Characterisation of taeniid cestode species by PCR-RFLP of ITS2 ribosomal DNA.

Seven species of taeniid cestode (Echinococcus granulosus. E. multilocularis, Taenia hydatigena, T. ovis, T. pisiformis, T. multiceps and T. serialis) were characterised using a polymerase chain reaction-based restriction fragment length polymorphism technique (PCR-RFLP). The second internal transcribed spacer of ribosomal DNA (ITS2) was amplified from various geographical isolates of each of the seven species, digested separately with four restriction endonucleases and the fragments were separated by conventional agarose gel electrophoresis. PCR-RFLP produced characteristic patterns for each taeniid species examined. No variation in RFLP patterns was observed among different isolates of E. multilocularis and the species of Taenia, but distinct intraspecific variation was detected in E. granulosus. The present study indicates the usefulness of the PCR-RFLP of ITS2 for systematic, epidemiological and diagnostic purposes.