Delta Variant Sub-lineage AY.12
- According to a report by the Indian SARS-CoV-2 Genomics Consortium (INSACOG), a new sub-lineage AY.12 of the Delta variant of Covid-19 that was recently classified in Israel is now being reported in many parts of India.
- INSACOG is a multi-laboratory, multi-agency, Pan-India network to monitor genomic variations in the SARS-CoV-2 by a sentinel sequencing effort.
Key Points
About:
- INSACOG has pointed out that several cases in India classified as Delta are now being reclassified as AY.12 and these numbers are under close watch.
- The reclassification is primarily to assist micro-epidemiology and is not based on the acquisition of significant mutations. Thus, it is not currently known whether AY.12 is clinically different from Delta.
- While no worrying factors have been found linked to the 12, it has come on INSACOG’s radar as it is said to be driving the surge in Israel despite 60% vaccination in the country.
Delta Variant:
- 1.617.2—also termed the Delta variant—is believed to spread faster than other variants. The Delta variant is highly contagious, more than twice as contagious as previous variants.
- It has birthed several sub-lineages called ‘Delta plus’ variants that bear most of its characteristic mutations but are different in other ways.
The reason behind Delta Variant being more Infectious:
- A key amino acid mutation may be behind the high infectivity of the Delta variant.
- A team of recherars has zeroed in on a key mutation that alters a single amino acid in the SARS-CoV-2 spike protein.
- The change is called P681R and transforms a proline residue into an arginine.
- Arginine is a chemical building block called an amino acid.
Virus Variant
- Proline disrupts protein secondary structure by inhibiting the backbone to conform to an alpha-helix or beta-sheet conformation
- Variants of a virus have one or more mutations that differentiate it from the other variants that are in circulation. While most mutations are deleterious for the virus, some make it easier for the virus to survive.
- The SARS-CoV-2 (Corona) virus is evolving fast because of the scale at which it has infected people around the world. High levels of circulation mean it is easier for the virus to change as it is able to replicate faster.