Intraspecific and interspecific variation in the second internal transcribed spacer (ITS-2) sequence for Metastrongylus (Nematoda: Metastrongyloidea) detected by high resolution PCR-RFLP.

Metastrongylus species are important parasites of free-range pigs and wild boar, but little is known about the genetic make-up of natural populations. This study was undertaken to examine sequence variation in the internal transcribed spacer 2 of ribosomal DNA within and among three species of Metastrongylus using PCR-linked restriction fragment length polymorphism analysis. In contrast to many other species of bursate nematodes, significant intraspecific variation was detected in restriction fragment length polymorphism profiles among individual worms. In spite of this, it was possible to identify the three species by their distinctive restriction profiles. The findings suggest that the internal transcribed spacer 2 region should be useful for analysing population variation within Metastrongylus species.