The field of medical sciences has evolved exponentially over the years. From advancements in developing new medical drugs to implementing nanotechnology in health monitoring devices, we have come a long way as a species.
One such advancement is the ability to understand and change a human being’s physical and physiological features by altering their genome!
The article provides the reader with an introduction to the field of genetics, goes over the human genome and the applications of gene editing and CRISPR technology.
The Human Genome
Biologically speaking, a human being is a complicated structure having a number of characteristics. These characteristics, like height, hair color, eye color, facial features, and so on, can be determined using their DNA.
Deoxyribonucleic acid (DNA) is a material made up of the fundamental chemical elements (sugar, phosphate, and bases) that carry all the information about how a living thing will look and function.
Biologists and medical professionals decode can decode the information, unique to everyone, by studying the pattern of the DNA.
A gene is a specific part of DNA that codes for one protein. It is the proteins produced by genes that do the work of carrying out the functions of DNA.
The genes work as units of heredity and are responsible for passing on particular characteristics from parents to their offspring.
The total sum of an organism’s genes and genetic material is called its genome. Understanding the human genome has allowed scientists to develop new ways to treat, cure, or even prevent thousands of diseases that afflict humankind.
This is where gene editing comes in.
Genome or gene editing are a group of technologies that allow scientists to alter an organism’s DNA. These technologies make it possible to add, remove or alter genetic material at particular locations in the genome.
Unlike other genetic engineering techniques that randomly insert genetic material into host genomes, these techniques target insertions at highly specific locations.
How does it work?
Gene editing involves enzymes. Enzymes are proteins that enable or speed up chemical processes. The engineered enzymes used in gene editing are called nuclease and they can cut DNA.
Nuclease are engineered with another chemical that guides them to the DNA strands they have to cut. These cut DNA strands can regenerate, but this time they are fed with the desired information to mutate into the desired DNA strands.
New strands, means new genes and new genes mean new characteristics.
Scientists use gene editing to investigate different diseases that affect humans.
They edit the genomes of animals, like mice and fish, and observe how these changes affect their health. They then used their findings to predict how similar changes in human genomes might affect human health.
Furthermore, scientists are developing gene therapy. These treatments involve preventing and treating diseases in humans using gene editing.
A huge breakthrough in gene editing technology is the introduction of Clustered Regularly Interspersed Short Palindromic Repeats (CRISPR).
CRISPR is based on a defense system that occurs naturally in some bacteria. The DNA in such bacteria contains many short palindromic sequences (words that are the same both forward and backward, such as RAAR).
The bacteria would store bits of the viruses they fought off inside these palindromic sequences.
How does it work?
The enzyme used in CRISPR is called Cas9. This enzyme attaches itself to the infected palindromic sequence and cuts the DNA into pieces, retaining information about the virus.
The armed Cas protein would recognize the viral DNA and destroy it immediately in case the bacterium was infected again by the same virus.
Applications of CRISPR
CRISPR has been used in a variety of ways including research, healthcare, pet breeding, food production, green fuel, and much more.
CRISPR systems are being implemented in studies related to alleviating genetic disorders in animals and are likely to be employed soon in the clinic to treat human diseases of the eye and blood.
China and the United States have approved two clinical trials using CRISPR-Cas9 for targeted cancer therapies.
Beyond biomedical applications, these tools are now being used in studies to speed up crop and livestock breeding, engineer new antimicrobials, and control disease-carrying insects with gene drives.
Scientists have been able to develop methods to destroy antibiotic-resistant bacteria by modifying the genomes of bacteria-killing viruses (bacteriophages) with CRISPR-Cas9 technology.
These systems also enable the creation of animal models for human disease and the removal of HIV from infected cells.
In a mouse model of human disease, CRISPR corrected a genetic error, resulting in the clinical rescue of diseased mice.
3. Pet Breeding
CRISPR has been applied to early embryos to create genetically modified organisms, and has been injected into laboratory animals to achieve substantial gene editing in their tissues.
Approaches based on CRISPR have been used to modify the genomes of animals including mice, rats, and other non-human primates. These approaches could be employed to enhance productivity, disease resistance, and activate sought traits/features in pets.
Using CRISPR, we may even be able to introduce a generation of novel animal models.
4. Food Production
CRISPR gene editing technology can improve crop yields and quality; plant drought resistance, herbicide and insecticide resistance, increasing food safety and security.
It can also help the removal of antibiotic resistance, improve product shelf life, and accelerate the process of plant domestication.
Better quality plants mean better quality fodder for animals, thus boosting their health. Since plants and animals form the basis of our food chain, we can have better food quality and products.
5. Green Fuel
Green fuel is fuel that is produced from organic sources and is environmentally friendly.
CRISPR has made it possible to produce double the amount of biodiesel (a form of green fuel) from phototropic algae.
This fuel is obtained by doubling lipid production in algae, using CRISPR to tweak genes. Lipids are combustible and essentially make up biodiesel.
But is gene editing ethical?
Altering the natural course of action is sure to invite ethical concerns. Alter human genetics using gene editing technologies, such as CRISPR, have not found unequivocal support. This is because changes made in the genes of egg and sperm cells could be passed on to future generations.
There is a huge debate on whether this technology should be used to enhance normal human traits (such as intelligence or height).
Safety concerns also arise while using this technology as there is always the possibility of having off-target effects (edits in the wrong place) and mosaicism (when some cells carry the edit but others do not).
Based on concerns about ethics and safety, genome editing of reproductive cells is currently illegal in many countries.
Understanding the human genome has allowed us to revolutionize healthcare technology on a nanoscale.
Gene editing and CRISPR technology that have provided groundbreaking applications in terms of eradicating disease and even correcting human imperfections.
Scientists predict that these technologies are the key to creating a disease-free generation of homo sapiens with perfect characteristics.
What are your views on gene editing? Let us know in the comments.