title: Genetic analysis of Toxocara cati (Nematoda: Ascarididae) from Guangdong province, subtropical China.
abstract: Toxocara cati (cat roundworm) is a common parasitic nematode that infects humans and other hosts, causing toxocariasis. Although its significance as a pathogen, the epidemiology, genetics and biology of T. cati remain poorly understand in China. In the present study, genetic variation in mitochondrial (mt) cytochrome c oxidase subunit 1 (cox1) gene and internal transcribed spacer (ITS) of rDNA region among T. cati in Guangdong province, subtropical China was examined. A portion of the cox1 (pcox1) and the complete ITS (ITS1 + 5.8S rDNA + ITS2) were amplified separately from individual worms by polymerase chain reaction (PCR) and amplicons were then subjected to sequencing from both directions. The length of the sequences of pcox1, ITS-1, and ITS-2 were 308 bp, 462 bp, and 335 bp, respectively. The intra-specific sequence variations within T. cati were 0-3.6% for pcox1, 0-2.4% for ITS-1, and 0-2.7% for ITS-2. However, the inter-specific sequence differences were significantly higher, being 8.6%, 10.7%, and 11.3% for pcox1, ITS-1, and ITS-2, respectively. Phylogenetic analyses based on the pcox1 sequences indicated that all the isolates in Guangdong province were in genus Toxocara, which confirmed that these parasites represent T. cati. The molecular approach employed provides a powerful tool for elucidating the epidemiology, genetics, and biology of zoonotic T. cati in China and elsewhere.
authors.affiliation: a College of Veterinary Medicine , South China Agricultural University , Guangzhou , Guangdong Province , PR China.|b Key Laboratory of Zoonosis Prevention and Control of Guangdong Province , Guangzhou , Guangdong Province , PR China.
authors.forename: Xi
authors.initials: X
authors.lastname: He
authors.affiliation: a College of Veterinary Medicine , South China Agricultural University , Guangzhou , Guangdong Province , PR China.|b Key Laboratory of Zoonosis Prevention and Control of Guangdong Province , Guangzhou , Guangdong Province , PR China.
authors.forename: Meng-Na
authors.initials: MN
authors.lastname: Lv
authors.affiliation: c College of Veterinary Medicine , Hunan Agricultural University , Changsha , Hunan Province , PR China.
authors.forename: Guo-Hua
authors.initials: GH
authors.lastname: Liu
authors.affiliation: a College of Veterinary Medicine , South China Agricultural University , Guangzhou , Guangdong Province , PR China.|b Key Laboratory of Zoonosis Prevention and Control of Guangdong Province , Guangzhou , Guangdong Province , PR China.
authors.forename: Rui-Qing
authors.initials: RQ
authors.lastname: Lin
mesh_terms: D000818:Animals; D002681:China; D018509:DNA, Helminth; D004272:DNA, Mitochondrial; D003576:Electron Transport Complex IV / Q000235:genetics; D050259:Genes, Mitochondrial; D014644:Genetic Variation; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D014119:Toxocara / Q000235:genetics* / Q000378:metabolism
chemical_list: D018509:DNA, Helminth; D004272:DNA, Mitochondrial; D003576:Electron Transport Complex IV
keywords: Genetic variation; Toxocara cati; internal transcribed spacer; mitochondrial DNA