Mosquitoes belonging to the genus Anopheles are the only vectors of human malaria. Anopheles gibbinsi has been linked to malaria transmission in Kenya, with recent collections in Zambia reporting the mosquito species exhibiting zoophilic and exophilic behavioral patterns with occasional contact with humans. Given the paucity of genetic data, and challenges to identification and molecular taxonomy of the mosquitoes belonging to the Anopheles genus; we report the first complete mitochondrial genome of An. gibbinsi using a genome skimming approach. An Illumina Novaseq 6000 platform was used for sequencing, the length of the mitochondrial genome was 15401 bp, with 78.5% AT content comprised of 37 genes. Phylogenetic analysis by maximum likelihood using concatenation of the 13 protein coding genes demonstrated that An. marshallii was the closest relative based on existing sequence data. This study demonstrates that the skimming approach is an inexpensive and efficient approach for mosquito species identification and concurrent taxonomic rectification, which may be a useful alternative for generating reference sequence data for evolutionary studies among the Culicidae.
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Mitogenomes of mosquito species of Harris County in Texas
Harris County, Texas, remains at continuous risk to mosquito-borne diseases due to its geographic landscape and abundance of medically important mosquito vectors. Targeted mitigation of these mosquitoes requires accurate identification of these mosquitoes taxa. Currently, there is a paucity of genetic information to inform molecular identification and phylogenetic relationships beyond well-studied mosquito species. Here we utilized a genome skimming approach using shallow shot gun sequencing to generate data and assemble the mitochondrial genomes of 37 mosquito species collected in Harris County, Texas. This report includes the complete mitochondrial genome for 25 newly sequenced species spanning 10 genera; the genomes were consistent with reference genomes in the GenBank database having 37 genes (13 protein-coding, 2 rRNA and 22 tRNA), and average AT content of 78.74%. Bayesian and maximum likelihood tree topologies using just the easily aligned 13 concatenated protein coding genes confirmed phylogenetic placement of species for Aedes, Anopheles and Culex genera clustering in single clades as expected. Furthermore, this approach provided more robust phylogenetic placement/identity of study taxa when compared to the use of the traditional cytochrome oxidase I partial gene barcode sequence for molecular identification. This study demonstrates the utility of genome skimming as a cost-effective alternative approach to generate reference sequences for the validation of mosquito identification and taxonomic rectification, knowledge necessary for guiding targeted vector interventions.
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- Award ID(s):
- 2134862
- PAR ID:
- 10662409
- Publisher / Repository:
- Scientific Reports
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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