Does our future hold designer babies?
Ruhani Nagda, Class 11

The smallest unit of the human body is the cell. The cell is incredibly complex in its design, but what stands out the most in it is the nucleus. The nucleus contains thread-like structures called chromosomes. Chromosomes are incredibly unique, because while they might be microscopic they contain a molecule, DNA, that is so long that if all the body’s DNA was uncoiled, it would be the same length as the Earth to the Sun about 300 times.

What is DNA?
DNA is a molecule that has 2 chains coiled together to form a double helix shape, as pictured here. It acts as a code or evolutionary instructions for our body. This code is made up of 4 bases or 4 letters - A (Adenine), T (Thymine), C (Cytosine), and G (Guanine). Combinations of these 4 bases or letters make up genes that code for the different functions of our body, down to our appearance and characteristics. Each person’s code is unique, which is why we all look and act so differently.

Why is it important?
Sometimes, our DNA can be faulty, broken in some ends or existing in a mutated form with the incorrect bases in place. As a result, some people develop rare genetic disorders like cystic fibrosis, where the lungs fill up with fluid, preventing breathing, or Down Syndrome, where people born with it have flattened faces and reduced muscle tone (see Box).

BOX Down Syndrome
Down syndrome is a genetic condition where people are born with an extra chromosome. Most people have 23 pairs of chromosomes within each cell in their body, for a total of 46. A person diagnosed with Down syndrome has an extra copy of chromosome 21, which means their cells contain 47 total chromosomes instead of 46. This changes the way their brain and body develop.
A child with Down syndrome may have intellectual or developmental disabilities, such as with how they walk and move (gross and fine motor skills), speak (language development skills), learn (cognitive skills) or Play (social and emotional skills). The child could show behavioural difficulties like stubbornness and throwing tantrums. It may have difficulty paying attention and exhibit obsessive or compulsive behaviors.
END OF BOX

CRISPR
These genetic disorders oftentimes don’t have a cure, and people who are born with it have reduced life spans and live lives full of struggle and pain. For many years, scientists tried incredibly hard to find cures or at least medicines to control the symptoms of such diseases. That brings us to CRISPR technology.
CRISPR-cas 9 is a gene-editing tool that allows scientists to look at people’s genes and edit them to fix any problems like broken ends or mutated DNA. So how does it do this? CRISPR stands for Clustered Repeated Interspaced Short Palindromic Repeats, which sounds incredibly confusing, right? In simpler words, CRISPR is a system that exists, usually in bacteria, which allows them to use a CAS9 protein to cut off unwanted DNA with surgical precision.
This CRISPR system is programmable, so scientists can use it to cut off any piece of DNA they want, turn off malfunctioning genes and study DNA. All they have to do is add a copy of the DNA they want to modify into the system and insert the system into a living cell. Then the CRISPR system handles the rest.
So how does it help people with genetic disorders? Well, CRISPR can be used to cut off the mutated DNA and to turn off genes that cause the genetic disorders, hence curing the patient. The picture shows the CRISPR/Cas9 gene editing complex from Streptococcus pyogenes. The Cas9 nuclease protein uses a guide RNA sequence to cut DNA at a complementary site. Cas9 protein is seen in red, DNA is yellow, and RNA blue. Of course, once you can delete a gene, you can insert one as well. The schematic shows how CRISPR works for both cases. The starting point in both cases is to cut the DNA at the correct place.
Humans start out as embryos in the bellies of our moms. Due to advances in CRISPR technology, scientists can now also edit the genes of these embryos. This means that scientists can now check these embryos for faulty genes and cure them before the birth of the child. Once these genetic defects are cured, the child will also now be unable to pass them down to his or her children in the future. This means that scientists can make permanent changes to the genes of the child before it is even born.
While like highlighted before, this can be a good thing, it can also be potentially disastrous. If parents of the child can have its genes edited to remove potential genetic disorders, can they also not alter its genes to change its appearance, perhaps? For example, if they wanted a child with blue eyes, but their child had brown eyes, could they not possibly edit that and change it to blue eyes. This can be a slippery slope, leading to a world full of modified “perfect” humans, where we vainly use gene editing to polish our own egos.
So in conclusion, we can see that gene editing tools like CRISPR are going to be able to save millions of lives and probably save many young children from a life of pain. But if we aren’t careful in its use, we could always end up in a world full of “perfect” humans without a single flaw, changing our bodies constantly to fit the current trends. What do you think of CRISPR? Do you think we should continue to develop this technology?
Sources: https://www.vox.com/, Wikipedia