New variant B.1.1.529
- November 26, 2021
- Posted by: OptimizeIAS Team
- Category: DPN Topics
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New variant B.1.1.529
Context: A new variant of the coronavirus that causes Covid-19 — called B.1.1.529 — has been identified in South Africa, with officials there saying it’s of concern. Fears a new strain could fuel outbreaks in many countries,
Concept:
- 1.1.529 carries a high number of mutations in its spike protein, which plays a key role in the virus’ entry into cells in the body. The beta variant, a mutation identified last year in South Africa, also may have come from an HIV-infected person.
- Viruses mutate all the time, with the changes sometimes making the virus weaker or sometimes making it more adept at evading antibodies and infecting humans.
- The WHO called a meeting on Friday to discuss B.1.1.529 and decide if it will be officially designated a variant of interest or concern. If it does, it will receive a Greek letter name under the WHO naming scheme, likely the letter “nu.
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.