Biohacking and DIY Gene Therapy: Revolution or Hi-tech Snake Oil?

Do you want bigger muscles? Want to make those brown eyes blue? Does your memory resemble a slice of Swiss cheese? Well, step right up and let me tell you about biohacking! Lend me your ears…and I’ll tell you how to improve them! With our new do-it-yourself genetic engineering kits, you can change whatever genes you want!

Bio-savvy entrepreneurs are determined to make biohacking a mainstream activity. Companies are emerging that promote DIY gene therapy, so now anyone with an opposable thumb can pipet DNA changes into their bodies, their pesky little sister, pets, or just about any living creature they encounter.

Wouldn’t you like to be a biohacker too? Or is biohacking just the latest incarnation of snake oil?

Josiah Zayner, who earned his Ph.D. in biophysics in 2013 at the University of Chicago, is founder and CEO of a company called The ODIN. The main objective of the company “is to make biological engineering and genetic design accessible and available to everyone.” Some of the products on the site look downright cool. One kit allows users to produce bioluminescent bacteria. Another kit makes fluorescent brewer’s yeast (which can then be used to brew beer that glows under blacklight).

Those products seem benign compared to Zayner’s ultimate objective: selling genetic engineering tools to the masses so they can modify their own genes, or those of other living creatures, in whatever way they want without any oversight or regulatory approval. Zayner has already initiated experiments on himself and encourages others to join him on this wild ride. In the rambling presentation below, Zayner explains over shots of scotch and F-bombs that he wants to crowdsource genetic engineering because he believes it will facilitate innovation. Why let professional scientists have all the fun? Zayner demonstrated how easy biohacking your genome can be by injecting the reagents into his arm during the presentation and distributing free samples for the audience to take home.

Let’s take a closer look at his idea. Zayner is using CRISPR/Cas9, a powerful new tool for gene editing, to disable his myostatin gene (learn about the basics of CRISPR/Cas9 and its application in gene therapy). Cas9 is a DNA-cutting enzyme that is directed to a specific site in DNA by a guide sequence. Myostatin stops muscles from growing, so his plan is to knockout this gene in his muscle cells in hopes that it will make them grow once again. Given his affinity for scotch, a more useful experiment might have been to enhance his alcohol dehydrogenase genes.

There is evidence linking the depletion of myostatin to muscle growth. Mice engineered to lack myostatin have double their normal skeletal muscle mass. CRISPR/Cas9 has been specifically used to knockout myostatin in animal embryos, such as rabbits, and the genetically modified animals grew to have more muscle mass. Moreover, when humans are born with mutations that lead to less functional myostatin, they also have more muscle mass (or, in less pleasant-sounding medical terms, “gross muscle hypertrophy”).

CRISPR has already been used to successfully modify human embryos (none were implanted), but to date, no one has tried CRISPR/Cas9 in a living adult. Zayner’s strategy is to simply inject plasmid DNA that contains the Cas9 gene along with the guide sequence that directs it to the myostatin gene.

Importantly, he’s produced no evidence yet to show that these reagents work in human cells. Ideally, we’d like to see confirmation of the gene modification in a muscle biopsy from Zayner, or proof that his approach works in an adult animal model. At the very least, it would be useful to know whether his system alters the gene in cultured cells.

So, can this really work? There are some formidable obstacles and shortcomings. First, the injected plasmid DNA has to get into the muscle cells. Many would argue that the DNA is likely to be degraded or damaged along the way. There is scarce evidence that intramuscular injection of DNA works, but I did find one study done in mice from 1993 suggesting it is possible, although expression levels of the gene injected in this mouse study varied. Variations in the levels of Cas9 or the guide sequence would certainly affect the outcome.

Nevertheless, let’s pretend some of it gets into a few muscle cells and they make the Cas9 protein and its guide sequence. The next big assumption we have to make is that the guide sequence used actually cuts the myostatin gene. Multiple guide sequences usually have to be tried to find one that works and, as mentioned above, I’ve seen no evidence that this particular guide sequence operates as it should in human cells.

Additionally, you have two copies (alleles) of myostatin, one from mom and one from dad. To knockout myostatin completely, Cas9 would have to cut both alleles. Let’s assume we get that far and both alleles of myostatin are cut. Sometimes cells can repair the DNA cut without incident. For myostatin to be disabled, the cell would have to make a mistake when repairing the severed DNA (which they do, but not all the time). Assuming we jump all these hurdles, that one cell or handful of cells is not likely to produce any noticeable change in muscle mass, especially if only one allele was disabled. Zayner claims repeated injections might overcome this issue, but given the sheer number of cells that would need to be altered to produce a visible effect, the claim seems to be on very shaky ground.

Despite all the caveats, disrupting a gene is actually the easiest application of CRISPR/Cas9. To add or change a genetic sequence, an additional fragment of DNA needs to be incorporated where Cas9 made the incision. And if you wanted to use CRISPR/Cas9 to give yourself wings or eyes in the back of your head, you can forget about that. We are nowhere close to knowing how to do such things.

More alarming, there is risk of dangerous side-effects. While the loss of myostatin will increase muscle size as well as bone mineral density and bone mass, it also leads to spinal disc degeneration and spinal osteoarthritis. Second, there is a risk of infection or an allergic reaction to the injections. Third, CRISPR/Cas9 has been reported to produce so-called “off-target” effects. In other words, the guide sequence sometimes escorts Cas9 to other places in the genome, where it may introduce cuts in genes that were not intended to be destroyed—a genetic equivalent of friendly fire.

There’s also the possibility that the CRISPR/Cas9 plasmid itself could integrate into the genome, again possibly disrupting critical genes. One study showed that DNA injected into mouse muscles persisted for life, cranking out the protein constantly. What would happen if Cas9 continues to be produced in Zayner’s cells for the rest of his life? In the worst-case scenario, it would continue to cut up his DNA indiscriminately. There’s also a study in mice suggesting that DNA injection can accelerate autoimmune responses. Finally, unlike injecting an embryo in which all cells have a high probability of being modified, Zayner’s approach is going to produce mosaic effects. In other words, some cells will be edited, but others will not, which could result in a disfigured arm. Zayner dismisses all of these risks with disquieting nonchalance.

If you don’t want to risk modifying your genome to kill your myostatin gene, you can always buy inflatable muscles to wear under your shirt.

Zayner not only advocates genetic modification of your body, but he also encourages biohacking all of nature. He paints a world where you and your buddies decide to order a pizza one night and, what the hell, genetically engineer a puffin to look like a porg. Eschewing the substantial ethical concerns, he is understating the difficulties surrounding genetic modification of complex animals and the sophisticated equipment and training needed to do it. Below is an excellent TED Talk by Ellen Jorgensen that examines the hyped-up claim that CRISPR/Cas9 is cheap and easy.

There’s no product currently available from The ODIN that could bring on the apocalypse, but it is the principle that concerns many people, scientists and non-scientists alike. Even the most avid science enthusiasts are likely to take issue with providing potential crackpots the tools to screw with the recipe of life. Genetic engineering is exciting and promising, but must be explored with great caution by well-trained professionals following reasonable regulations because there is no way to unscramble this egg.

Biohacking has been banned in several countries, and on November 21, 2017 the FDA updated their web site to state that self-administration of gene therapy is against the law. It seems that Zayner, a self-professed fan of the TV show Survivor, just had his torch snuffed out by government regulators chanting, “The tribe has spoken.”

Contributed by:  Bill Sullivan

Follow Bill on Twitter.

The author thanks Colin Sullivan for research assistance and helpful discussions, and Jason Organ for editing and helpful suggestions.

Why Should You Care How Bacteria Fight Viruses?

Regular readers have been learning a great deal about the human immune system thanks to our ongoing series on allergies by Julia van Rensburg. But did you know that bacteria have an immune system of sorts, too? Yes, even germs get germs!* Bacteria are susceptible to a group of viruses called bacteriophages, or phages for short. Phages resemble early spacecraft and “land” on the surface of bacteria in order to inject their DNA/RNA, much like a syringe ejects its contents.

Houston, we have a problem! A phage has just injected its DNA into our cell!

Bacteria, which have been on Earth for some 3.5 billion years, have had plenty of time to evolve defense mechanisms against predatory phages. Just like human viruses, phages are a most unwelcomed guest. They barge into the cell unannounced, “borrow” cellular components without asking, and then use them to make baby viruses until the cell becomes so engorged with viral progeny that it explodes, releasing the huge viral family so that it can invade more bacteria and repeat the process all over again. Phages that burst the bacterium like this are called “lytic”, but there are other types that don’t blow the house up. These are referred to as “lysogenic” phages and can insert their genetic material into the bacterial genome, becoming a permanent resident of that bacterium. Even more sinister, the incorporated viral genome is copied like all the other bacterial genes when the bacterium divides, so it is inherited by the daughter cell!

Lytic phages will replicate until they blow the infected bacteria apart. In contrast, lysogenic phages can stick around forever, even getting passed on to future generations since the viral genome was inserted into the bacterial genome.

So that sucks – imagine if you had uninvited viral DNA shoved into your DNA – such viruses basically transform you into a GMO. Sorry to inform you, but up to 8% of your genome is already littered with lots of viral DNA. If you oppose GMOs, I hope you can still stand to be in your own skin!

Presently, we don’t know how to remove foreign DNA from our own. But bacteria have figured out a way to get rid of incoming phage DNA, which provides the basis for a type of bacterial immune system.

 

Some combinations work great together, like chocolate and peanut butter. But getting viral DNA stuck into your own DNA, a strategy used by many viruses including HIV, is not a welcome combination.

In 1987, scientists uncovered unusual repeat sequences in the genome of E. coli bacteria, which were later named “clustered regularly interspaced short palindromic repeats”, or CRISPR. In the early 2000s, scientists identified bacterial proteins interacting with CRISPR sequences (now called CRISPR-associated (Cas) proteins) and discovered that they provide resistance to phage infection. Through the efforts of many laboratories, it is now known that bacteria can use a phage invasion as a vaccination by incorporating some of the foreign DNA between CRISPR repeat sequences. This provides the bacteria with a “catalogue” – a memory system, if you will – of foreign DNA that it can pass along to future generations.

But CRISPR is not just a storage system. The bacteria can retrieve these sequences and hook them to Cas9, a nuclease enzyme that can cut DNA. When foreign DNA enters that bacteria, its CRISPR-Cas9 system can specifically target the invasive element and neutralize it.


Foreign DNA, such as that injected by a phage, can be neutralized by CRISPR/Cas9, which serves as a type of bacterial immune system. Bacteria can store foreign DNA sequences in its genome and express them as crRNAs that bind to Cas9. If the bacterium encounters foreign DNA that matches any of the sequences stored in its CRISPR array, the crRNA will deliver Cas9 to that invading sequence to chop it up.

Pretty clever for tiny bacteria, huh? But here is where things get really interesting, or worrisome, depending on your appetite for paranoia. Scientists have adapted CRISPR/Cas9 to work in all sorts of cell types, including human. Cas9 acts as DNA shears that can cut wherever we tell it to by directing it with a “guide RNA” (analogous to how a crRNA operates in bacteria). This provides us with an unprecedented means to easily “edit” the genome of virtually any living thing, including stem cells and embryos. Furthermore, Cas9 has been modified to do more than just cut DNA; versions exist now that can insert new DNA sequences or switch out bad (mutated) DNA with good DNA.

In the hit TV show, Orphan Black, a group of clones discover that their DNA has been “barcoded” to designate them as intellectual property by their maker. Theoretically, CRISPR technology could have been used to tag DNA in this fashion.

The power of genome editing can be used for good. Several diseases, such as cystic fibrosis and sickle-cell anemia, are caused by a single mutation in one gene. CRISPR/Cas9 is a plausible tool that may be able to repair this defect. However, tinkering with one gene can have unforeseen repercussions on other genes, so this exciting technology could have adverse effects. In March, 2015, a group of scientists proposed a ban on editing the human genome, arguing that a greater understanding of how CRISPR/Cas9 works is required before we even consider applying it clinically.

Gene editing using CRISPR/Cas9 can be used to modify the genome of virtually any creature. One recent application is the creation of wheat that is resistant to a fungus that causes mildew.

Here is a video that shows how CRISPR/Cas9 works and some of the applications it may have down the road:

 

 

Contributed by:  Bill Sullivan

Follow Bill on Twitter.

*It should be noted that not all bacteria are “germs”; in fact, many species of bacteria inhabit our bodies to constitute our “microbiome” and provide important services to us. Learn more about your microbiome here.
 

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