Table of Contents

  1.  Introduction
    1. What is genetic engineering
    2. The benefits of genetic engineering
    3. Concerns surrounding genetic engineering
  2. What is the genetic engineering used for
    1. Improved crop yield and quality
    2. Reduced use of pesticides and herbicides
    3. Producing new traits in Livestock, Pets, Crops and other typesof organisms
    4. Human modifications
  3. Benefits of Genetic Engineering
    1. Potential benefits of genetic engineering on Human health
    2. Ethical and safety concerns surrounding Genetic Engineering
    3. Safety concerns surrounding gene editing
  4. Concerns about genetically engineered crops
    1. Consumer Rights
    2. Intellectual property rights
    3. Crop interbreeding
    4. Long term ecological effects
  5. Testing for traits unrelated to disease
  6. Building better athletes with gene doping
  7. Conclusion



Genetic engineering is one of those interesting topics that can be intimidating for those who don’t already know about it. Genetic engineering isn’t just interesting, it’s the future for many biological and medicinal fields, and we can expect to reap the benefits of genetic engineering biotechnology in the coming decades. In this guide to genetic engineering biotech, we’ve explained this field of research in simple terms that everybody should be able to understand.

Here you can learn all about genetic engineering through sections that cover every part of this topic. By reading this guide, you’ll learn:

  • The definition and scope of genetic engineering
  • What genetic engineering is broadly used for
  • The benefits of using genetic engineering
  • Concerns surrounding genetic engineering with crops
  • How genetic engineering can be applied to humans
  • Concerns surrounding genetic engineering with humans

If you’re interested in any of these sections, you’ll find the information you want below. While this guide aims to make genetic engineering more understandable, we’ve linked to supporting material where appropriate. There you’ll find more information on certain topics or claims that are raised during this guide, so you can be sure you’re getting accuracy from us.

We should start at the beginning – what is genetic engineering?

What Is Genetic Engineering?

Oxford Languages uses the following definition for genetic engineering:

The deliberate modification of the characteristics of an organism by manipulating its genetic material.

Many laymen can already figure this definition out but it does little to tell us more about what genetic engineering is and how it’s conducted. It should also be noted that biological engineering is often used as a synonym for genetic engineering, so sources discussing biological engineering are often describing the same field of science.

One of the more popular ways that genetic engineering is described is by breaking the term down. For example, genetic engineering is where biological systems are approached with the mind of an engineer. This means you identify ways that biological systems can be improved or better maintained and try to solve those problems through genetic experimentation.

The results of such experimentation are considered a technology or, you guessed it, biotechnology. They usually aim to improve upon four naturally occurring properties in the world:

  • Animal or human health
  • Food sustainability
  • Biological materials
  • Energy production/longevity


One of the smallest and most perennial examples of genetic engineering is where you alter the DNA of some bacteria. By doing this, you change how the bacteria behave. Most bacteria adjustments enable them to create a material, from medicines to color pigments or even forms of plastic. These materials are grown en masse by trillions of bacteria that are then harvested. Without genetic engineering, we wouldn’t be able to alter the bacteria to these ends in the first place.


What Is It Used For?

Let’s go into more detail on what genetic engineering is used for. Understanding how genetic engineering is used can be more useful than knowing the specific scientific processes behind the field when you’re a curious layman.

Genetic Modification of Crops

As humans, we have engaged in genetic modification for thousands of years. How? Well, there weren’t any white lab coats or laboratories required. Instead, the fruits and vegetables that mankind knew thousands of years ago were much different than how they appear now.

Perhaps the most famous example would be the wild banana but most fruits and vegetables have been improved over the years. Check out the wild variants of some of your favorite crops here, where they’re compared to their modern counterparts.

You’ve likely never eaten a fruit or vegetable that wasn’t a product of genetic modification. The specific type of modification used was selective breeding. This is where humans curate the natural breeding process of plants.

It’s very similar to the evolution of animals, where individuals with superior and desirable traits outcompete those without, resulting in all of the species adopting those traits over time. With plants, it was down to us humans to decide which traits were best. If we grew a wild banana that’s full of seeds, but one yield of banana has more edible material inside it, then we discard the wild banana and plant more of the edible banana instead. Many years later, most yellow bananas are nothing but edible with very little seed material in them.

This is a form of genetic modification in its simplest form.

One of the most ancient examples we have is maize. Corn and other related plants are some of the oldest crops we know. Thousands of years ago, in the region we now know as southern Mexico, humans cultivated a wild plant called teosinte. Through selective breeding, they altered this plant into what we call maize. Without realizing it, they were genetically modifying the teosinte until it became something completely different, and much more useful for human agriculture. By only changing an estimated four or five genes, teosinte went from yielding approximately ten grains on a hundred corn ears to a simpler two ears that each housed hundreds of grains.

Besides increasing yield, historic genetic modification of crops has also been used to promote plant diversity. The two most notable examples of this are the wild mustard and wild nightshade plants. Check out how many different fruits and vegetables were created by modifying these wild plants:

Wild Mustard Wild Nightshade
Broccoli Eggplants
Brussel Sprouts Potatoes
Cabbages Tobacco
Cauliflower Tomatoes


To Produce New Traits in Livestock, Pets, Crops, or Other Types of Organism

Whenever there’s a change in the traits displayed by an organism, whether that’s crops or living animals like pets or livestock, it’s because there has been a change in the genetic information of that organism. As covered above, the common breeding practices we’ve used for thousands of years result in genetic differences over time.

How does this simple form of genetic modification compare to genetic engineering today? Selective breeding is naturally a slower and more iterative process when compared to modern gene engineering, where we know what genes affect which traits and how we can change them for the better. Think of selective breeding as a roll of the dice while modern gene engineering is a calculated change.

Human Modifications

As we’ll learn later in this guide, it’s possible to modify the genes of human beings. This is the most impactful and controversial way that genetic engineering is used today and, if the field is allowed to continue, it can change how mankind exists on a fundamental level and how we interact with the world around us.


Benefits Of Genetic Engineering

We practice genetic engineering for several reasons. First, let’s tackle the three most common advantages of genetic engineering when it’s performed on non-human entities.

Advances in Biotechnology May Provide Consumers with Foods that are Nutritionally Enriched

Just like the initial genetic modifications that tamed wild plants hundreds of years ago, genetic engineering is still used today to create food biotechnologies. These biotechnological advances enhance the nutritional content of these foods.

Some genetic engineering can even make perishable food last much longer. We saw one such development in 2010 where the gene-editing of a specific gene added a week of shelf life to tomatoes.

Similarly, research into genetic engineering has also shown ways that naturally occurring toxins can be removed from foods. Many vegetables and fruits contain trace amounts of harmful toxins or allergen materials that can be purged through gene editing. We have also used genetic engineering to reduce the number of saturated fats in oils that we use for cooking. Genes can also be altered to resist diseases common to that plant crop.


Biotechnology May Provide Farmers with Tools that can Make Production Cheaper and More Manageable

Along with altering the traits of crops to make them more palatable and resistant to external pressures, we also develop biotechnology crops that make farming them much easier.

Perhaps one of the most notable and controversial examples of this is crops that have been engineered to tolerate herbicides. Herbicides and pesticides reduce the weeds and pests that harm crops during cultivation and growth. By making crops resistant to these chemicals, they can be used on crops with little worry about making the crop harmful for consumption. Naturally, there are still concerns surrounding GMOs (Genetically Modified Organisms) when they’re used for consumables.

The reduction of farming costs by genetically altering the crops is a massive advantage for countries with agricultural economies since they can create more food for less time and money.


Biotechnology Has Helped to Make Both Pest Control and Weed Management Safer and Easier

Adding weed and pest resistance into the crops themselves, or at least making the crops compatible with non-synthetic alternatives, makes farming a safer profession for those involved. Synthetic pesticides contaminate the land around them, including the water, which can have disastrous effects on the local ecosystem.

Making crops more tolerant to these agents allows the use of more natural herbicides and pesticides that don’t linger in the environment for long. They can be broken down in the soil that the crops grow from with no demonstrable negative effects and without causing any danger to the wildlife or human workers in that area.


Concerns About Genetically Engineered Crops

Given how complex and unpredictable ecological systems can be, we exercise a lot of caution when we tamper with them. This naturally, and beneficially, raises concerns about genetically engineered crops and consumables as we want the solutions to our short-term problems to be both sustainable and healthy for us all in the long term. What may seem healthy and problem-free at first can have devastating effects decades later.

This is why critics of genetically engineered crops consistently advocate that precautions and considerations are taken before any gene altering is performed. By altering a gene in a commonly consumed vegetable, there could be unintended consequences that affect the environment around it in a negative way.

These activists tend to target modern genetic engineering but it should also be considered that selective breeding, though slower and cruder, is also fundamentally a gene-editing process that could deliver the same negative outcomes. This is why proponents of genetic engineering skepticism also sometimes advise that traditionally produced crops are also studied to see if their newer forms harmed the environment and the people in it.

Our primary source for this section comes from the US National Academies of Sciences, Engineering, and Medicine. In 2016, they published the most comprehensive report to date that addresses the concerns surrounding genetic engineering crops. Spanning 500 pages and reviewing over 900 research articles in the field, the Genetically Engineered Crops: Experiences and Prospects report is the most information we have.

As is the nature of scientific research, the facts surrounding genetic engineering are subject to change as more findings are submitted and verified. Note that the report does include human effects from genetically engineered crops but, since we’ve talked about human gene engineering below, we’ve included the information there.

That said, here’s what this report has to say about crop concerns.

Consumer Rights

Let’s start with an ethical boundary that genetic engineering crosses in many farming circles. While all modern consumed crops have been selectively bred, advocates highlight the consumer’s right to choose 100% organic foods that have been untouched by modern genetic engineering.

The report found that many US farmers, who only grew organic crops, have detectable levels of genetic editing in their plants. The fact this was present even in seed matter points to the issue being more pervasive, as the seeds many organic farmers use have been edited in some way, somewhere along that plant’s lineage.

Nowadays, the term organic and any organic certification used in the farming industry instead highlights that the farms are free of these methods. Unfortunately for organic consumers who don’t want to consume any altered material, many of the seeds in circulation have come from altered crops and find their way onto organic farms.

To become certified as organic, any genetic engineering must be confirmed to have come from outside the farm. The report estimates that pollen drift between adjacent crops could even be responsible for transmitting genetically engineered material into otherwise organic crops. It’s a problem that’s difficult and impractical to solve, and so while some suppliers are more organic than others, it can never be 100% guaranteed that seeds are free from genetic engineering.

Intellectual Property Rights

Similarly, the rights of the business entities creating and growing genetically engineered crops must be considered. A naturally occurring crop has existed in, well, nature for hundreds of years, and has been cultivated by our ancestors during that time. In a way, they belong to all of us. A genetically engineered crop, however, is technically invented.

That means patents and lots of them. The agriculture business files patents over genetically engineered crops but, in doing so, they risk taking something that everybody can benefit from and safeguarding it or outright blocking further development of a crop. This allows companies to control the pricing of certain seeds, harming the many for the sake of the few.

Of course, the report aimed more at tackling biotechnological concerns surrounding genetic engineering in crops, so they don’t dedicate much ink to this particular issue. That said, they do recommend more research by watchdogs and free-market advocates into how these companies can fix prices and establish undue control over a crop.

If these ideas are interesting to you, Harvard has you covered with this primer on genetically engineered crop patents.

Crop Interbreeding

Next in the list of concerns is interbreeding, also called hybridization. This is where crops mix their genetic material with wild relatives existing in the same ecosphere. By doing this, the wild relatives nearby are changed through second-hand transmission, as the gene-editing that has occurred often wins out over natural processes. From there, this can disrupt the food chain or have other damaging consequences in the long term.

The example found in the report uses herbicide-resistant genetic engineering to explain that if a plant transmitted this trait over to a wild relative, then that relative becomes resistant too. Now, what if that relative is a weed that is controlled by herbicides? Now we have fewer means of controlling it which, in turn, could displace animals and plant life in the area.

The report found some evidence that such transmission had occurred. What they did not find was any demonstrable, appreciable harm from those transmissions. That doesn’t rule out the possibility, however, and so it’s wise and prudent that wild relatives that get affected by new crops should be studied over longer periods.

Long-Term Ecological Effects

Speaking of longer periods, the report also tackles issues relating to other long-term effects. An example cited in the report is the tale of Bt corn and monarch butterflies. There have been several studies covering this specific issue, read a popular one here, but the short story is that altered corn called Bt corn makes a protein to perform the role of an insecticide. The theory is that pollen from Bt corn harms caterpillars, specific monarch butterfly caterpillars, and so they suffer as collateral when this genetic engineering is performed.

Initial studies found that there was only harm when there were very high concentrations of this affected pollen. In natural conditions, there wasn’t enough of a pollen count to create any negative effects. The first studies were questioned by other researchers and, as the report details, other larger studies took place to get to the heart of this issue.

Their findings were largely the same but there was an important caveat. Amongst different strains of Bt corn, there was one that posed some threat to monarch butterflies. It was removed from the market because of these concerns while allowing the farming community to reap the benefits of safe Bt corn.

Human Genetic Engineering

So far, we’ve referenced genetic engineering regarding most crops and other plant life. That’s because they’re the easiest and most widespread example of organisms where their genes have been engineered towards specific purposes. That said, they’re not the only ones.

Human genetic engineering has existed for several decades now and with it comes a whole new raft of benefits and concerns. Let’s break them down here.


Testing for Traits Unrelated to Disease

Most genetic engineering research on humans comes from identifying and eliminating diseases. Human gene engineering has proven invaluable at finding diseases in at-risk individuals or carriers before any of them are symptomatic or transmissive.

There are concerns, however, like if that testing is helpful if the disease cannot be cured. Would you rather know you’ll develop an incurable condition in later life or live in blissful ignorance of that fact for most of your life? The answer seems too personal to be explained through a scientific study, as people have reported both yes and no when asked.

By identifying these diseases at a genetic level, we opened a can of worms since we could now identify non-disease genes. Tests are now possible for eye color, which hand will be dominant, the potential for addictions, and athleticism. Knowing of these traits may be harmful to somebody who doesn’t conform to them if they’ve had these tests run. People tend to want to attribute their accomplishments to themselves and their decisions over predetermined genetic information, after all.

From these revelations come two other controversial uses of human genetic engineering


Building Better Athletes with Gene Doping

For as long as there have been athletes, there have been performance enhancers that athletes have used to get ahead of the game. Genetic engineering may have a part to play here, too.

The World Anti-Doping Agency tries to police doping in the world’s largest sporting events but they have a new issue that doesn’t have a clear solution. So-called gene doping is where athletic performance is improved through gene therapy. This is usually used to transfer healthy genes to a sick person to aid in recovery or tame an immunological condition but, through gene doping, athletes can maximize hormone and protein production in a way that can’t easily be tested for.

This possibility has been known for years. In the 1990s, a batch of mice was awarded muscle mass through gene therapy and became known as the “Schwarzenegger Mice.”

What isn’t known is whether gene doping can have more harmful consequences. Tinkering with genes, especially those dictating hormone and protein production regarding athletic performance, could have devastating consequences in the long term for those athletes. There’s also the ethical question and whether this should be considered the same as drug doping at all, or whether it’s something to embrace and explore for other applications.

Creating Designer Babies

You’ve likely heard the term designer babies before. If not, this is where genetic testing and altering are used to promote certain human traits over others before the full development and birth of the child. If that sounds like eugenics to you, that’s because it is.

Existing in the field of eugenics doesn’t make the practice abhorrent in itself, of course. While atrocities like forced sterilization have been performed in the name of eugenics, it’s a field that we will inevitably have to engage with when discussing the genetic engineering of human beings. 

Some reject designer babies on this principle, as is their right, but the fear of designer babies is more focused on what the next logical steps are. Gene testing is used to eliminate specific, severe diseases from embryos before they can manifest. Most agree that this is a good and valid use of genetic engineering, the fear is that it will then get used on non-disease traits, hence the term designer babies.

There’s a far cry between eliminating life-threatening diseases from an embryo and tweaking with one so that they have blonde hair instead of brown hair. It’s a sensationalized issue but still one that should be acknowledged when discussing human gene engineering.

There’s also the added risk of causing unforeseen issues in the child as a result. Like with crops, one gene change could have a chain reaction effect and change the organism in ways that we simply cannot predict. This is the cutting edge of genetic engineering research, so there haven’t been enough test subjects or years passed since those tests to ensure that it’s a safe procedure.

There’s also the ethical concern about liberty. While a hands-off approach to a child’s biological circumstance is ethically sound, the decision made by an adult to alter the child is something that the child cannot consent to. A child would likely consent to a life-saving edit if they could but other changes would be done without that child’s permission.

Designer babies, as a term, also highlight how such breakthrough tech is affordable only by the elite. The average person won’t be able to create their ideal child and this can exaggerate class issues and create a class of people who have been altered to ensure they have higher potential for physical attractiveness or intellectual aptitude over unedited people. This has been referred to as the genetic aristocracy. Novels like Brave New World and movies like Gattaca and are often brought up to evidence how such genetic engineering is a step towards a dystopia.

Naturally, all of these thoughts are hypothetical as of now. The invention of CRISPR technology has brought us closer to this reality than ever before but even then, it may still prove too complex, and so impossible, to alter one non-diseased human gene to any appreciable effect.

Human Health Risk

There are also human health risks to be associated with genetic engineering. The most prevalent and likely today would be from genetically engineered crops which then, after entering our systems, cause an adverse reaction in our biology.

Crop biotechnology may contain a higher quantity of or altered allergens that can harm people and animals. While this has proven to be an issue for animals, the widespread consensus is that genetically engineered crops are safe for consumption and that selective breeding can result in the same negative effects.

In fact, this was an issue that was settled quite some time ago and we haven’t seen any issues since. Many of the largest organizations have cleared GMOs of health risks. That doesn’t mean we shouldn’t keep the possibility of health risks in mind, however, as the scientific process remains open to new evidence.

As for the report cited above, they found that engineered crops had the same health risks as organic crops, failing to establish a causal relationship between gene engineering and any adverse reactions or environmental issues. After over two decades of consuming genetically engineered crops, we have yet to see an increase in adverse reactions.

Any new traits found in edible plant biotechnology are examined by the FDA before hitting any market. There they can rule out allergic responses and other toxic effects from the new proteins responsible for those traits.

Genetically engineered food can also harm humans by disrupting the food chain. For example, pest-resistant biotech crops could disrupt or harm worms, bees, or fish. All three of these perform important environmental functions that could have long-term consequences for human beings. Bees alone are incredibly important to the world’s crops.



By now, you should have an understanding of what genetic engineering is and how we apply it in the world, whether that’s when we eat a vegetable or perform expensive, groundbreaking, and controversial human gene editing. Through genetic engineering, we can change how we interact with the world on a molecular level and negotiate for a better deal, by improving crops or even removing diseases from people when they’re embryos.

It’s an exciting field of research that’s sure to continue development into the future. When any advancements are made in the field, you can appreciate them sooner now that you know what genetic engineering is and how it influences our daily lives.