FLIP MUTATION (Syllabus: GS Paper 3 - Sci and Tech)

Context: Recently, researchers at the University of Tokyo revealed that the omicron subvariant JN.1, with a notable mutation in its spike protein known as L455S or "FLip" mutation, is poised to emerge as the predominant lineage of the SARS-CoV-2 virus globally.

Mutation

• About: A mutation is a change in the DNA sequence of an organism. Mutations can result from errors in DNA replication during cell division, exposure to mutagens or a viral infection.
• Types of Chromosomal Mutations: Deletion, Duplication, Inversion, and Translocation.
• Causes: DNA replication errors, Exposure to mutagens, Errors during DNA repair, and Environmental factors.
• Examples: Sickle Cell Anemia, Melanism, and Antibiotic Resistance.

Flip Mutation

• About: This mutation occurs through binary crossover, where a randomly chosen bit within a chromosome is inverted.
• Referred to as "FLip" mutations: Such as L455S and L455F, they are named for their role in swapping the positions of amino acids F and L on the spike protein, thereby enhancing transmissibility.
• Example of the “FLip” Mutation: F456L, which was found in several XBB descendant strains developed this year, such as XBB.1.5.10, FE.1, and FD.1.1.