title: Population structure analyses and demographic history of the malaria vector Anopheles albimanus from the Caribbean and the Pacific regions of Colombia.
abstract: BACKGROUND
  Anopheles albimanus is an important malaria vector in some areas throughout its distribution in the Caribbean and the Pacific regions of Colombia, covering three biogeographic zones of the neotropical region, Maracaibo, Magdalena and Chocó.
  
  
  METHODS
  This study was conducted to estimate intra-population genetic diversity, genetic differentiation and demographic history of An. albimanus populations because knowledge of vector population structure is a useful tool to guide malaria control programmes. Analyses were based on mtDNA COI gene sequences and four microsatellite loci of individuals collected in eight populations from the Caribbean and the Pacific regions of Colombia.
  
  
  RESULTS
  Two distinctive groups were consistently detected corresponding to COI haplotypes from each region. A star-shaped statistical parsimony network, significant and unimodal mismatch distribution, and significant negative neutrality tests together suggest a past demographic expansion or a selective sweep in An. albimanus from the Caribbean coast approximately 21,994 years ago during the late Pleistocene. Overall moderate to low genetic differentiation was observed between populations within each region. However, a significant level of differentiation among the populations closer to Buenaventura in the Pacific region was observed. The isolation by distance model best explained genetic differentiation among the Caribbean region localities: Los Achiotes, Santa Rosa de Lima and Moñitos, but it could not explain the genetic differentiation observed between Turbo (Magdalena providence), and the Pacific region localities (Nuquí, Buenaventura, Tumaco). The patterns of differentiation in the populations from the different biogeographic provinces could not be entirely attributed to isolation by distance.
  
  
  CONCLUSIONS
  The data provide evidence for limited past gene flow between the Caribbean and the Pacific regions, as estimated by mtDNA sequences and current gene flow patterns among An. albimanus populations as measured by MS loci which may be mainly influenced by semi-permeable natural barriers in each biogeographical region that lead to the genetic differences and effective population sizes detected. The relatively high genetic differentiation in the port city of Buenaventura may be the result of specific ecological conditions, human migration and activities and/or differences in effective population sizes. This knowledge could serve to evaluate and coordinate vector control strategies in these regions of Colombia.
authors.affiliation: Grupo de Microbiología Molecular, Escuela de Microbiología, Universidad de Antioquia, Medellín, Colombia. liangutibui@gmail.com
authors.forename: Lina A
authors.initials: LA
authors.lastname: Gutiérrez
authors.forename: Nelson J
authors.initials: NJ
authors.lastname: Naranjo
authors.forename: Astrid V
authors.initials: AV
authors.lastname: Cienfuegos
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Muskus
authors.forename: Shirley
authors.initials: S
authors.lastname: Luckhart
authors.forename: Jan E
authors.initials: JE
authors.lastname: Conn
authors.forename: Margarita M
authors.initials: MM
authors.lastname: Correa
mesh_terms: D000818:Animals; D000852:Anopheles / Q000145:classification / Q000235:genetics*; D017691:Caribbean Region; D003105:Colombia; D004272:DNA, Mitochondrial / Q000235:genetics*; D003710:Demography; D003576:Electron Transport Complex IV / Q000235:genetics*; D019143:Evolution, Molecular; D005787:Gene Frequency / Q000235:genetics; D014644:Genetic Variation / Q000235:genetics*; D005838:Genotype; D006801:Humans; D007303:Insect Vectors / Q000145:classification / Q000235:genetics*; D008288:Malaria / Q000635:transmission; D018895:Microsatellite Repeats / Q000235:genetics*; D009154:Mutation; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D017422:Sequence Analysis, DNA
chemical_list: D004272:DNA, Mitochondrial; D003576:Electron Transport Complex IV