Genetic Diversity of Hard Ticks (Acari: Ixodidae) in the South and East Regions of Kazakhstan and Northwestern China

Abstract

To date, there is no report on the genetic diversity of ticks in these regions. A total of 370 representative ticks from the south and east regions of Kazakhstan (SERK) and Xinjiang Uygur Autonomous Region (XUAR) were selected for molecular comparison. A fragment of the mitochondrial cytochrome c oxidase subunit I (cox1) gene, ranging from 631 bp to 889 bp, was used to analyze genetic diversity among these ticks. Phylogenetic analyses indicated 7 tick species including Hyalomma asiaticum, Hyalomma detritum, Hyalomma anatolicum, Dermacentor marginatus, Rhipicephalus sanguineus, Rhipicephalus turanicus and Haemaphysalis erinacei from the SERK clustered together with conspecific ticks from the XUAR. The network diagram of haplotypes showed that i) Hy. asiaticum from Almaty and Kyzylorda Oblasts together with that from Yuli County of XUAR constituted haplogroup H-2, and the lineage from Chimkent City of South Kazakhstan was newly evolved; and ii) the R. turanicus ticks sampled in Israel, Almaty, South Kazakhstan, Usu City, Ulugqat and Baicheng Counties of XUAR were derivated from an old lineage in Alataw City of XUAR. These findings indicate that: i) Hy. asiaticum, R. turanicus and Ha. erinacei shared genetic similarities between the SERK and XUAR; and ii) Hy. marginatum and D. reticulatus show differences in their evolution.

Keywords: Genetic diversity; Kazakhstan; hard tick; northwestern China.

Fig. 1

Maximum-likelihood (ML; 1,000 bootstrap replicates) phylogenetic tree of the cox1 constructed with MEGA 7.0 software, using the sequences of tick species from SERK (▲) and XUAR (△) in this study and the sequences available in the GenBank. The scale bar represented the inferred substitutions per nucleotide site. A network diagram of Hyalomma asiaticum in the haplotypes A network diagram of Rhipicephalus turanicus in the haplotypes

Fig. 2

Network diagrams of Hyalomma asiaticum and Rhipicephalus turanicus showing the haplotypes in the SERK and XUAR based on the mitochondrial cox1 gene.