It’s the most exciting time in genetics since the discovery of DNA in 1953. This is mainly due to scientific breakthroughs, including the ability to alter DNA through a process called gene editing.
The potential of this technology is astonishing – from treating genetic diseases, modifying food crops, to resisting pesticides or changes in our climate, or even to “bring back to life” the dodo, as one company claims to be. want to do.
We will only hear more about gene editing in the future. So if you want to make sure you understand new updates, you first need to understand what gene editing actually is.
Our DNA is made of four key molecules called bases (A, T, C, and G). Sequences of these four bases are grouped into genes. These genes act as the “code” for important substances the body is supposed to make, such as proteins. Proteins are important molecules, vital for maintaining a healthy and functional human being.
Genes can be short, usually made of less than a hundred bases. A good example is ribosomal genes, which code for various ribosomes, molecules that help make new proteins.
Long genes are made up of millions of bases. For example, the DMD gene codes for a protein called dystrophin, which supports the structure and strength of muscle cells. DMD has over 2.2 million bases.
How does gene editing work?
Gene editing is a technology that can alter DNA sequences at one or more points along the strand. Scientists can delete or change a single base or insert a new gene. Gene editing can literally rewrite DNA.
There are several ways to edit genes, but the most popular technique uses a technology called CRISPR-Cas9, first documented in a seminal paper published in 2012. Cas9 is an enzyme that works like scissors that can cut DNA.
It is assisted by a strand of RNA (a molecule similar to DNA, in this case made by the scientist), which directs the Cas9 enzyme to the part of DNA the scientist wants to change and binds it to the target gene.
Depending on what the scientist wants to achieve, they can simply remove a segment of DNA, introduce a single base change (for example, change an A to a G), or insert a larger sequence (such as a new gene). Once the scientist is done, the natural DNA repair processes take over and glue the cuts back together.
What could gene editing do?
The benefits of gene editing for humanity can be significant. For example, making a single base change in people’s DNA could be a future treatment for sickle cell disease, a genetic blood disorder. People with this disease have only one base that has mutated (from A to T). This makes the gene easier to edit compared to more complex genetic conditions such as heart disease or schizophrenia.
Scientists are also developing new techniques to insert larger segments of bases into crop DNA in hopes they can create drought-resistant crops and help us adapt to climate change.
Why is gene editing controversial?
Gene editing is a controversial topic. Unless governments work with scientists to regulate its use, it could become another technology that only benefits the richest people.
And it comes with risks.
The first case of illegal implantation of a genetically modified embryo was reported in China in 2019 and led to the imprisonment of three scientists. The scientists had been trying to protect twin fetuses from HIV transmission from their father.
But when other scientists read passages from an unpublished paper written by the DNA experiment leader about the twins, they feared that instead of introducing immunity, the researchers were likely creating mutations whose consequences are still unknown.
The risks of developing designer babies are so great that it is unlikely to become legal anytime soon. A small mistake can destroy a baby’s health or lead to other diseases throughout his life, such as an increased risk of cancer.
The laws and regulations surrounding this technology are strict. Most countries prohibit the implantation of a human embryo that has been genetically modified in any way. However, as the 2019 example shows, laws can be broken.
Gene editing has its advantages. It has the potential to cure genetic diseases and create drought-resistant crops. But scientists must work closely with lawmakers and policymakers to ensure the technology can be used to benefit humanity while minimizing risks.
The fact that a private company recently announced plans to try to bring back the dodo shows the importance of international gene editing laws keeping pace with corporate ambitions.
This article is republished from The Conversation under a Creative Commons license. Read the original article.
Gavin Bowen-Metcalf does not work for, consult with, own stock in, or receive funding from any company or organization that could benefit from this article, and has not disclosed any relevant connections outside of their academic tenure.