Genomic variability within laboratory and wild isolates of the trichostrongyle mouse nematodeHeligmosomoides polygyrus

Abstract

AbstractPCR-RFLP techniques have been used to characterize wild and laboratory isolates of the trichostrongyle nematodeHeligmosomoides polygyrusfrom the wood mouseApodemus sylvaticusand the laboratory mouseMus musculusrespectively. Both isolates can be distinguished by eight endonuclease digestions of the ITS region of the rDNA repeat namely,AluI,DdeI,HpaII,HaeIII,HinfI,HhaI,PvuII andSalI. In two of the digests,HinfI andRsaI, a minor polymorphism was observed in the wild isolate ofH. polygyruswhich has been cultured in laboratory-bredA. sylvaticusfor several generations when compared withH. p. polygyrusfrom wildA. sylvaticus. A minor polymorphism was also identified in further wild isolates ofH. polygyruscollected fromA. sylvaticusin a field site in Egham, Surrey. However no evidence of polymorphism was observed in the laboratory isolate ofH. polygyrusfrom the CD1 strain ofM. musculusand the laboratory-bredA. sylvaticus. Reasons for this are discussed and further studies on the population genetics ofH. polygyrusare suggested.