Hint: Many genetic diseases are passed on from the parents to the offsprings. They are hereditary diseases. But sometimes some trait or character is suddenly visible in a progeny even though it was not in the parents. This change can be both good and bad. It can also create rare species.
What is a mutation?
Any change in the genetic material or DNA sequence is called a mutation. It can be due to the occurrence of an alteration at the time of DNA copying. Various factors are affecting this copy such as exposure to UV radiation, high temperature, exposure to chemicals, viruses etc.
What does the theory of mutation say?
‘The theory of mutation’ was given by Hugo de Vries in the 20th century. The theory states various points.
- The mutation is random, sudden and inheritable.
- They are the discontinuous variations serving as the raw material for evolution.
- They are irreversible.
- They can occur without any previous indication of their presence.
Note: The individual carrying the mutation is the mutant. There can be DNA mutations like deletion of a DNA base, insertion of a base, substitution and duplication. This can occur at the chromosomal level also. Theory of evolution strikes here as the one that is beneficial to the environment, moreover to itself, can also survive. Sometimes the abilities can be reduced due to mutations while at some time, new characters can also be introduced. This is all occurring in nature, we can’t control it.