If you’re like many people, you probably have an opinion, or at least a feeling, about genetic engineering, but you might have a difficult time answering if someone asked you what exactly genetic engineering is. To help boost your knowledge, read on for answers to some of the most frequently asked questions about this complex subject.
What is genetic engineering?
Simply put, genetic engineering is the process of using technology to directly manipulate or change the genetic makeup of a living organism, whether plant, animal, or bacteria. In other words, it is the process of altering the DNA within an organism’s genome; a genome is the set of all the genes in a particular organism.
How does genetic engineering work?
Genetic engineering has been made possible by significant advances in technology over the last three or four decades, along with our ever more sophisticated understanding of biological systems. Essentially, we now know that every living cell contains DNA, a molecule made up of four subunits: adenine, thymine, guanine, and cytosine. The order of the subunits within each strand of DNA serves as a kind of code of information for the cell, giving it instructions on how to make the different proteins that an organism needs to live and grow. Proteins do the work in cells: they can regulate reactions taking place in the cell, or they can speed up reactions by acting as enzymes. Every part of an organism is either made of proteins, or has resulted from a protein action.
Small segments of DNA are known as genes, and each gene contains instructions for how to produce one specific protein. In the process of genetic engineering, a gene is physically removed from one organism—we can think of this quite literally as cutting a small piece of DNA out of the larger strand—and manually inserted into a gap in the DNA of another organism. This means that whatever protein-making instructions that gene contained will be transferred to the new organism. In other words, the new organism will now be able to express whatever trait is encoded in the transferred gene.
Is genetic engineering the same thing as cloning?
Even though cloning techniques are used in genetic engineering, the two processes are not the same. Cloning technology aims to produce an exact genetic copy of an organism, and only makes use of genes copied within the same species. Genetic engineering, on the other hand, makes a deliberate modification to an organism’s genome by transferring genes from one organism to another, either within or across species. The result of genetic engineering is a unique set of genes rather than a genetically identical copy.
Why is genetic engineering used?
The main purpose of genetic engineering is to produce new organisms designed to fulfill a specific purpose; some might say that the idea is to produce “better” versions of existing organisms, or new versions of existing organisms that contain beneficial traits. For example, a genetically engineered organism might now be able to produce a useful substance, or to carry out a new function.
This desire to improve an organism’s traits is not new. For centuries, people have been using selective (or “traditional”) breeding techniques in plants and animals to produce offspring with particular combinations of traits. However, genetic engineering allows us to take the process to a much deeper level, creating combinations of traits that are not found in nature and controlling them with much more precision.
Where am I most likely to see examples of genetic engineering?
Genetic engineering is at work in a great many fields today. One area where genetic engineering is widely practiced, and where the average consumer is most likely to see genetically modified organisms, is in agriculture and food production. Scientists are looking for ways to improve different agricultural crops by making them more resistant to damage from pests, disease, or adverse environmental conditions; enhancing their growth rate; and boosting their nutritional value and, in some cases, their flavor.
One example of genetic engineering that you may already have encountered in your local grocery store is the HoneySweet plum. Here, genetic engineering was used to develop a variety of plum that would be resistant to plum pox virus (PPV), a type of virus that affects stone fruit trees such as plums, peaches, and cherries. As there are few sources of natural resistance to PPV, scientists used genetic engineering techniques to introduce a resistance gene into a variety of European plum. The resulting new plum, the HoneySweet, is now resistant to PPV.