Here is the second part, the flip side, of CRISPR. In a previous article, we reviewed the revolutionary changes CRISPR brought for us, but know its time to unveil the darkness that it holds. From accidental generational mistakes to the purposeful disregard of general ethics, CRISPR isn’t a very hard topic to find material to write about, but definitely an eye-opening subject to read on.
Though not many people have heard of it, CRISPR is quite a big deal in the science world. For something that has the power to turn our world into a messed up dystopian anarchy, it isn’t too popular. In its essence, CRISPR is just a method of fast, cheap, accurate gene-editing. Definitely not scary. In a previous MedAI article (check it out!) we went over how exactly CRISPR is a lifesaver, quite literally, for the whole world. But as to any good thing, we must consider the flip side.
Now as a brief overview, CRISPR works primarily as a kind of a database in bacteria. Whenever a specific virus passes through the bacterial cell the CRISPR immune system stores that information as a block in its “library”. That information is then used to cut a crRNA that matches perfectly to the genome of that virus. Using the ACE9 protein the crRNA binds to the genome and cleaves it upon impact. This method is replicated whenever that virus or a new one enters. So in one sentence, it is pretty much the solution to any disease. And due to this fact, many companies and scientists have gone down that exact path. By taking this mechanism out of bacteria and replicating parts of it inside the human body, scientists found that they can very easily just remove the infected area of DNA and replace it with a healthy piece. But scientists and companies with the wrong intentions can also very easily accomplish other things.
He Jiankui, a Chinese researcher, claimed that he had edited the genes of two human embryos and that they had been brought to term. In gene-editing there are two branches that you could go down: somatic or germline.
The germline editing He claimed to have carried out is enormously different from the somatic editing revolutionizing medicine. Somatic gene therapies involve modifying a patient’s DNA to treat or cure a disease caused by a genetic mutation. In one clinical trial, for example, scientists take blood stem cells from a patient, use CRISPR techniques to correct the genetic mutation causing them to produce defective blood cells, then infuse the “corrected” cells back into the patient, where they produce healthy hemoglobin. The treatment changes the patient’s blood cells, but not his or her sperm or eggs. Germline editing, on the other hand, alters the genome of a human embryo at its earliest stages. This may affect every cell, which means it has an impact not only on the person who may result, but possibly on his or her descendants. The very risky procedure of germline-editing can very evidently cause a domino effect of genomic problems getting bigger and bigger. This “mistake” will not stop with that patient but will get passed on for generations.
Komentáre