Back to B6 home
B6 K) Genetic Engineering
B6 K) Genetic Engineering
Genetic engineering involves changing the genome of an organism (genome is the entire genetic material of an organism). Genetic engineering involves transferring a desired gene from one organism to another organism’s genome, which if successful results in the organism receiving the gene having the desired characteristic.
We can genetically modify bacteria to produce human insulin, which can be harvested and given to individuals who have diabetes. We can also genetically engineer crops to be disease resistant, herbicide resistant, produce bigger fruit etc. We will look at some examples of genetically modified organisms after we have looked at the process for genetic engineering.
We can genetically modify bacteria to produce human insulin, which can be harvested and given to individuals who have diabetes. We can also genetically engineer crops to be disease resistant, herbicide resistant, produce bigger fruit etc. We will look at some examples of genetically modified organisms after we have looked at the process for genetic engineering.
How does Genetic Engineering Work?
I am going to use the example of inserting a human insulin gene into a bacterium so that it produces human insulin which can be harvested for diabetic individuals. Genetic engineering uses a vector to transfer the desired gene from one organism to another. The vector used is either a virus or a plasmid; a plasmid is a circular loop of DNA (a plasmid is a circular loop of DNA; this example will involve a plasmid).
Here is the genetic engineering process:
I am going to use the example of inserting a human insulin gene into a bacterium so that it produces human insulin which can be harvested for diabetic individuals. Genetic engineering uses a vector to transfer the desired gene from one organism to another. The vector used is either a virus or a plasmid; a plasmid is a circular loop of DNA (a plasmid is a circular loop of DNA; this example will involve a plasmid).
Here is the genetic engineering process:
- Restriction enzymes isolate (cuts out) the desired gene (the gene for human insulin) and cuts open the plasmid/ vector. The cutting out of the gene and cutting open of the plasmid leaves sticky ends.
- Ligase enzymes then join the sticky ends of the desired gene (human insulin gene) and the plasmid together. This gives us recombinant DNA, which is DNA that has been artificially formed by combining DNA from two different organisms. For our example, the plasmid is now part bacteria DNA and part human DNA (it has the gene for human insulin).
- The recombinant DNA (plasmid with the desired gene) is inserted into a host cell. These host cells are usually bacteria. The host cells will now display the desired characteristic because they now have the gene for the desired characteristic. For our example, the bacteria will start to produce human insulin. The bacteria will then multiply, which results in lots of bacteria cells that can all produce human insulin.
Sometimes the genes are inserted into the cells of the animal, plant or microorganism at an early stage of their development so that the organism can develop with the desired characteristics. The early stage of the organism’s development would be something like an egg or an embryo.
Some Examples of Genetic Engineering
There are many different examples of genetic engineering. Here are some examples:
There are many different examples of genetic engineering. Here are some examples:
- Genetically engineering bacteria to produce human insulin that can be harvested and given to individuals that are diabetic.
- Genetically engineering crops to be resistant to diseases, herbicides and insects. We can also genetically modify crops to change their size, taste or colours of any fruits/ vegetables. Crops that have been genetically engineered are known as genetically modified crops (GM crops). GM crops often produce a larger yield than non-GM crops, which can make farmers more money and help to ensure that there is enough food for everyone.
- Cows and sheep can be genetically modified to produce certain substances in their milk, such as drugs or certain vitamins.
- Rice can be modified to contain certain vitamins/ minerals (golden rice).
- Medical researchers are exploring the possibility of genetic modifications that can overcome some existing inherited disorders. They are looking into the possibility of inserting working genes into individuals that suffer from certain diseases. This avenue of research is known as gene therapy.
Positives & Negatives of Genetic Engineering
Genetic engineering has many positives and negatives. The positives and negatives of genetic engineering depends on what is being genetically engineered.
The main positive of genetic engineering is that we can give organisms certain characteristics that can be extremely beneficial, such as bacteria that produce human insulin. Also, genetic engineering has the potential to solve many global problems, such as food shortages, malnutrition and certain diseases that reduce the quality of life for individuals.
However, there are quite a few concerns that people have with genetic engineering. Some of these concerns are:
Genetic engineering has many positives and negatives. The positives and negatives of genetic engineering depends on what is being genetically engineered.
The main positive of genetic engineering is that we can give organisms certain characteristics that can be extremely beneficial, such as bacteria that produce human insulin. Also, genetic engineering has the potential to solve many global problems, such as food shortages, malnutrition and certain diseases that reduce the quality of life for individuals.
However, there are quite a few concerns that people have with genetic engineering. Some of these concerns are:
- Some campaigners are concerned about how GM crops will affect the number of wildflowers that grow in and around the GM crops. A reduction in wildflowers in and around crops will cause the populations of insects to decrease, which will negatively affect biodiversity.
- Some individuals do not believe that the effects of eating GM crops on human health has been fully explored. These people are worried that eating GM crops could lead to the development of allergies, cancer, immunosuppression etc. However, most scientists believe that eating GM crops has no negative effects on human health.
- There are concerns that the inserted genes could get out into the natural environment. For example, some GM crops have been modified so that they are resistant to herbicides (herbicides are chemicals that are sprayed onto fields to kill weeds). This is beneficial for farmers because they can spray herbicides onto a field to kill weeds without killing the crops. However, some scientists are concerned that the herbicide resistant gene may be transferred from the crops to the weeds, which could create a superweed that is unable to be killed by herbicides – this would be very problematic for farmers growing crops.