Biomaterial Database

Temporal and geographic genetic variation in Culex pipiens quinquefasciatus (Diptera: Culicidae) from Florida. 2003

Jai K Nayar, and J W Knight, and L E Munstermann

Florida Medical Entomology Laboratory, Department of Entomology and Nematology, Institute of Food and Agricultural Sciences, University of Florida, 200 9th St., S.E., Vero Beach, FL 32962, USA.

Culex (Culex) pipiens quinquefasciatus Say field population from Vero Beach, FL, sampled monthly over a period of 8 mo, a colony sample, and six geographic samples were analyzed for genetic variation at 12 enzymes (10 "neutral" gene enzymes with 11 putative loci and two "complex" gene enzymes) by using polyacrylamide gel electrophoresis. The analysis of the 11 putative loci in both temporal and geographic samples showed that the four loci (Gpi, Hk, Mdhp-2, and Pgm) diagnostic of Cx. p. quinquefasciatus in the southern United States are present in similar frequencies in Florida samples. The Cx. p. quinquefasciatus colony sample showed significantly lower genetic variation than the temporal field samples, measured by mean number of alleles per locus (colony 1.2 +/- 0.1 versus field 1.44 +/- 0.03), percentage of polymorphic loci (colony 18.2% versus field 28.4%), mean observed heterozygosity (H(o) = colony 0.027 +/- 0.02 versus field 0.09 +/- 0.01), and mean Hardy-Weinberg expected heterozygosity (H(e) = colony 0.025 +/- 0.02 versus field 0.085 +/- 0.01). Three of the 11 loci (Acoh, Pgd, and Pgm) from the Vero Beach field samples showed bimodal patterns in their frequencies of the most common allele during peak density of the population. The low value of F(st) of 0.058 indicated minimum population substructuring among the temporal samples. Genetic variability values between geographic samples from the Florida panhandle and south Florida were not significant. Gene flow estimates based on F(ST), = 0.05, indicating low levels of gene flow among the geographic samples of Cx. p. quinquefasciatus. The average Nei's and modified Rogers' genetic distances among the six populations were 0.005 +/- 0.001 and 0.077 +/- 0.007, respectively. The cluster analysis did not suggest geographic clustering. The analysis of the "complex" gene enzymes in both temporal and geographic samples of Cx. p. quinquefasciatus from Florida showed the presence of two highly amplified esterases (Estbeta1 and Estalpha2\Estbeta2), indicating resistance to organophosphate insecticides and highly amplified Aldox enzyme (an enzyme that indicates resistance to at least one insecticide and a herbicide). Comparison of our results with previous studies on Cx. p. quinquefasciatus populations in the United States indicates that the genetic characteristics of the Florida populations of Cx. p. quinquefasciatus are very similar to populations from areas where ecological conditions are very different.

UI	MeSH Term	Description	Entries
D010058	Oviposition	The process of laying or shedding fully developed eggs (OVA) from the female body. The term is usually used for certain INSECTS or FISHES with an organ called ovipositor where eggs are stored or deposited before expulsion from the body.	Larviposition,Larvipositions,Ovipositions
D011110	Polymorphism, Genetic	The regular and simultaneous occurrence in a single interbreeding population of two or more discontinuous genotypes. The concept includes differences in genotypes ranging in size from a single nucleotide site (POLYMORPHISM, SINGLE NUCLEOTIDE) to large nucleotide sequences visible at a chromosomal level.	Gene Polymorphism,Genetic Polymorphism,Polymorphism (Genetics),Genetic Polymorphisms,Gene Polymorphisms,Polymorphism, Gene,Polymorphisms (Genetics),Polymorphisms, Gene,Polymorphisms, Genetic
D002874	Chromosome Mapping	Any method used for determining the location of and relative distances between genes on a chromosome.	Gene Mapping,Linkage Mapping,Genome Mapping,Chromosome Mappings,Gene Mappings,Genome Mappings,Linkage Mappings,Mapping, Chromosome,Mapping, Gene,Mapping, Genome,Mapping, Linkage,Mappings, Chromosome,Mappings, Gene,Mappings, Genome,Mappings, Linkage
D003465	Culex	A genus of mosquitoes (CULICIDAE) commonly found in tropical regions. Species of this genus are vectors for ST. LOUIS ENCEPHALITIS as well as many other diseases of man and domestic and wild animals.	Culices
D004777	Environment	The external elements and conditions which surround, influence, and affect the life and development of an organism or population.	Environmental Impact,Environmental Impacts,Impact, Environmental,Impacts, Environmental,Environments
D004798	Enzymes	Biological molecules that possess catalytic activity. They may occur naturally or be synthetically created. Enzymes are usually proteins, however CATALYTIC RNA and CATALYTIC DNA molecules have also been identified.	Biocatalyst,Enzyme,Biocatalysts
D005260	Female		Females
D005431	Florida	State bounded on east by the Atlantic Ocean, on the south by the Gulf of Mexico, on the west by Alabama and on the north by Alabama and Georgia.
D005843	Geography	The science dealing with the earth and its life, especially the description of land, sea, and air and the distribution of plant and animal life, including humanity and human industries with reference to the mutual relations of these elements. (From Webster, 3d ed)	Factor, Geographic,Factors, Geographic,Geographic Factor,Geographic Factors,Geography, Human,Human Geography
D000483	Alleles	Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.	Allelomorphs,Allele,Allelomorph