Leignel V, Humbert J F, Elard L
INRA, Station de Pathologie Aviaire et de Parasitologie, Nouzilly, France.
J Parasitol. 1997 Aug;83(4):606-11.
Four species of lungworms of the Metastrongylus genus are found sympatrically in the lungs of the wild boars (Sus scrofa L.) on the Chambord game reserve (France): Metastrongylus asymmetricus, M. confusus, M. pudendotectus, and M. salmi. These species are difficult to identify using morphological characters alone, and epidemiological evidence raises doubt about the existence of 4 distinct species. Two molecular approaches (sequencing of ribosomal DNA Internal Transcribed Spacer 2 [ITS 2] and Random Amplified Polymorphic DNA assay [RAPD]) were used to evaluate the genetic similarities between the 4 taxa. The ITS 2 sequences of M. salmi and M. confusus were identical, whereas the sequences of the other species were distinct. On the other hand, RAPD analysis indicated unambiguously that the 4 species are genetically different. These results reveal the limitation of using only 1 molecular approach for taxonomic studies and indicate the need to examine different regions (ribosomal, mitochondrial DNA) in the genome of a species in complement with morphological and epidemiological data.
在尚博尔狩猎保护区（法国）的野猪（Sus scrofa L.）肺部同时发现了后圆属的四种肺线虫：不对称后圆线虫、混淆后圆线虫、阴户后圆线虫和萨尔米后圆线虫。仅使用形态学特征很难鉴定这些物种，并且流行病学证据对这4个不同物种的存在提出了质疑。采用两种分子方法（核糖体DNA内转录间隔区2 [ITS 2] 测序和随机扩增多态性DNA分析 [RAPD]）来评估这4个分类单元之间的遗传相似性。萨尔米后圆线虫和混淆后圆线虫的ITS 2序列相同，而其他物种的序列则不同。另一方面，RAPD分析明确表明这4个物种在遗传上是不同的。这些结果揭示了仅使用1种分子方法进行分类学研究的局限性，并表明需要结合形态学和流行病学数据，对物种基因组中的不同区域（核糖体、线粒体DNA）进行研究。
