What makes a rose red rather than pink? A dog’s tail short rather than long? A person’s eyes brown rather than blue? All these factors (and many more) are decided by genetics. Every organism is made of cells, and it is inside these cells that the genetic material lives.
In the 1850s and ‘60s, Gregor Mendel used pea plants to track traits like plant height, pod shape and color, seed shape and color and flower position and color. He tracked changes from generation to generation. By doing this, Mendel noticed that certain traits were dominant and others were recessive. Mendel is now considered the founder of the science of genetics.
The study of genetics has come a long way since then. Scientists have figured out how to genetically modify plants, not just track traits. In 1983, a farmer inserted an antibiotic-resistant gene into a tobacco plant. This was the beginning of genetically engineered plants. Now, it is common to do this, so crops become resistant to certain pests and diseases. Some plants can be
modified in other ways, too. In China, researchers have figured out a way to genetically modify rice. By inserting nutrients into the developing seed, they’ve produced rice that could potentially decrease the risk of certain cancers as well as heart disease and other illnesses.
Scientists are applying this knowledge to human genetics, too. With a flake of skin, a drop of blood, a piece of hair or a sample of saliva, they can explain why someone has physical traits, see if they are vulnerable to certain illnesses and see where their ancestors originated! Someday, we may be able to use genetics to help keep people healthier so they can live longer lives.
While genetic engineering is a relatively new science, farmers have been using genetics for tens of thousands of years. Breeding plants and animals to bring out desired traits is nothing new. That’s how people domesticated animals. There is evidence dating back to 9000 BCE that suggests this is when people domesticated sheep, cows, pigs and goats. It’s how people developed crops thousands of years ago, too. Around 10,500 BCE, villages in Southwest Asia appear to be the first to have planned and harvested plants that were previously found only in the wild.