South African mutant variation of Corona virus
- February 20, 2021
- Posted by: OptimizeIAS Team
- Category: DPN Topics
South African mutant variation of Corona virus
Subject: Science and Technology
Context: South African variant of corona virus 501Y.V2 has been reported in India and is more transmissible than UK variant.
Concept:
A mutation of the Covid-19 virus was discovered in South Africa and announced in December 2020. Similar to the UK mutation that India has been dealing with this year, the South African strain (501Y.V2) is more transmissible. However, it also affects the younger population more.
Are the vaccines less effective against the mutant variant?
Studies have shown that vaccines developed against the original strain are less effective against the mutant variants, particularly the one from South Africa. Initial studies were conducted only in the laboratory and did not involve human volunteers. They also focused on the UK strain.
Mutations
- The DNA sequence is specific to each organism. It can sometimes undergo changes in its base-pairs sequence. It is termed as a mutation.
- A mutation may lead to changes in proteins translated by the DNA. Usually, the cells can recognize any damage caused by mutation and repair it before it becomes permanent.
Types of Mutations
Silent mutation
- It refers to any change in the sequence of DNA, which has no further impact on the amino acid sequence in a protein or in the functions performed by a protein. There is no phenotypic indicator of mutation.
Nonsense mutation
- When due to a point mutation there is change in the sequence of base pair leading to stop codon. It results in a shortened or non-functional protein.
Missense mutation
- A missense mutation is a result of point mutation leading to change in the codon, which then codes for another amino acid.
Causes:
- Most of the mutations occur when the DNA fails to copy accurately. All these mutations lead to evolution. During cell division, the DNA makes a copy of its own. Sometimes, the copy of the DNA is not perfect and this slight difference is called a mutation.
- When the DNA is exposed to certain chemicals or radiations, it causes the DNA to break down. The ultraviolet radiations cause the thymine dimers to break resulting in a mutated DNA.
Negative effects:
- Genetic disorders can be caused by the mutation of one or more genes. Cystic fibrosis is one such genetic disorder caused by the mutation in one or more genes.
- Cancer is another disease caused by the mutation in genes that regulate the cell cycle.