NS2a-NS2b sequence analysis of DEN-4 virus strains

Southeast Asian J Trop Med Public Health. 2003 Sep;34(3):554-8.

Abstract

To study the genetic variability of DEN-4 Chinese isolates, and to trace the origin of DV4 Chinese isolates, we cloned and sequenced the NS2a-NS2b junction of 5 isolates and prototype DV4 (H-241). Our results show that isolates from the 1990 Guangdong epidemic, which were isolated in the early, middle, and late periods of the epidemic, share the same sequence in the NS2a-NS2b junction. The sequence similarity between isolates from the Guangdong epidemic in 1990 and DV4 H-241 is 96%; these isolates can be grouped into genotype I. The sequence similarity between the isolate from the Guangdong epidemic in 1987 and Dominica strain 814669 is 96%; this isolate can be grouped into genotype II. For the first time, our results show that there are also 2 DV4 genotypes in the Guangdong area of southern China, and these isolates perhaps were introduced from other epidemic areas outside of China.

MeSH terms

  • Base Sequence
  • Cell Line
  • China / epidemiology
  • DNA, Complementary / analysis
  • Dengue / epidemiology
  • Dengue / virology*
  • Dengue Virus / genetics*
  • Disease Outbreaks*
  • Genetic Variation*
  • Humans
  • Molecular Sequence Data
  • Viral Nonstructural Proteins / genetics*

Substances

  • DNA, Complementary
  • NS2B protein, flavivirus
  • Viral Nonstructural Proteins