Delta Variant Sub-lineage AY.12 | 26 Aug 2021

Why in News

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 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 AY.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:
  
  • B.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.
• 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.
    • Proline disrupts protein secondary structure by inhibiting the backbone to conform to an alpha-helix or beta-sheet conformation

Source: TH