The world would be a monotonous recycled old newspaper if it were not for the unique flaws and beauties that make each one of us special. Just like how our exceptional characteristics make all of us different from the rest, our unique biological makeup makes each of us one of a kind. One aspect of the study of this uniqueness is genetics.
What is genetics?
Genetics is the study of heredity and the expression of traits and how they are passed from generation to generation.
Genetic information is stored in each cell’s tiny individual brain; the nucleus, engraved in structures called chromosomes, in the form of DNA, or deoxyribonucleic acid. DNA, being a complex molecule that guides the growth, development, function, and reproduction of all living things, is the mere blueprint of life. Genes are building block-like segments of this DNA, containing chemical compounds that provide the coding for all information about a person’s inherited traits.
The ancient tale of genetics
For 2000 years, the concept people were working with came from Aristotle, who suggested that all of us are a mixture of our parents’ traits, with the father supplying the life force and the mother supplying the building blocks to put it all together. However, the idea of us being grey individuals resulting from the black and white mixing of our parents was not the most accurate explanation.
An Austrian monk, in the name of Gregory Mendel, was the first to start thinking about the passage of characteristics from one generation to another. In the mid-1800s, Mendel spent time running around with garden pea plants, with the hope of finding answers to his curiosities about heredity.
He grew and tracked 28,000 plants, cross-bred different strands of garden pea plants, and observed their progeny for seven traits. After seven strong-willed years of studying pea plants, Mendel noticed that some characteristics seemed to be passed down often, and some tended to disappear after a generation. In his findings, he noted the role of “factors” that influence the expression of traits. These factors were later coined as “genes.” As Mendel came up with Mendelian laws that changed the view of genetics forever, he was recognized as the father of genetics.
The tale continues…
There are around 20–25,000 genes in the human body, and this collection of genes, called the “genome,” is what determines a person’s traits by influencing factors on a cellular level. It is the code that runs the program of humanity.
The year 1900 marked the “rediscovery of Mendel” by Hugo de Vries, Erich von Tschermark, and Carl Correns, and by the year 1915, the Mendelian principles of genetics were being studied in a wide variety of organisms.
One of these organisms studied was the Drosophila melanogaster; the fruit fly, studied by Thomas Hunt Morgan, developed the Mendelian model in 1925, which was widely accepted.
A modern twist on the helix
By the 1940s and early 1950s, experiments revealed DNA to be a part of a chromosome that held genes. Along with the grand discovery of the DNA double helix by Watson and Creek in 1953, the destiny of science changed forever, marking the transition to the era of molecular genetics.
In the following years, chemists, biologists, and geneticists worked out the relationship between nucleic acids and proteins and discovered the genetic code.
An international effort to decode the human genome was launched at the turn of the 21st century. This game-changer was called the “Human Genome Project”, and it successfully identified about 99% of the entire human genetic sequence. Discoveries in genetics have unearthed tremendous opportunities in medicine, such as genetic testing and the manipulation of genes.
Re-writing the destiny of life
Humans have been creating, recreating, and editing life for thousands of years for their benefit. Through selective breeding, we strengthen beneficial traits in plants and animals, without even a single clue of the real science behind them.
In the 1990s, there was an experiment in human genetic engineering in which babies were created to carry genetic information from three humans to treat maternal infertility, making them the first humans to have three genetic parents.
The magic of genetic engineering has turned some parts of our ordinary world into Hogwarts, giving rise to numerous genetically modified organisms, such as fast-growing salmon, glow-in-the-dark zebrafish, super muscled pigs, featherless chickens, and transparent frogs.
Unfortunately, all this magic came with a price tag. Gene editing was extremely expensive, complicated, and time-consuming. However, with a revolutionary novel technology called CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats), the tables have been turned forever, by shrinking the cost of genetic engineering by 99% overnight. CRISPR has allowed scientists to do year-long experiments within a few weeks, saving a huge amount of time and money.
The revolution began when scientists learned that the CRISPR system is programmable, meaning you can feed in the copy of the DNA you intend to modify and then introduce the system into a living cell. If the old traditional genetic techniques were paper maps, CRISPR was a GPS system.
With a powerful tool like CRISPR, we might be able to fight off deadly genetic diseases, dangerous viruses, and even fatal cancer. Modified humans could alter the genome of our entire human species because their engineered traits are passed on through generations, slowly modifying the whole gene pool of humanity. The discoveries of genetics continue to prove to be one of the greatest human achievements during the timeline of mankind.
As scary and nerve-racking as it sounds to redefine the definition of humanity and its existence, the continuously evolving discoveries of genetics are changing life forever, turning our bedtime science fiction into science reality.
A reality, full of opportunities that will re-wire the unwritten history of our future.
By Rtr. Ama Upeka Perera