Wait a minute! I believe I am getting way ahead of myself. Since this blog is intended to enlighten EVERYONE on the current scientific innovations that will lead us to optimal healthspan, I must take you all to the very beginning. So what's exactly the big deal about these news and why does it represent such controversial case? Allow me to give you an extremely brief and overly simplified view of genetics (you are free to skip the next paragraph if you are familiar with the concept of basic genetics).
The human genome accounts for 20 000 to 25 000 genes that serve different roles in the maintenance of a healthy, happy body. The genes are stored within our cells on 24 pairs of chromosomes and have each a specific size and location (or locus if you want to be scientifically accurate). A chromosome itself represents a long strand of DNA that is usually seen in its condensed form through a karyotype. Thus, the genes are the distinct segments on that long strand of DNA. There are four bases- A T G C - that pair with each other (A with T and G with C) and their different combinations give rise to the different genes. These genes are pretty much coding for different proteins and functional molecules. The regulated expression of these genes is responsible not only for your hair colour or susceptibility to acne, but also for other regulatory molecules of gene expression and a variety of molecules essential for cell viability.
It was one of those cellular components that was presumably successfully edited out of the healthy babies. (I say "presumably" as we have no evidence for the off target effects that this gene editing could have had on the rest of the genome). The component in question is the CCR5 receptor essential for the attachment of the HIV virus to the T-cells (immune cells that are the key players in the infectious cascade resulting from the viral invasion). Without this receptor, the HIV virus simply cannot invade the immune cells and dismantle the individual's immune system.
Dr He Jiankui and his team used the CRISPR-Cas9 gene editing system that can excise genetic content like scissors (we will talk more about CRISPR system in another post). He then implanted the embryos in seven different women. One of these women gave birth to the twins, Lulu and Nana. So far, this scenario reminded me of the Brazilian telenovela "The Clone" (a must-see show btw) in which Dr. Albieri transformed an ovule with the genetic material of his late godson. While the doctor and founder of Direct Genomics denied the safety of gene therapies in human organisms, he suddenly announced his big project to the world at the International Human Genome Editing Summit in Hong Kong.
“I truly believe that, not only for this case but for millions of children, they need this protection since an HIV vaccine is not available. For this case I feel proud.”
-Dr He Jiankui
But wait! There is more! Apparently, the current investigation revealed that the doctor engaged in a parallel research on abandoned embryos in collaboration with researchers from the Luohu People's Hospital. This information came from a database belonging to the World Health Organization. In realty, over 400 abandoned embryos were included in this project that was approved by the Medical Ethics Committee at the Luohu People's Hospital in Shenzhen in June 2017. The document providing evidence for this agreement supports that the research was oriented towards evaluating the safety of gene-therapies in gene-associated diseases and even infertility!
With all this being said, we can now understand why these news seriously shook the world. Can you imagine a world in which the HIV virus is prevented from destroying people's lives simply by making them resistant to its invasion? After all, many of the therapies against the virus have previously failed mainly because the virus itself mutates too fast to maintain a cellular component that could become a target for destruction.
On the other hand of this optimistic perspective, there are several factors that could be more detrimental than beneficial to the babies. For instance, Dr He claimed that only one of the copies for the CCR5 genes was suppressed in one of the babies. This means that the other copy is still functional and does not confer any resistance to the HIV virus. In addition, there is absolutely no way to determine whether this manipulation could affect other pathways in the body and ultimately the health of the babies. Dr He himself supports that the girls will have to be under observation for the next 18 years of their lives.
“It is impossible to overstate how irresponsible, unethical and dangerous this is at the moment. There was a worrying lack of oversight or scrutiny of his clinical plans before he started human experiments and a complete lack of transparency throughout the process.”
- Kathy Niakan, scientist at the Francis Crick Institute, London
Let us not ignore the fact that this experiment breached entirely a ban on human genetic manipulation that was implemented in 2003 in Shenzhen. There is actually a tremendous gap between modelling disease in animal organisms and translating them to human models. Most importantly, this research lacks the reproducibility criteria of every scientific experimental design. And these claims have yet to be peer-reviewed by the legitimate scientific community.
Ultimately, there is a scientific method that needs to be followed under all circumstances. Despite his or her ambition to improve healthcare and solve a core scientific issue, a scientist had the unshakable duty to remain transparent in the scientific community and to account for the unwanted effects on an experimental therapy. However, if Albieri did not circumvent the boundaries of his own scientific community, would he have been able to achieve his own incredible breakthrough? There is a fine balance between innovation and pandemonium in science. And while we always strive for the first, we need to do everything within our capabilities to keep the latter at bay.
Take a look at this video that sums up the entire issue:
What do you guys think about the concept of gene therapy to eradicate or prevent a disease?
Start the conversation in the comments section down below!