How The Gene Be Modified Inside a Living Body?

Gene Modification cover

DNA as most would be familiar with is the building block of the human body. Throughout our lives, our cells are constantly dividing and replicating, and during this essential information is conveyed to the new cell, which knows exactly how to perform its task, they have its own system that allows them to follow a certain pathway, each individual has their own unique sets of DNA that contain their genetic code. But as of today genes are being modified in the labs, how and why such modifications are happening?

What are Genes?

As DNA is the most important information building block and command center that gives the order to the cells on what information to store and how to process it. These double helix structures are tiny and consist of four components adenine(A), guanine(G), cytosine(C), and thymine(T). These four alphabets are what write the entire scriptures upon scriptures of our genetic code. As for the genes, a specific segment of a chain of DNA is known as Gene, this particular segment contains very specific information that makes us who we are and which cannot be decoded easily, as even to write information stored in one gene, hundreds of thick notebooks would be required, and the entirety of DNA chains if laid in a linear fashion are so vast that they can encircle the Earth 2.5 million times.

Gene chain

A representation of a gene.

Gene Modification

Gene Modification simply means the direct manipulation or alteration of the genetic makeup of an organism using various molecular techniques. Another term for this process is known as Gene Editing, and there are basically two types of it.

  • Somatic Gene Modification: In this genes of some cells are added to, cut up, or are changed in an existing person. These are usually done to get rid of some medical conditions, however, these are only done for very selective disorders and the cost is extremely high (or used to be as it’s explained below).
  • Germline Gene Modification: When genes of an egg, sperm, or early embryos are altered to have specific traits it is known as Germline gene modification, one can even say it is solely for reproducing the “perfect baby”. However, it is banned in about 40 countries seeing the risk it carries, others also fear that if allowed it would become a marketplace for specific genes.

The Gene modification process might sound like the stuff of the future, however, we humans have been doing it for years now. Selective breeding is also a type of gene editing which have been occurring since ancient times and domesticated animals like dogs and specific species of cows are the best examples of it. According to scientists, we started taming wolves around 40,000 years ago and around 32,000 years ago selective breeding was initiated to produce dogs with very selective features that would aid in various tasks. But another example of gene editing dates back even further and we are still doing it to this day.

Bull terrier selective breeding

A difference between Bull terriers after years of selective breeding.

As you can imagine all the crops that we consume today, at one point were wild and would’ve been very different from what we eat today. As early as 9000 B.C. the records of selective breeding of wheat crop with other plants have been found. Scientists believe this was done to yield more crops and to produce a larger grain. Other crops like corn have also been heavily altered. Apart from crops which may or may not appear that drastic in change, fruits like bananas have surely changed over the years. It is quite surprising to know that bananas prior to gene editing used to have large seeds in them and were quite short in size. A fun fact about bananas is that the species of banana that our elders used to consume was completely wiped out due to a virus but thanks to gene editing we were able to produce similar tasting bananas, but still, it is a different species.

Banana GMO

Difference between wild and GMO bananas.

Altering Genes in a living body

In the past gene engineering was an extremely expensive process, also it used to take years to make a few alterations. But thanks to something known as CRISPR, the cost of gene editing has come down significantly and now it only takes a few weeks to carry it out. In order to understand it, we must know about the battle that is continually been going on for ages. Viruses are constantly attacking and invading living organisms and their goal is to survive and grow their population. They do this by injected their copy of DNA into the bacteria of an organism, unfortunately, bacteria are not capable enough to fight against this new invader DNA and they fail to prevent it and ultimately dies. But, if that bacteria survives they launch a true anti-virus system, as it stores this specific DNA and combines it on its own and when the same virus attacks the bacteria releases RNA that kills off these viruses right away. The specific protein is known as CAS9 is responsible for it, it is so precise in its job that it will find a 100% match of the attacking virus and cut it completely rendering it useless. Scientists found that not only it is precise it is also programmable.


The process of CRISPR with CAS9.

Just by providing a copy of DNA to CAS9 and injecting it into a living cell, it is capable of altering and editing living cells to switch certain features on and off and it also allows to study of various effects on DNA sequences. Additionally, it works for every kind of cell, meaning it works on microorganisms, plants, animals, and humans. In a study, HIV-positive mice were used where about 99% of their cells had HIV, and later upon experimenting with the CAS9 protein, the new cells were injected into the tails of the rats and up to 50% of the cells were cured. In theory, this can allow us to cure dangerous diseases like cancer with ease and trials are already underway to treat them.

Ultimately, it comes down to the medical teams, government, and the consensus of the general public if they allow it. As with each and every new discovery speculations and doubts are bound to happen, maybe in the future, we will all rely solely on genetic engineering.

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