The Gene-Editing Revolution Is Already Here
Ever since the discovery of the structure of DNA in the 1950s, scientists have dreamed of rewriting the code of life. The possibility of correcting genetic mutations that cause disease to significantly improve human health has been a longstanding aspiration.
CRISPR-Cas9, derived from the natural immune system of bacteria against viruses, is a revolutionary tool that offers the real potential to achieve what was once thought impossible, quickly and efficiently. Since its adoption in 2012, CRISPR technology has rapidly transformed various fields such as basic research, drug development, diagnostics, and agriculture. It has become a mainstream topic of conversation, inspiring Hollywood scripts, and serving as the standard global genome-editing tool. As we enter a new decade, it is evident that CRISPR-based applications will play a significant role in addressing societal challenges, including disease, food production, and environmental sustainability.
Almost a year ago, scientist He Jiankui shocked the world by announcing that he had edited the embryos of twin girls. This medically unnecessary experiment blatantly violated the global consensus against current clinical use of CRISPR in human germline editing—making genetic changes that can be inherited by future generations. In response, the scientific community has redoubled efforts to establish stronger safeguards, encourage a more cautious approach, and deepen public discourse on responsible use. The World Health Organization is now urging government regulators to take action. Rather than imposing a moratorium, compliance is essential as it promotes conversation—a critical aspect considering the persistent interest in editing the human germline.
As CRISPR enters its adolescent years, we aim to broaden the scope of edits we can make, focus on advancing the safe and effective delivery of CRISPR genome-engineering tools, navigate the initial wave of Food and Drug Administration approvals, and delve deeper into naturally occurring mechanisms to enhance the accuracy of CRISPR-based editing.
There is a possible future where genetic diseases become a thing of the past, where DNA sequencing and treatment for harmful mutations become routine outpatient procedures. However, we must ensure that in this future, everyone has access to these new technologies, and there is a consensus on rules and regulations governing the application of this technology to the human germline. Achieving this requires collaborative efforts that include increased private and public investment, expanded commercial partnerships to mitigate financial risks and scale the technology, and political and regulatory considerations that enable widespread affordable access to safe and effective cures, without stifling a technology that will underpin the health of future generations.
CRISPR May Work On Way More Diseases Than We Think
Now, CRISPR is one of those new genetic technologies that has the potential to radically change the way we treat diseases. It enables scientists to edit DNA with an unprecedented precision and efficiency, offering the possibility of permanently removing aberrant genes responsible for diseases like sickle cell anaemia and cancer-causing mutations.
Traditionally, CRISPR has focused on modifying DNA, resulting in permanent changes to the genes within a cell. However, in a groundbreaking paper published in Science, researchers have now demonstrated the first use of CRISPR on a more transient basis. Instead of altering DNA, they utilized CRISPR to modify RNA, which serves as the genetic material derived from DNA and is involved in the production of proteins, enzymes, and other essential biological components of the human body.
By harnessing the power and precision of CRISPR for RNA, the potential for genetic editing to treat diseases expands significantly. Current methods of modifying RNA are inefficient and lack the level of control that CRISPR offers. With CRISPR, researchers can target specific segments of RNA and remove them, opening up the possibility of replacing some daily or weekly drug regimens with CRISPR RNA-based therapies that only need to be administered once a month or so.
A Powerful New Tool for ‘Editing’ the Human Genome
It would hardly be an exaggeration to say that inside a nondescript office in London on Feb. 1, a small group of scientists and patient advocates made a decision that could potentially change the future of humanity. Since 2012, scientists have been experimenting with CRISPR-Cas9, a powerful tool that functions as an editor for DNA, allowing them to identify and correct mutations that can lead to deadly diseases. Now, for the first time, a researcher has received the green light to test this tool on viable human embryos. Kathy Niakan is expected to begin trials at the Francis Crick Institute, known as the Crick, in London in the coming months.
While scientists have manipulated the genomes of various animal species, no sanctioned studies involving human embryos have been conducted using CRISPR. Last year, Chinese researchers reported conducting experiments on human embryos, prompting calls for a temporary worldwide moratorium on the use of CRISPR on germline cells, specifically those derived from human embryos, eggs, or sperm. The precision, efficiency, affordability, and user-friendly nature of CRISPR, in contrast to other gene-editing techniques, have made its use concerning to some. This is what makes the Feb. 1 decision issued by the U.K.’s Human Fertilisation and Embryology Authority (HFEA) so groundbreaking and controversial. Depending on one’s perspective, CRISPR can be seen as a medical marvel with the potential to cure diseases such as sickle-cell anemia, Alzheimer’s, and even cancer, or as a science-fiction nightmare waiting to unfold.
“We now have a highly efficient method that enables us to make precise and specific alterations to the DNA sequence. This allows us to explore the function of genes and determine which ones are necessary for healthy development,” says Jennifer Doudna, a professor of chemistry and molecular and cell biology at the University of California, Berkeley, who played a crucial role in developing CRISPR. However, the fact that CRISPR enables scientists to permanently alter the human genome of embryos makes some scientists uneasy. J. Craig Venter, a co-mapper of the human genome, states, “I do not think we are ready to edit human embryos yet. We have limited knowledge of how changing the genetic code will impact development. Only a small percentage of genes are well understood, and for most, we have little or no understanding of their role.”
Doudna supports Niakan’s study, but only because the embryos are not being brought to term. “I don’t think it’s appropriate or responsible to use CRISPR on embryos that would be implanted in people right now,” she says, highlighting the numerous unknowns about the long-term effects of manipulating human genes.
The manipulation of the human genome also raises ethical questions regarding which parts of the DNA should be altered. Should genes associated with non-life-threatening conditions that impact quality of life, such as asthma or severe allergies, be edited out? What about genes linked to a predisposition for obesity or having red hair and freckles?
Here’s Another Way CRISPR Is Changing Medicine
Gene editing, using the CRISPR technology, has the ability to edit DNA with the same ease as a word processor edits text. This system is now being utilized for the diagnosis of cancer and the creation of rapid tests for infections such as the Zika virus.
CRISPR-Cas9, initially described in 2012, provides scientists with a genetic tool comparable to a word processing cursor, enabling them to precisely target specific sections of a genome in order to delete, insert, copy, cut, or paste DNA as desired.
“This new CRISPR-based platform has the potential to be developed into a point-of-care diagnostic that could be as user-friendly as an at-home pregnancy test,” says James Collins, a member of the Broad Institute and a professor of engineering at MIT.
© 2024 Lion Heart Healthcare Company, Hasan Arslanyuregi
