Gene Flow Among Anopheles Albimanus Populations in Central America, South America, and the Caribbean Assessed by Microsatellites and Mitochondrial Dna

Abstract

Gene flow was examined among Anopheles albimanus populations from Cuba, Mexico, Guatemala, El Salvador, Nicaragua, Costa Rica, Panama, Colombia, and Venezuela by examining variation at four microsatellite (MS) loci and a mitochondrial DNA (mtDNA) marker. There was little variation among Central American populations and weak isolation by distance was only observed with the MS loci. There was moderate to large variation between Central and South American populations, suggesting a barrier to gene flow between Central and South America. However, Panamanian and Pacific Costa Rican populations differed with respect to western Central America, suggesting that there may be another barrier within Central America. There was small to moderate variation among Caribbean and continental populations. Phylogenetic and diversity analyses of mtDNA indicate that more ancestral and diverse haplotypes were present in the Caribbean population, suggesting that current continental An. albimanus populations may have originated from the Caribbean.

Genetic Structure of Anopheles (Nyssorhynchus) marajoara (Diptera: Culicidae) in Colombia

“…aegypti from Argentina ( F ST = 0.065) as well as An. albimanus , 49 with F ST values from 0.018 to 0.02 between Central American populations and from 0.057 to 0.082 between South American populations, similar to those shown here. Nevertheless, other species, like several An.…”

Limited Diversity of Anopheles Darlingi in the Peruvian Amazon Region of Iquitos

“…10,12,19,39 The within-population diversity (i.e., expected average heterozygosity across loci) observed in our samples was comparable to previous studies on various Anopheles species in different South and Central American populations. 17 Using various molecular markers, other investigators found similar values of heterozygosity. In three populations of An.…”

“…darlingi can be performed either by using specific primers (as was done in this study) or the use of internal transcribed spacers as described by Marrelli and others. 10 Genetic diversity of Anopheles has been studied using random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR), [11][12][13][14][15] internal transcribed spacer 2 (ITS2) markers, 13,16 microsatellite loci, 17 mitochondrial DNA, 17,18 single nucleotide polymorphism genotyping, 19 and isoenzymatic analysis. 13,20 RAPD-PCR is based on the amplification of random DNA using short sequence primers (approximately 10 bases) at low annealing temperatures.…”

Evidence for Pleistocene Population Divergence and Expansion of Anopheles albimanus in Southern Central America

“…21 In contrast, analysis of microsatellite loci using the same sample localities showed a small effect of distance, but uncovered differences in allele frequencies between Costa Rica and eastern Panama. 22 The discrepancy in allele frequencies may be attributed either to the mountain range that crosses Costa Rica and western Panama, which may act as a barrier to gene flow, or to population contraction in Panama caused by intense insecticide use. 22 Nonetheless, the analysis of only four populations in Costa Rica and Panama in the latter studies may have produced inaccurate results for the IBD analysis, and demographic history (e.g., stability of the population size) and natural selection (e.g., neutrality), which are known to influence inferences of population structure in Anopheles mosquitoes, 8,10 were not explored in these studies.…”

“…22 The discrepancy in allele frequencies may be attributed either to the mountain range that crosses Costa Rica and western Panama, which may act as a barrier to gene flow, or to population contraction in Panama caused by intense insecticide use. 22 Nonetheless, the analysis of only four populations in Costa Rica and Panama in the latter studies may have produced inaccurate results for the IBD analysis, and demographic history (e.g., stability of the population size) and natural selection (e.g., neutrality), which are known to influence inferences of population structure in Anopheles mosquitoes, 8,10 were not explored in these studies. Intensive chemical and physical larval control (e.g., source reduction) was carried out in Panama during and after the construction of the Panama Canal (1904)(1905)(1906)(1907)(1908)(1909)(1910)(1911)(1912)(1913)(1914).…”