title: DNA barcodes identify medically important tick species in Canada.
abstract: Medically important ticks (Acari: Ixodidae) are often difficult to identify morphologically. A standardized, molecular approach using a 658 base pair DNA barcode sequence (from the 5' region of the mitochondrial cytochrome c oxidase subunit I gene) was evaluated for its effectiveness in discriminating ticks in North America, with an emphasis on Canadian ticks. DNA barcodes were generated for 96 of 154 specimens representing 26 ixodid species. A genetic cluster analysis was performed on the barcode sequences, which separated specimens into haplogroups closely corresponding with morphologically identified species. The tree topology was further supported by a BIN analysis. COI sequences generated were found to have a mean maximum intraspecific divergence of 1.59% and a mean nearest neighbour divergence of 12.8%, indicating a significant "barcode gap". This study also revealed possible cryptic diversity among specimens morphologically identified as Ixodes soricis and Ixodes texanus. A PCR-based test for Borrelia burgdorferi determined that 18.1% of Lyme-competent ticks in this study were positive. This study is also the first to record a B. burgdorferi-positive exoskeleton. In conclusion, DNA barcoding is a powerful tool that clinicians can use to determine the identification of tick specimens which can help them to suggest whether an attached tick is a potential health risk.
authors.affiliation: Department of Integrative Biology, Biodiversity Institute of Ontario, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada.|Department of Integrative Biology, Biodiversity Institute of Ontario, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada.
authors.forename: Danielle A
authors.initials: DA
authors.lastname: Ondrejicka
authors.affiliation: Department of Integrative Biology, Biodiversity Institute of Ontario, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada.|Department of Integrative Biology, Biodiversity Institute of Ontario, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada.
authors.forename: Kevin C
authors.initials: KC
authors.lastname: Morey
authors.affiliation: Department of Integrative Biology, Biodiversity Institute of Ontario, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada.|Department of Integrative Biology, Biodiversity Institute of Ontario, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada.
authors.forename: Robert H
authors.initials: RH
authors.lastname: Hanner
mesh_terms: D000818:Animals; D044822:Biodiversity; D025065:Borrelia burgdorferi / Q000235:genetics; D002170:Canada; D058893:DNA Barcoding, Taxonomic; D003576:Electron Transport Complex IV / Q000235:genetics; D050259:Genes, Mitochondrial; D005843:Geography; D006801:Humans; D018884:Ixodes / Q000145:classification / Q000235:genetics / Q000382:microbiology; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D013987:Ticks / Q000145:classification* / Q000235:genetics* / Q000382:microbiology
chemical_list: D003576:Electron Transport Complex IV
keywords: Borrelia burgdorferi; COI; DNA barcoding; codage à barres de l’ADN; cryptic diversity; diversité cryptique; identification des tiques; tick identification