Determination of genomic DNA sequences for beta-tubulin isotype 1 from multiple species of cyathostomin and detection of resistance alleles in third-stage larvae from horses with naturally acquired infections.

ABSTRACT:

Background

Genetic resistance against benzimidazole (BZ) anthelmintics is widespread in cyathostomins, the commonest group of intestinal parasitic nematodes of horses. Studies of BZ-resistant nematodes of sheep, particularly Haemonchus contortus, have indicated that an anthelmintic resistance-conferring T/A polymorphism, encoding an F (phenylalanine) to Y (tyrosine) substitution, in beta-tubulin isotype 1 is present at two loci, codons 167 and 200 (F167Y, F200Y). Recent studies using complementary (c) DNA derived from BZ-susceptible and -resistant cyathostomins identified statistical differences in the frequency of the BZ-resistant A allele at these loci. However, the lack of high-throughput genomic DNA-based detection of polymorphisms limits the study of eggs or larvae from field

SUBMITTER: Lake SL 

PROVIDER: S-EPMC2751842 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature