by Patrick Griffin
figures by Olivia Foster
Wincing slightly, Josiah Zayner depressed the plunger of the syringe in his right hand. “This will modify my genes to give me bigger muscles,” he told the crowd—attendees of a biotechnology conference in San Francisco last October. They nervously laughed and then applauded, having witnessed the first instance of someone trying to edit their own genome using a technology called CRISPR.
People have always dreamed that they could change who they are—not just superficially but the very essence of their being. Zayner’s experiment seems to be a step in that direction, foreshadowing a time when people will modify their genomes to improve or alter themselves. “This is the first time in the history of the Earth,” he wrote on his blog, “that humans are no longer slaves to the genetics they are born with.”
But did Zayner’s experiment even work? And if not, how far-off is such a brave new world really? While some in a movement of renegade citizen-scientists, called biohackers, are eager to use CRISPR for self-improvement, others are more skeptical and point to the considerable challenges and dangers inherent in genome engineering.
What is CRISPR?
CRISPR is a revolutionary tool that enables scientists to edit genetic sequences with extreme precision. It works as a two-part machine: a molecular address (the CRISPR “guide”) and a scissor-like protein (Cas9) that, when delivered into a cell, searches the genome for a unique DNA sequence. Once found, the CRISPR machinery makes cuts and nicks in the DNA that permanently alter the cell’s genetic makeup. This ability, combined with our ever-increasing understanding of how DNA determines who we are, has seemingly unlimited potential.
As demonstrated by its success in animals, CRISPR will be a godsend for those with genetic conditions. Reversing deafness, curing genetic blindness, relieving symptoms of sickle cell anemia: the results in mice have been extraordinary. With human trials already underway in China, and several slated to start in Europe and the US this year, researchers from around the world are now tackling diseases long-thought to be incurable.
But like other great scientific advances before it, there are people who wish to take CRISPR out of the clinic and use it to make themselves better in some way. Many belong to a community of biohackers, and they have a reputation for using technology in new and unconventional ways.
Who are biohackers?
Borrowing from the traditional hacking ethos, biohackers often ignore established safety measures and scientific mores while advocating for the democratization of science. The movement ranges from the innocuous DIY biologist of Brooklyn, performing modest experiments to promote science literacy, to the more extreme cyberpunks and grinders that advocate using technology to improve natural human capabilities.
A proponent of using biotechnology to improve oneself, Josiah Zayner is the CEO-founder of The Odin, a company that sells DIY CRISPR kits online. Having obtained his Ph.D. from the University of Chicago in biophysics, he is certainly no scientific outsider. Yet his attitude toward science is steadfastly that of a biohacker, stating on his blog, “I am sure many people will try and dismiss this as unscientific or how clinical trials will need to be run. The problem is that old world is dead.”
And while it’s tempting to dismiss him, there is increasing evidence that he is not the only one that thinks this way. In the past couple years, two other biotech CEOs, Liz Parrish and Brian Hanley, have made news by receiving gene-based anti-aging therapy, paving the way for further self-experimentation using CRISPR.
The limits of current CRISPR technology
At least for now, the feasibility of such an application of CRISPR is restricted by practical and technological limitations. For example, Zayner’s experiment illustrates that it is still difficult to get CRISPR into human cells efficiently. His plan was to edit a gene that inhibits muscle growth—called myostatin—by injecting a ring of DNA harboring the CRISPR machinery into his veins. In theory, this simple application would transport some of the DNA into some of his muscle cells, yet he would probably be better off hitting the gym. While this may work for cells in a dish, the complexity of using this technique does not scale for an entire human being. Thus, this way of delivering CRISPR is highly unlikely to modify enough cells to make any discernible difference (as even Zayner admits on his blog).
The problem of delivery is not irresolvable though, and there are many scientists pioneering new ways to get CRISPR into cells. Just recently, a group of researchers at The Salk Institute were able to deliver CRISPR into the legs of mice using a virus, which substantially increased muscle growth. (It should be noted that their ultimate goal was to use CRISPR for therapeutic purposes, not to make Mighty Mouse.)
Even if the delivery problem is solved, biohacking with CRISPR faces other challenges and questions (Figure 1). How can we edit every cell in the body? Alternatively, can we target editing to specific tissues or organs (e.g. muscle, brain, or kidney)? Furthermore, even knowing what gene to change is a problem that requires substantial investigation. Biology is complicated and, although it may not be obvious in every case, mice and men are not the same organism. Therefore, simply showing that an edit is effective and safe in a model organism is not enough to justify making the same change in humans; what could be beneficial to a mouse may be harmful to a person.
The ethics of CRISPR and biohacking
While there are many hurdles to using CRISPR on humans (for any purpose), those issues will likely be resolved one day, which would present serious ethical dilemmas (Figure 2). Should it be legal to edit your own genome? Moreover, is it moral? And what if the ability to edit oneself is prohibitively expensive (à la plastic surgery)? It is easy to imagine a world where only the rich can alter their genomes or those of their children. Do you want to be especially smart, strong, or good-looking? Pay up.
Perhaps equally dystopian is a scenario in which genome editing becomes so cheap and easy that people could afford to alter themselves as easily as if they were getting a tattoo. In a world where people routinely alter the color of their eyes, size of their muscles, or even genes that affect their neurobiology, what constitutes someone’s identity?
The future of CRISPR and biohacking
While these scenarios may sound like something out of an H.G. Wells novel, there is no reason to believe they are impossible. Therefore, it is not a question of if, but when CRISPR will be a plausible option for self-improvement.
Luckily, there is still some time before that day comes. In a recent interview with author Sam Harris on his podcast “Waking Up,” one of CRISPR’s foremost pioneers, Dr. Jennifer Doudna, cautioned that a scenario where CRISPR is used for self-improvement “…is frankly not coming any time soon.” She also noted that, “The thing I worry about the most is primarily just people getting out ahead of the technology itself.”
Josiah Zayner may be the best example yet of someone getting out ahead of CRISPR technology. And yet, while he may not have given himself bigger muscles, his experiment might have succeeded in one sense—it has forced people to confront the dangers and dilemmas of biohacking in the age of CRISPR.
Patrick Griffin is a Ph.D. student in the Biological and Biomedical Sciences program at Harvard University.