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Gene editing has been a controversial science for a long time, but the pace of its progress might actually be too fast for the controversy to keep up.At this rate, it won't be long before geneticists edit not only DNA but also when and how genes encoded by that DNA are expressed according to a new paper published in the well-known biology journal, Cell.The study was conducted by researchers at the Salk Institute, and it reports their use of CRISPR, the controversial gene-editing tool, to mitigate Duchenne muscular dystrophy and type 1 diabetes symptoms in mice without actually cutting the genome itself.

The study doesn't use CRISPR-Cas9 to make cuts to the genome but, rather, uses the nanotech tool to deactivate genes.The team convinced liver cells to produce insulin-like pancreatic cells as a means to treat type 1 diabetes.Duchenne muscular dystrophy causes muscle deterioration, so the team used CRISPR to activate genes that code for a protein called follistatin.Follistatin codes muscles, so this gave them a seemingly unprecedented level of control for treatment of muscular dystrophy.

This is significant because gene editing as a means of treatment leads people to question the ethics of altering DNA.In particular, the age-old, ethical gray area is and has long been whether or not it's right or wrong to permanently change a person's DNA.The edits used in this study are impermanent and can be toggled back and forth.CRISPR is usually used to cut both strands of DNA, and many scientists have had reservations about doing this because it bears a risk of unwanted mutations that cannot be anticipated.

This study illustrates that geneticists are now capable of circumventing the controversy of irreparably damaging or changing one's DNA.Rather than making physical cuts on the human genome at all, they can now use that same controversial tool to simply toggle phenotypic expression on and off.Epigenetics holds the potential to treat a vast number of diseases if it isn't ramparted by the ethical conflict that comes from editing genetic material at the risk of spawning mutations elsewhere on the genome.A more narrow but still large number of diseases can be treated via the methods exemplified in the new study — those diseases not caused by genetic mutations.

The controversy still applies to many other diseases, however, even if every epigenetics lab on the planet stopped cutting genomes immediately and only focused on toggling gene expression.Moreover, the ethical dilemma stems from deeper than just the risk of mutation.Dr.Calum MacKellar, the Scottish Council on Human Bioethics's director of research, addressed this last month (prior to the publication of this new study) in a BioNews article reflecting on the international conference of the Council of Europe Committee on Bioethics in Strasbourg, France.

The delegates at the Relevance and Challenges conference talked about the prohibition of intentional germline procedures, which was outlined in the convention's Article 13.Article 13 reads: "An intervention seeking to modify the human genome may only be undertaken for preventive, diagnostic or therapeutic purposes and only if its aim is not to introduce any modification in the genome of any descendants." Paragraph 91 of the convention's Explanatory Report expounded on this saying, "Interventions seeking to introduce any modification in the genome of any descendants are prohibited.Consequently, in particular, genetic modifications of spermatozoa or ova for fertilization are not allowed."

MacKellar says that the recurring question at the event was how fundamental equality of the value of every human being's individuality can remain protected if Article 13 is removed or amended, yet no real answer ever came.On that note, MacKellar says, "This was unfortunate because the selection of future human beings, based on their possible quality of life, is at the very core of germline procedures.For example, when a one-cell embryo, or sperm and egg cells before they are used in conception, are edited, a new individual who would not otherwise have existed is being brought into being.

"Indeed, any change, no matter how small, to the variables in the creation of an individual results in a very different person coming into existence.(3) In other words, with most germline procedures one is not treating someone who exists, but making sure only certain persons, and not others, are brought into existence." The opposing argument challenges whether or not this qualifies as actual discrimination if there is (a) no consistent pattern of types of persons being disallowed to live or (b) no individual who can perceive being discriminated against.

This is one of the many "where to draw the line" questions that were asked back in 2015 when Chinese scientists published a study in which they altered non-viable human early embryos.Dutch researcher Jeantine Lunshof is an assistant professor at the University Medical Center Groningen as well as a researcher at Harvard Medical School.She writes for The Washington Post, "while the deliberation and decision-making on stopping rules will be political in the broadest sense of the word, it is the work at the bench that confronts us with new realities in biology.

"For example," Lunshof adds, "what if we see the spontaneous development of structures typical of early embryos in a group of cells that has nothing to do with embryos?"

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