Bio technology
Biotechnology is the use of an organism, or a component of an organism or other biological system, to make a product or process.
Many forms of modern biotechnology rely on DNA technology.
DNA technology is the sequencing, analysis, and cutting-and-pasting of DNA.
Common forms of DNA technology include DNA sequencing, polymerase chain reaction, DNA cloning, and gel electrophoresis.
Biotechnology inventions can raise new practical concerns and ethical questions that must be addressed with informed input from all of society.
Introduction
What do you think of when you hear the word “biotechnology”? Maybe things you’ve seen in the news, such as Dolly the cloned sheep, genetically modified organisms, or gene therapy.
The stuffed remains of Dolly the sheep. Dolly was the first cloned mammal. That is, she was a genetically identical "copy" of another sheep.
Image modified from "Dolly the sheep, National Museums of Scotland, Edinburgh," by Mike Pennington (CC BY-SA 2.0). The modified image is licensed under a CC BY-SA 2.0 license.
If that's what you think of, you’re absolutely right: these are all examples of biotechnology. But what about beer-brewing, crop breeding, and the antibiotic penicillin? These processes and products – some of which have been around for thousands of years – are also examples of biotechnology.
In this article, we’ll first examine the definition of biotechnology, seeing how it can encompass many different uses of organisms (and molecules or systems derived from organisms) to produce useful products. Then, we’ll take a closer look at DNA technology, techniques for manipulating and sequencing DNA. DNA technology is crucial to many modern forms of biotechnology.
What is biotechnology?
Biotechnology is the use of an organism, or a component of an organism or other biological system, to make a product or process for a specific use.
This is a very broad definition, and as mentioned above, it can include both cutting-edge laboratory techniques and traditional agricultural and culinary techniques that have been practiced for hundreds of years. Let’s look at three examples of biotechnology and see how they fit the definition:
Beer brewing. In beer brewing, tiny fungi (yeasts) are introduced into a solution of malted barley sugar, which they busily metabolize through a process called fermentation. The by-product of the fermentation is the alcohol that’s found in beer. Here, we see an organism – the yeast – being used to make a product for human consumption.
Penicillin. The antibiotic penicillin is generated by certain molds. To make small amounts of penicillin for use in early clinical trials, researchers had to grow up to 500500500liters of “mold juice” a week^11start superscript, 1, end superscript. The process has since been improved for industrial production, with use of higher-producing mold strains and better culture conditions to increase yield^22start superscript, 2, end superscript. Here, we see an organism (mold) being used to make a product for human use – in this case, an antibiotic to treat bacterial infections.
Image of a metal block with a glass window, containing a sample of penicillin-producing mold. The block was given by Alexander Fleming to Douglas Macleod.
Image modified from "Sample of penicillin mould presented by Alexander Fleming to Douglas Macleod," (CC BY-SA 2.0). The modified image is licensed under a CC BY-SA 2.0 license.
Gene therapy. Gene therapy is an emerging technique used to treat genetic disorders that are caused by a nonfunctional gene. It works by delivering the “missing” gene’s DNA to the cells of the body. For instance, in the genetic disorder cystic fibrosis, people lack function of a gene for a chloride channel produced in the lungs. In a recent gene therapy clinical trial, a copy of the functional gene was inserted into a circular DNA molecule called a plasmid and delivered to patients’ lung cells in spheres of membrane (in the form of a spray)^33start superscript, 3, end superscript.
In this example, biological components from different sources (a gene from humans, a plasmid originally from bacteria) were combined to make a new product that helped preserve lung function in cystic fibrosis patients.
As these examples show, biotechnology is used in the production of products we see in everyday life, such as alcohol and penicillin. It can also be used to develop new medical treatments, such as the gene therapy treatment for cystic fibrosis. Biotechnology has additional applications in areas such as food production and the remediation (cleanup) of environmental pollution.
What is DNA technology?
Many examples of modern biotechnology depend on the ability to analyze, manipulate, and cut and paste pieces of DNA. Approaches for the sequencing and manipulation of DNA are sometimes referred to as DNA technology^44start superscript, 4, end superscript. For example, for the cystic fibrosis gene therapy trial, researchers used DNA manipulation techniques to insert the chloride channel gene into a piece of carrier DNA (a vector) that allowed it to be expressed in human lung cells.
DNA technology is important to both basic and applied (practical) biology. For instance, a technique used to make many copies of a DNA sequence, called polymerase chain reaction (PCR), is used in many medical diagnostic tests and forensics applications as well as in basic laboratory research.
Examples of DNA technologies
- DNA cloning. In DNA cloning, researchers “clone” – make many copies of – a DNA fragment of interest, such as a gene. In many cases, DNA cloning involves inserting a target gene into a circular DNA molecule called a plasmid. The plasmid can be replicated in bacteria, making many copies of the gene of interest. In some cases, the gene is also expressed in the bacteria, making a protein (such as the insulin used by diabetics).
- Polymerase chain reaction (PCR).Polymerase chain reaction is another widely used DNA manipulation technique, one with applications in almost every area of modern biology. PCR reactions produce many copies of a target DNA sequence starting from a piece of template DNA. This technique can be used to make many copies of DNA that is present in trace amounts (e.g., in a droplet of blood at a crime scene).
- Gel electrophoresis. Gel electrophoresis is a technique used to visualize (directly see) DNA fragments. For instance, researchers can analyze the results of a PCR reaction by examining the DNA fragments it produces on a gel. Gel electrophoresis separates DNA fragments based on their size, and the fragments are stained with a dye so the researcher can see them.
- DNA sequencing. DNA sequencing involves determining the sequence of nucleotide bases (As, Ts, Cs, and Gs) in a DNA molecule. In some cases, just one piece of DNA is sequenced at a time, while in other cases, a large collection of DNA fragments (such as those from an entire genome) may be sequenced as a group.
In the linked sections, you can see how these techniques work in more detail. You can also see examples of how they are used in research, medicine, and other practical applications.Biotechnology raises new ethical questions
Biotechnology has the potential to provide benefits to people and societies, but it can also have negative effects or unintended consequences. This is true of all forms of technology, not just biotechnology. However, biotechnology can offer different types of benefits and pose different types of dilemmas than other forms of technology.It is important that biotechnology innovations (like other technological innovations) be carefully tested and analyzed before they are released for general use. Clinical trials and government regulation help ensure that biotechnology products placed on the market are safe and effective. However, sometimes new information becomes available that makes companies and government agencies reconsider the safety or utility of an innovation. We see this happening when a medication is occasionally withdrawn from the market.In addition, biotechnology innovations may raise new ethical questions about how information, techniques, and knowledge should or shouldn’t be used.- Some of these relate to privacy and non-discrimination. For instance should your health insurance company be able to charge you more if you have a gene variant that makes you likely to develop a disease? How would you feel if your school or employer had access to your genome?
- Other questions relate to the safety, health effects, or ecological impacts of biotechnologies. For example, crops genetically engineered to make their own insecticide reduce the need for chemical spraying, but also raise concerns about plants escaping into the wild or interbreeding with local populations (potentially causing unintended ecological consequences).
- Biotechnology may provide knowledge that creates hard dilemmas for individuals. For example, a couple may learn via prenatal testing that their fetus has a genetic disorder. Similarly, a person who has her genome sequenced for the sake of curiosity may learn that she is going to develop an incurable, late-onset genetic disease, such as Huntington's.
Scientific research and development can make new information, techniques, and knowledge available. However, science alone cannot answer questions about how these techniques should or shouldn’t be used. It's important for all members of society to have their voices heard in the conversation about biotechnology inventions and products that can affect our everyday lives.
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