Article

Genetic relationships among Aedes aegypti collections in Venezuela as determined by mitochondrial DNA variation and nuclear single nucleotide polymorphisms.

Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado 80523-1682, USA.
The American journal of tropical medicine and hygiene (impact factor: 2.59). 04/2008; 78(3):479-91. pp.479-91
Source: PubMed

ABSTRACT A population genetic analysis of gene flow was conducted among 619 Aedes aegypti from nine collections distributed among six geographic regions of Venezuela. Genetic markers included a 387-basepair region of the mitochondrial NADH dehydrogenase 4 (ND4) gene and single nucleotide polymorphisms (SNPs) at 11 nuclear loci. Genotypes at SNP loci were identified using melting curve analysis. Six different ND4 haplotypes were detected and patterns of variation suggested that collections were isolated by distance. The variance in SNP allele frequencies was much less than the variance in haplotype frequencies and a pattern of isolation by distance was not detected. Aedes aegypti from eight collections were orally challenged with dengue 2 virus. Disseminated infection rates ranged from 77% to 95%. The percentage of mosquitoes exhibiting a midgut infection barrier ranged from 2% to 15%, and those exhibiting a midgut escape barrier ranged from 2% to 18%. Venezuelan Ae. aegypti appear to be susceptible to dengue virus infection.

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Keywords

11 nuclear loci
 
619 Aedes aegypti
 
Aedes aegypti
 
aegypti
 
dengue 2 virus
 
dengue virus infection
 
different ND4 haplotypes
 
Disseminated infection rates
 
gene flow
 
Genetic markers
 
haplotype frequencies
 
midgut infection barrier
 
mitochondrial NADH dehydrogenase 4
 
population genetic analysis
 
single nucleotide polymorphisms
 
SNP allele frequencies
 
SNP loci
 
SNPs
 
variance
 
Venezuelan Ae
 

Ludmel Urdaneta-Marquez