First identification of the F200Y SNP in the β-tubulin gene linked to benzimidazole resistance in Ancylostoma caninum.

Single nucleotide polymorphisms (SNPs) in the β-tubulin isotype 1 gene in codons 167, 198 and 200 have been associated with benzimidazole resistance in some nematodes, although no polymorphisms in this gene have been described in the hookworm Ancylostoma caninum to date. This study aimed to screen for SNPs in the β-tubulin isotype 1 gene at codons 198 and 200 associated with benzimidazole resistance in A. caninum worms recovered from naturally infected dogs from two Brazilian states (Minas Gerais and Piauí). To perform this analysis, a molecular technique based on the amplification refractory mutation system (ARMS-PCR) was standardized. A total of 110 individual worms recovered from 9 dogs in Piauí and 124 individual worms recovered from 10 dogs in Minas Gerais were analyzed using this methodology. The presence of a SNP at position 200 was observed at a low frequency (0.8%), which was only detected in the worm population from Minas Gerais State. A total of 75 randomly selected samples were sequenced to validate this technique, and the presence of the SNP was confirmed. Furthermore, SNP at position 198 were evaluated by sequencing, and none were detected in this region. This is the first report of the presence of a SNP in the β-tubulin isotype 1 gene associated with benzimidazole resistance in an A. caninum population.