02402naa a2200265 a 450000100080000000500110000800800410001902400520006010000220011224501220013426000090025652015820026565000150184765000250186265300350188765300280192265300080195070000170195870000200197570000220199570000210201770000190203870000240205777300550208121482762022-11-16       2022    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.1007/s00436-022-07682-62DOI1 aNICIURA, S. C. M.  aPolymorphisms in exon 11 of the mptl-1 gene and monepantel resistance in Haemonchus contortus.h[electronic resource]  c2022  aChemical treatments are the main strategy to control gastrointestinal nematodes in sheep, and the emergence of anthelmintic resistance, as consequence, results in control failures and leads to economic losses. Thus, molecular tests may constitute an excellent tool for the early detection of anthelmintic resistance-related mutations. Thus, a polymerase chain reaction (PCR)-based genotyping assay followed by polyacrylamide gel electrophoresis (PAGE) was developed to detect polymorphisms in exon 11 of the acetylcholine receptor monepantel-1 gene (mptl-1) that were previously associated with monepantel resistance through a genome-wide study in Haemonchus contortus. DNA samples recovered from individual and pooled third-stage larvae from two susceptible feld-derived isolates and fve (three in vivo-derived and two feld-derived) resistant populations were used. New polymorphisms, including a 6-bp deletion and a 3-bp insertion, were detected in resistant individuals. These indels, confrmed using sequencing of cloned PCR products, are predicted to result in amino acid changes in transmembrane domain 2 (TMD2) of the MPTL-1 protein. The two susceptible isolates showed only the presence of the wild-type allele (100%), whereas lower frequencies of the wild-type allele were detected in monepantel-resistant populations (11.1 to 66.7%). These fndings report new polymorphisms in the mptl-1 gene, validate the results obtained through genomic mapping for monepantel resistance, and provide a PCR-based assay to genotype indels located in exon 11 of mptl-1 in H. contortus.  aGenotyping  aHaemonchus Contortus  aAmino acetonitrile derivatives  aAnthelmintic resistance  aPCR1 aOKINO, C. H.1 aNUCCI, A. DA S.1 aMALAGO JUNIOR, W.1 aBENAVIDES, M. V.1 aESTEVES, S. N.1 aCHAGAS, A. C. de S.  tParasitology Researchgv. 121, p. 3581-3588, 2022.