Dataset Information

Altitudinal population structure and microevolution of the malaria vector Anopheles cruzii (Diptera: Culicidae).

ABSTRACT: BACKGROUND:In Brazil, the autochthonous transmission of extra-Amazonian malaria occurs mainly in areas of the southeastern coastal Atlantic Forest, where Anopheles cruzii is the primary vector. In these locations, the population density of the mosquito varies with altitude (5-263 m above sea level), prompting us to hypothesise that gene flow is also unevenly distributed. Describing the micro-geographical and temporal biological variability of this species may be a key to understanding the dispersion of malaria in the region. We explored the homogeneity of the An. cruzii population across its altitudinal range of distribution using wing shape and mtDNA gene analysis. We also assessed the stability of wing geometry over time. METHODS:Larvae were sampled from lowland (5-20 m) and hilltop (81-263 m) areas in a primary Atlantic Forest region, in the municipality of Cananéia (State of São Paulo, Brazil). The right wings of males and females were analysed by standard geometric morphometrics. Eighteen landmarks were digitised for each individual and a discriminant analysis was used to compare samples from the hilltop and lowland. A 400-bp DNA fragment of the mitochondrial cytochrome oxidase gene subunit I (CO-I) was PCR-amplified and sequenced. RESULTS:Wing shapes were distinct between lowland and hilltop population samples. Results of cross-validated tests based on Mahalanobis distances showed that the individuals from both micro-environments were correctly reclassified in a range of 54-96%. The wings of hilltop individuals were larger. The CO-I gene was highly polymorphic (haplotypic diversity?=?0.98) and altitudinally structured (?st?=?0.085 and Jaccard?=?0.033). We found 60 different haplotypes but only two were shared by the lowland and hilltop populations. Wing shape changed over the brief study period (2009-2013). CONCLUSIONS:Wing geometry and CO-I gene analysis indicated that An. cruzii is vertically structured. Wing shape varied rapidly, but altitude structure was maintained. Future investigations should identify the biotic/abiotic causes of these patterns and their implications in the local epidemiology of malaria.

SUBMITTER: Lorenz C

PROVIDER: S-EPMC4334843 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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Altitudinal population structure and microevolution of the malaria vector Anopheles cruzii (Diptera: Culicidae).

Lorenz Camila C Marques Tatiani Cristina TC Sallum Maria Anice Mureb MA Suesdek Lincoln L

Parasites & vectors 20141216

<h4>Background</h4>In Brazil, the autochthonous transmission of extra-Amazonian malaria occurs mainly in areas of the southeastern coastal Atlantic Forest, where Anopheles cruzii is the primary vector. In these locations, the population density of the mosquito varies with altitude (5-263 m above sea level), prompting us to hypothesise that gene flow is also unevenly distributed. Describing the micro-geographical and temporal biological variability of this species may be a key to understanding th ...[more]

PMID: 25511160

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Project description:BackgroundAnopheles sinensis is a primary vector for Plasmodium vivax malaria in most regions of China. A comprehensive understanding of genetic variation and structure of the mosquito would be of benefit to the vector control and in a further attempt to contribute to malaria elimination in China. However, there is only inadequate population genetic data pertaining to An. sinensis currently.MethodsGenetic variations and structure among populations of An. sinensis was examined and analyzed based on the nucleotide sequences of a 662 nt variable region of the mitochondrial cox1 gene among 15 populations from 20 collection sites in China.ResultsA total of 453 individuals in 15 populations were analyzed. The cox1 gene sequences were aligned, and 247 haplotypes were detected, 41 of these shared between populations. The range of haplotype diversity was from 0.709 (Yunnan) to 0.998 (Anhui). The genealogic network showed that the haplotypes were divided into two clusters, cluster I was at a high level of homoplasy, while cluster II included almost all individuals from the Yunnan population. The Yunnan population displayed a significantly high level of genetic differentiation (0.452-0.622) and a restricted gene flow with other populations. The pairwise F ST values among other populations were lower. The AMOVA result showed that the percentage of variation within populations (83.83%) was higher than that among populations (16.17%). Mantel test suggested that geographical distance did not significantly contribute to the genetic differentiation (R 2 = 0.0125, P = 0.59). Neutral test and mismatch analysis results showed that the An. sinensis population has undergone demographic expansions.ConclusionsAnopheles sinensis populations showed high genetic polymorphism by cox1 gene. The weak genetic structure may be a consequence of low genetic differentiation and high gene flow among populations, except the Yunnan samples. The Yunnan population was isolated from the other populations, gene flow limited by geographical distance and barriers. These findings will provide a theoretical basis for vector surveillance and vector control in China.

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Dataset Information

Altitudinal population structure and microevolution of the malaria vector Anopheles cruzii (Diptera: Culicidae).

Publications

Altitudinal population structure and microevolution of the malaria vector Anopheles cruzii (Diptera: Culicidae).

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