Genetic engineering

Genetic engineering is a way to change the genetic makeup of a living thing. Scientists use special tools to add, remove, or change DNA. DNA is the code that tells a cell how to work. This method is much faster than old ways of breeding. In traditional breeding, people cross plants or animals many times to get a result. Genetic engineering can take a single gene from one organism and put it into another.

This can create new or improved living things. We call these genetically modified organisms, or GMOs. If a gene comes from a different species, the organism is called transgenic. If the gene is from the same species, it is called cisgenic.

How does this work step by step? First, scientists must get the new DNA they want to use. They can do this by copying genetic material or by making it from scratch. This new piece of DNA is often called a construct. Next, the scientists must put this DNA into a host organism. They might use a method called micro-injection to put it into a cell. They can also use a vector system to carry the DNA inside.

Sometimes, they can even use a gene gun to shoot DNA into cells. This process can add new traits or even "knock out" a gene to remove it.

This science has a very interesting history. In 1972, Paul Berg designed the first recombinant DNA molecule. He combined DNA from a monkey virus with a lambda virus. In 1973, Herbert Boyer and Stanley Cohen created the first transgenic organism. They did this by putting genes into an E. coli bacterium. Later, in 1974, Rudolf Jaenisch created the first GM animal. He did this by putting foreign DNA into a mouse.

In 1976, the first company for this work, Genentech, was started. By 1978, they successfully produced human insulin using this technology.

There are many real-world uses for these tools today. In 1982, insulin-producing bacteria were sold for medical use. In 1994, the first GM food, the Flavr Savr tomato, was sold. This tomato was made to stay fresh for a longer time. Most modern GM crops are made to resist insects or herbicides. In 2003, people could even buy GloFish as pets. In 2016, scientists sold salmon that had been modified with a growth hormone.

These tools also help make mRNA vaccines to prevent infections like COVID-19. They even help make enzymes for laundry detergent and cheese.

Even though this science is helpful, it can be a hard job to manage. Some people worry about the safety of GM food. They also worry about how it might affect other living things in nature. Because of these concerns, many countries have rules to keep things safe. A group of rules called the Cartagena Protocol on Biosafety was adopted in 2000. Different countries have different rules, especially the United States and Europe. These rules help scientists study gene function while keeping people safe. This work helps us understand the very building blocks of life.