This new tool that represents the state-of-the-art technology in gene editing came as the latest improvement on existing zinc fingers and TALEN’s technologies, enabling fast and relatively easy-to-use genome modifying system.
CRISP uses bits of RNA, which is rather easy to synthesize, compared with previous time-consuming technologies based on the use of large proteins, to “find and cut a desired DNA sequence” in order to make the modifications to the DNA.
CRISP clusters of DNA were first observed in bacteria in 1980s, but it was not until recently that scientists realized this is a part of their defense system against viruses. To protect themselves, bacteria incorporate “sequences of viral DNA into their own genetic material” and use it in any subsequent virus attack to produce RNA that searches these viral DNA sequences and deploy proteins to cut them up.
Based on these findings, scientists Emanuelle Charpentier and Jennifer Doudna used Cas9 enzyme, a combination of a single RNA and a cutting protein to slice and replace a desired DNA sequence in test tubes. A year later Yi Zhang and George Church reported these findings could also be used on animals and humans. CRISPR technology is now so potent that it allows alterations to be made on a level of a single DNA letter.
In another MIT Tech Review, named Engineering the Perfect Baby, Antonio Regalado investigates the possibility to apply the CRISPR-Cas9 technology to alter and improve human genome.
Scientists agree that human genetic code is far from being perfect. That’s why we have so many genetic diseases, such as different types of cancer, Parkinson’s, and Spinal Muscular Atrophy, or a propensity for some equally terrible conditions.
Relative to the environment, some genetic mutations are good and some are bad. Some might have played an important role at a certain point in our evolution, but now are either completely useless or potentially dangerous for us.
Geneticists such as James D. Watson, Nobel Prize winner in Physiology or Medicine, one of two scientists responsible for the identification of the molecular structure of our DNA’s, which marked the era of biological revolution, and George M. Church, Professor at Harvard and MIT, and a celebrity in the world of genetics and synthetic biology, think we should not shrink back from using available biotechnology to repair nature’s mistakes and obsolescences.
Potentially, gene editing might also help us fight some really bad viruses, like HIV, or prevent the effects of aging. In adult humans any gene therapy of this sort would not affect future generations, while if applied to germ cells, it could result in germ-line engineering and the creation of augmented humans. As Jenifer Doudna told Antonio Regalado,” Any scientists with molecular biology skills and knowledge of how to work with [embryos] is going to be able to do this [edit human embryo using CRISPR].”Such practices are currently banned in many countries, but the research of the concept is still very much alive. Once the researchers demonstrate the possibility to produce offspring free of genes responsible for inherited diseases, how would society react? And what if we want to go beyond the point of simply repairing the genetic material, towards further enhancements of human traits that would produce perfect humans?
The American Medical Association’s official position is that germ-line editing should not be done “at this time” since it “affects the welfare of future generations”. On the other hand, should it be tested on adults who volunteer for the research?
Biotech research is so diffused nowadays that no single authority can monitor and dictate its development. Therefore, with the available technology, it is just a matter of time before germ-line engineering is attempted somewhere in the world. It seems that we are at the point where the question is rather – how it should be done (what should be the initial guidelines), and not could and should it be done at all.