Beneficial Effects

Key Concepts

• Mutation
• Beneficial mutation
• Variant
• Evolution

Introduction: 

Beneficial Effects of mutations occur when a DNA gene is damaged or altered in such a way that the genetic message carried by that gene is altered. 

The mutations are not always harmful. 

Beneficial mutations: 

The mutations that have a positive effect on the organism in which they occur are called beneficial mutations.  

They lead to new versions of proteins that help organisms adapt to changes in their environment. Beneficial mutations are essential for evolution to occur. They become common through natural selection. 

 They increase an organism’s chances of surviving or reproducing, so they are likely to become more common over time.  

Explanation: 

• The mutations are beneficial in the following ways: 
• Genetic mutation in organisms leads to evolution. Such an organism that sets itself in a population is called a variant. 
• Through mutations, we learn about the importance of body parts. 
• Mutation produces new proteins that have a novel function and can be useful. 
• The mutations in a few animals help them survive better. In the survival of the fittest, the organisms that undergo mutations become strong. 
• Few mutations help humans to escape the risk of being diseased. 
• The mutations in animals help change their color and hide from their predators. 
• Mutations in a few animals lead to high production of milk or meat. 
• Mutations help to produce hybrid varieties of fruits and flowers. 
• A mutation in bacteria produces nylonase enzyme that digests nylon in wastewater treatment. 

Example 1: 

Long-necked giraffes evolved as they had the advantage of reaching leaves present on tall trees as compared to the other giraffes in the population. 

Such giraffes were more likely to survive and have kids that had longer necks. 

Here the giraffes underwent reproduction, and also the other giraffes that were reproduced had longer necks. 

So, in this way, animals with helpful mutations were more fit to survive and have kids. 

Example 2: 

A mutation in a frog changes its color from white to brown.  

This color helps the frog escape from predators. 

Such mutated frogs are fit for survival. They further reproduce, increase in number, and live longer. 

Example 3: 

Biodegradation is the process by which waste materials decompose. 

But there are many such materials that are not degradable like plastic, tin, glass, etc.  

Plastic takes a very long time, almost 100 years, to degrade. 

Nylon, a type of plastic, also takes a long time to degrade. 

According to recent studies, a mutation in bacteria produces nylonase enzyme that can digest nylon (a type of plastic). 

These bacteria can eat short chains of nylon. Nylonase can be used in sewage treatment.  

Example 4: 

Wild species of almond contained amygdalin, a bitter chemical that converts into cyanide, a toxin inside the human body. 

According to research consuming wild almonds is fatal. 

A single gene mutation in wild almonds gave rise to the varieties that no longer produce amygdalin. 

This discovery helped people produce non-bitter almonds which were further produced and cultivated. 

Example 5: 

Only around one-quarter of the people alive today on this planet can drink milk. 

This was possible due to the beneficial mutation in a gene that helps to digest lactose present in the milk.  

Being able to drink milk as an adult is a recently evolved trait in human beings, and it is called lactose tolerance.  

On the other hand, people who cannot digest lactose are called lactose intolerant. 

Example 6: 

Polyploidy is a condition obtained through mutation where few organisms plant, and animals have more than two complete sets of chromosomes. 

This feature is an advantage to produce new hybrid varieties or species in plants.  

This strawberry in the picture has 8 sets of chromosomes than usual, and hence it is an octoploid. 

It is economically important in agriculture. 

Summary:

• A mutation is a change in genetic material. This means changes in the DNA or the chromosomes that carry the DNA.
• The mutations that have a positive effect on the organism in which they occur are called beneficial mutations.
• They lead to new versions of proteins that help organisms adapt to changes in their environment.
• Beneficial mutations are essential for evolution to occur. They become common through natural selection.
• They increase an organism’s chances of survival or reproduction, so they are likely to become more common over time.
• Mutations in a few animals help them survive better. In the fittest survival, the organisms that undergo mutations become strong.
• Few mutations help humans to escape the risk of being diseased. The mutations in animals help change their color and hide from their predators.
• Mutations in a few animals lead to high production of milk or meat.
• Mutations help to produce hybrid varieties of fruits and flowers.
• A mutation in bacteria produces nylonase enzyme that digests nylon in wastewater treatment