tailieunhanh - Báo cáo y học: " Evolution of Dengue Virus Type 3 Genotype III in Venezuela: Diversification, Rates and Population Dynamics"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Evolution of Dengue Virus Type 3 Genotype III in Venezuela: Diversification, Rates and Population Dynamics | Ramirez et al. Virology Journal 2010 7 329 http content 7 1 329 VIROLOGY JOURNAL RESEARCH Open Access Evolution of Dengue Virus Type 3 Genotype III in Venezuela Diversification Rates and Population Dynamics 1Ỷ 2Ỷ 1 1 1 3 Alvaro Ramirez Alvaro Fajardo Zoila Moros Marlene Gerder Gerson Caraballo Daria Camacho 3 v 4 z 4 2 s2 Guillermo Comach Victor Alarcón Julio Zambrano Rosa Hernández Gonzalo Moratorio Juan Cristina Ferdinando Liprandi1 Abstract Background Dengue virus DENV is a member of the genus Flavivirus of the family Flaviviridae. DENV are comprised of four distinct serotypes DENV-1 through DENV-4 and each serotype can be divided in different genotypes. Currently there is a dramatic emergence of DENV-3 genotype III in Latin America. Nevertheless we still have an incomplete understanding of the evolutionary forces underlying the evolution of this genotype in this region of the world. In order to gain insight into the degree of genetic variability rates and patterns of evolution of this genotype in Venezuela and the South American region phylogenetic analysis based on a large number n 119 of envelope gene sequences from DENV-3 genotype III strains isolated in Venezuela from 2001 to 2008 were performed. Results Phylogenetic analysis revealed an in situ evolution of DENV-3 genotype III following its introduction in the Latin American region where three different genetic clusters A to C can be observed among the DENV-3 genotype III strains circulating in this region. Bayesian coalescent inference analyses revealed an evolutionary rate of X 10-4 substitutions site year s s y for strains of cluster A composed entirely of strains isolated in Venezuela. Amino acid substitution at position 329 of domain III of the E protein A V was found in almost all E proteins from Cluster A strains. Conclusions A significant evolutionary change between DENV-3 genotype III strains that circulated in the initial years of the introduction in the continent and .