Traversa Donato, Costanzo Francesca, Iorio Raffaella, Aroch Itamar, Lavy Eran
Department of Comparative Biomedical Sciences, Faculty of Veterinary Medicine, University of Teramo, Piazza Aldo Moro 45, 64100 Teramo, Italy.
Vet Parasitol. 2007 May 31;146(3-4):263-70. doi: 10.1016/j.vetpar.2007.03.015. Epub 2007 Apr 10.
Canine spirocercosis is a life-threatening parasitosis caused by Spirocerca lupi (Nematoda, Spirurida) that is presently emerging in several countries. This study characterised an informative region within the mitochondrial (mtDNA) gene encoding for the cytochrome c oxidase subunit 1 (cox1) of S. lupi by Polymerase Chain Reaction (PCR)-coupled sequencing. Specimens from five different countries in Europe, Asia and Africa were examined and two different sequence variants of cox1 (i.e. haplotypes) were determined, displaying nucleotidic variation at 6 of 689 positions. All of these positions were invariable among all the parasite individuals from Europe (haplotype 1) and among the African and Asian individuals (haplotype 2), but differed between Europe and Asia/Africa. The S. lupi cox1 sequences were consistent with those of other common Spirurida previously reported at both nucleotidic and phylogenetic levels. This study provides molecular information essential for identification of the nematode, irrespective of its life cycle stage. Crucial implications for the specific molecular diagnosis of clinical spirocercosis and investigation of the evolution, population genetics, ecology and epidemiology of S. lupi are discussed.
犬食管虫病是由狼旋尾线虫（线虫纲，旋尾目）引起的一种危及生命的寄生虫病，目前在多个国家出现。本研究通过聚合酶链反应（PCR）结合测序对狼旋尾线虫线粒体（mtDNA）基因中编码细胞色素c氧化酶亚基1（cox1）的一个信息区域进行了特征分析。对来自欧洲、亚洲和非洲五个不同国家的样本进行了检测，确定了cox1的两种不同序列变体（即单倍型），在689个位置中的6个位置显示出核苷酸变异。在来自欧洲的所有寄生虫个体（单倍型1）以及非洲和亚洲个体（单倍型2）中，所有这些位置都是不变的，但欧洲与亚洲/非洲之间存在差异。狼旋尾线虫的cox1序列在核苷酸和系统发育水平上均与先前报道的其他常见旋尾目一致。本研究提供了识别该线虫所必需的分子信息，无论其处于生命周期的哪个阶段。讨论了对临床食管虫病的特异性分子诊断以及狼旋尾线虫的进化、群体遗传学、生态学和流行病学研究的关键意义。
