Related Experiment Videos
Partial nucleotide sequencing and molecular evolution of epidemic causing Dengue 2 strains
1Department of Microbiology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi-110029, India. urvashib@medinst_ernet_in
The Journal of Infectious Diseases
|September 9, 1999
Summary
Genetic analysis of dengue 2 (DEN-2) strains reveals a shift in genotypes. The 1996 Delhi epidemic strains, identified as genotype IV, replaced earlier genotype V strains from 1967.
Area of Science:
- Virology
- Molecular Evolution
- Epidemiology
Background:
- Dengue virus 2 (DEN-2) poses a significant public health threat globally.
- Understanding the genetic diversity and evolutionary dynamics of DEN-2 is crucial for disease control.
Purpose of the Study:
- To investigate the genetic variability and evolutionary changes of DEN-2 strains in Delhi.
- To determine the genotypes of DEN-2 isolates from the 1996 Delhi epidemic and compare them with historical strains.
Main Methods:
- Nucleotide sequencing of the envelope protein gene and nonstructural protein 1 gene junction.
- Phylogenetic analysis using the Molecular Evolutionary Genetics Analysis program.
- Comparison of sequence data with global DEN-2 isolates and prototype strains.
Main Results:
- The 1996 Delhi DEN-2 isolates showed 10%-11% divergence from the 1967 isolate.
- Phylogenetic analysis classified the 1996 isolates as genotype IV.
- The 1967 isolate was classified as genotype V, similar to a 1957 Indian isolate.
Conclusions:
- The study indicates a replacement of earlier DEN-2 genotype V strains by genotype IV in Delhi.
- This genetic shift highlights the dynamic nature of DEN-2 evolution and circulation.