Taenia spp.: 18S rDNA microsatellites for molecular systematic diagnosis

Abstract

The 18S rDNA gene of adult worms of Taenia parva found in Genetta genetta in the Iberian Peninsula and larval stages of T. pisiformis from the wild rabbit (Oryctolagus cuniculus) in Tenerife (Canary Islands) were amplified and sequenced. The sequences of the 18S rDNA gene of T. parva (1768 bp) and T. pisiformis (1760 bp) are reported for the first time (GenBank accession nos. AJ555167-AJ555168 and AJ555169-AJ555170, respectively). In 168 alignment positions microsatellites in the 18S rDNA of both taxa were detected for the first time (TGC in T. parva and TGCT in T. pisiformis) and differences in their sequences with different repetition numbers were observed. The use of nucleotide sequences of this gene in the resolution of systematic problems in cestodes is discussed with reference to the systematic status of Taenia spp. and mainly in human taeniids such as T. solium, T. saginata, and Asian human isolates of Taenia.

Sequence variability in two mitochondrial DNA regions and internal transcribed spacer among three cestodes infecting animals and humans from China

“…The intra-specific variation in the length of the S. erinaceieuropaei, T. multiceps and T. hydatigena sequences was due to the deletion/ insertion of a three-nucleotide (CTG)n repeat extending from positions 60 to 75 in the ITS-1, and a two-nucleotide (GT)n repeat extending from positions 280 to 290 in the ITS-1, respectively. The deletion/insertion of a (TGG or CGG)n repeat extending from positions 882 to 888 in the ITS-2, and a six-dinucleotide (TGGCGG)n repeat extending from positions 820 to 840 in the ITS-2, respectively, was consistent with previous reports of the (SSR) polymorphisms for parasitic cestodes (van Herwerden et al, 2000;Luo et al, 2002;Foronda et al, 2005). These microsatellite sequences have been widely used as genetic markers for the study of population genetic structure, although their actual function is not quite clear (Luo et al, 2002).…”

Schistocephalus cotti n. sp. (Cestoda: Pseudophyllidea) plerocercoids from bullheads Cottus gobio L. in an Arctic river in Finland, with a key to the plerocercoids of the Palaearctic species of the genus

“…Microsatellites offer great promise for biology (Ellegren, 2004), but relatively little is known about them in parasitic helminths (Bretagne, Assouline, Vidaud, Houin, & Vidaud, 1996;Foronda, Casanova, Martinez, & Feliu, 2005), although molecular markers have considerable potential for investigating ecological, genetic and microevolutionary processes (Criscione, Poulin, & Blouin, 2005;Rauch, Kalbe, & Reusch, 2005). Foronda et al (2005) used the 18S rDNA gene to differentiate two species of Taenia L., 1758.…”

“…Foronda et al (2005) used the 18S rDNA gene to differentiate two species of Taenia L., 1758. In our investigation, the positive microsatellite comparisons with those of Binz et al (2000) and Lü scher (2002) for plerocercoids from G. aculeatus f. leiurus contrast with the negative results obtained with plerocercoids of C. gobio from the River Utsjoki and also verify their distinctness.…”

Multiplex PCR identification of Taenia spp. in rodents and carnivores

“…and Sarcocystis spp. in pigs and cattle (Gonzalez et al 2006), while another PCR targeting the 18S ribosomal DNA gene (18S rDNA) discriminated between Taenia pisiformis and Taenia parva (Foronda et al 2005). The PCR system of Trachsel et al (2007) differentiated between zoonotic Echinococcus spp.…”