Gene editing and its ethical concerns

Gene editing is a type of genetic engineering which has the potential to treat over 10,000 diseases. Gene editing is a way to make very specific changes to DNA. This is done by using enzymes that have been designed to make targeted modifications to specific genes by either inserting, deleting or alternating the base sequence of DNA.

Gene editing can potentially treat genetic disorders, by cutting the DNA at the targeted site and letting the cell’s natural DNA repair mechanism kick in to delete the mutation or insert the correct allele. Theoretically, this method  provides a treatment for genetic disorder, however, it is still in the early stages of development.

The idea of using gene editing to treat diseases began during the 1950’s, where scientist discovered that genes are passed on from parent to offspring, and that changes in the sequence of DNA can cause issues. A few years later, they realized that these ‘molecular mistakes can cause genetic disorders. This was the fundamental idea behind gene therapy. Technology development for gene therapy proved to be extremely difficult. At the start, researchers and scientists focused on trying to minimize consequences by providing a functional copy of the mutated gene instead of fixing the mistakes in the DNA. Scientists then realized, that in order to correct these genetic mistakes, they needed to find a way to break the DNA at specific locations.

Scientists discovered 2 ways to break the DNA at precise locations. One of which was zinc finger nucleases (ZFN). This particular method uses 2 things. The first one being fusion proteins, which are  composed of DNA binding domains that recognize and bind to the specific DNA sequence. The second thing being nucleus domain, these act like scissors and cut the DNA. Combining the fusion proteins and nucleus domain together would create proteins that can accurately target and edits parts of the genome. The other method is called ‘Transcriptions activator-like effector nucleases’ (TALENs). This method consists of proteins from plant bacteria called transpiration activator-like effectors that bind to specific DNA sequences. TALENs also have a nucleus domain which cuts the DNA. These are used as alternatives to ZFNs. However, these methods aren’t what are used now.

In 2012  scientists Jennifer Doudna, and Emmanuelle Charpentier, discovered a new method for gene editing called CRISPR-Cas9. ‘CRISPR’ stands for clustered regular interspaced short palindromic repeats, which are parts of DNA found in several different microorganisms. The ‘Cas9’ is an enzyme which is guided by gRNA to specific locations in the genome, and then cuts the DNA. This allows the cells natural repair mechanisms to make changes to the genetic code. The CRISPR-Cas9 method proved to be much more efficient than ZFN and TALENs. Even though gene editing is still in its early stages of developments, it has potential to treat diseases in the future.

However, there are numerous ethical implications that come with it. For one, safety, there is a possibility of off target effects, which occur when Cas9 acts on untargeted genomic sites, this can lead to unexpected consequences. Another ethical problem with gene editing, is it raises the question of ‘Are we playing the creator?’ many people think that we shouldn’t try to change the base sequence of DNA just because we can. Furthermore, if Changes to the DNA are made in reproductive cells, this can be passed on to future generations, which raises ethical questions and concerns on the long-term implications of heritable genetic modifications and unintended consequences. Lastly, gene editing raises concerns that if this type of genetic engineering becomes available to the public only the rich will be able to afford such treatments. It also raises ethical questions on using gene editing for human enhancements.

Gene editing is very controversial, with many people supporting the idea, and many against it. Since it raises many ethical concerns, there is a need for the regulatory authorities to oversee the development and advancements made in gene editing technologies. The regulatory authorities ensure that the technologies and methods used are not only ethical but also safe, efficient, and have minimal risks.