I recently began reading more about gene drives, particularly their real-world implementation, after stumbling upon an article in the New York Times. It talked about research with genetically modified gene drive mosquitoes in Principe and São Tomé in the Gulf of Guinea, and explained that it was hard to get funds to back the research and its implementation to attempt to save lives. The comments on the site seemed to vary, with some seemingly ready to challenge the science behind the cause since so many deaths occur yearly due to malaria, while others asked for the real need for a technology when basic healthcare and medicines could also be used. There were also some comments scorning the reference made to Jurassic Park, and truly, comparing a gene technology being used to treat a disease that has been taking the lives and opportunities of the both young and old, seems a bit far fetched. It is just the lack of the real-life information and reassurance needed to determine whether there would be any side-effects to introducing an organism into the world with this new potentially game-changing technology. But this information is impossible to get without, you know, actually introducing the organism into the world. And if anything, this new technique is actually more advanced than just the basic gene editing known for quite some time now, and guarantees dramatically faster results, which would save millions of lives.

What most people see on labels like “non-GMO” in supermarkets refers to plants or animals that have been modified to produce more “convenient” foods. For example, seedless fruits, a longer shelf life, or the introduction of vitamins like beta carotene into rice, have all been modified to help people with deficiencies like yellow rice. These technologies are used to solve even more major challenges: a fairly new research is being conducted in universities in the UAE to genetically engineer qualities in plants like being able to grow in salty water to combat food security issues. The principle uses DNA cutting techniques derived from bacteria, called CRISPR with its little sidekick Cas-9 (called a CRISPR associated protein) as a complex, which cuts DNA at specific sequences.

There is a little guide molecule attached to the protein complex that is complementary to the gene you want to cut, and that lets the proteins know where to cut DNA. This guide molecule can be changed according to the gene (sequence of DNA) that you want to cut out. This would also be used to cut the spot where the new gene will be inserted in the organism we plan to modify. After that, specific proteins glue the gene by bonding it (at the molecular level) to the right section of the DNA of the to-be modified organism, along with its toolkit to let this new DNA have an impact on the organism. This has a definite effect on the organism, but it only gets carried on to the next generation at a rate of about 50%. The way scientists tell apart which have been modified is by attaching a marker (usually a fluorescing gene) along with the gene in the organism, called a marker gene. From there, it is very clear that the other inserted protein, for whatever function it may be, is also present. This is important for when someone would want to check for genes that do not have the most visible effects.

With this background in mind, we can come back to the malaria problem, which is one of the most common dilemmas where gene drive implementation is discussed. GM-mosquitoes and other bugs have been introduced in multiple parts of the world, and they are not the only bugs whose DNA has been modified to help humans deal with vector borne infections (diseases that spread through means of an organism, usually a small insect that the disease causing pathogen can live inside of). What sets the newer technique to modify them apart, is that they do not only use CRISPR to modify the DNA (that codes for the feature you want expressed, e.g. bigger fruit), but also insert the CRISPR units that would help the modification take place by itself in future organisms. This leads to the gene being modified with crazy high certainty in most future organisms. Especially for mosquitoes, who on average lay 100-200 eggs per clutch, the concept of gene drives would make the process exponentially efficient.

However, there are two approaches researchers took. The first approach makes female mosquitoes sterile and hence reduces not only disease but also the population of mosquitoes. The other adds a gene that stops them from spreading malaria, which in relativity to the first one, is less potentially threatening to ecosystems. Then again, to implement either project there needs to be much more testing, risk assessment, as well as governing body approvals in the areas where implementation is to be carried out. Just to add further context, gene drives do sometimes occur naturally, and there is some research on a gene drive that stops a species or rice from reproducing with other species to form hybrids, by making male offspring sterile. This can lead us to think that gene drives are actually a natural phenomenon and might not impact ecosystems that much.

Studying gene drives, both synthetic and natural, have given scientists better insight into their properties, however there is still much caution regarding their use as for now, especially due to the uncertainty surrounding this new technology.