title: Isothermal Diagnostic Assays for Monitoring Single Nucleotide Polymorphisms in Necator americanus Associated with Benzimidazole Drug Resistance.
abstract: Soil-transmitted helminths (STHs) are the most prevalent intestinal helminths of humans, and a major cause of morbidity in tropical and subtropical countries. The benzimidazole (BZ) drugs albendazole (ABZ) and mebendazole (MBZ) are used for treatment of human STH infections and this use is increasing dramatically with massive drug donations. Frequent and prolonged use of these drugs could lead to the emergence of anthelmintic resistance as has occurred in nematodes of livestock. Previous molecular assays for putative resistance mutations have been based mainly on PCR amplification and sequencing. However, these techniques are complicated and time consuming and not suitable for resource-constrained situations. A simple, rapid and sensitive genotyping method is required to monitor for possible developing resistance to BZ drugs.
  
  
  
  To address this problem, single nucleotide polymorphism (SNP) detection assays were developed based on the Smart amplification method (SmartAmp2) to target codons 167, 198, and 200 in the β-tubulin isotype 1 gene for the hookworm Necator americanus.
  
  
  
  Diagnostic assays were developed and applied to analyze hookworm samples by both SmartAmp2 and conventional sequencing methods and the results showed high concordance. Additionally, fecal samples spiked with N. americanus larvae were assessed and the results showed that the Aac polymerase used has high tolerance to inhibitors in fecal samples.
  
  
  
  The N. americanus SmartAmp2 SNP detection assay is a new genotyping tool that is rapid, sensitive, highly specific and efficient with the potential to be used as a field tool for monitoring SNPs associated with BZ resistance. However, further validation on large numbers of field samples is required.
authors.affiliation: Institute of Parasitology, Macdonald College, McGill University, Ste Anne de Bellevue, QC, Canada.
authors.forename: Nour
authors.initials: N
authors.lastname: Rashwan
authors.affiliation: Institute of Parasitology, Macdonald College, McGill University, Ste Anne de Bellevue, QC, Canada.
authors.forename: Catherine
authors.initials: C
authors.lastname: Bourguinat
authors.affiliation: Institute of Parasitology, Macdonald College, McGill University, Ste Anne de Bellevue, QC, Canada.
authors.forename: Kathy
authors.initials: K
authors.lastname: Keller
authors.affiliation: Department of Parasitology, Faculty of Medicine, University of Kelaniya, Ragama, Sri Lanka.
authors.forename: Nipul Kithsiri
authors.initials: NK
authors.lastname: Gunawardena
authors.affiliation: Department of Parasitology, Faculty of Medicine, University of Kelaniya, Ragama, Sri Lanka.
authors.forename: Nilanthi
authors.initials: N
authors.lastname: de Silva
authors.affiliation: Institute of Parasitology, Macdonald College, McGill University, Ste Anne de Bellevue, QC, Canada.
authors.forename: Roger
authors.initials: R
authors.lastname: Prichard
mesh_terms: D000818:Animals; D000969:Antinematodal Agents / Q000494:pharmacology*; D001562:Benzimidazoles / Q000378:metabolism / Q000494:pharmacology*; D004351:Drug Resistance / Q000235:genetics*; D060005:Genotyping Techniques; D006801:Humans; D017221:Necator americanus / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D020641:Polymorphism, Single Nucleotide; D012680:Sensitivity and Specificity; D013696:Temperature; D014404:Tubulin / Q000235:genetics
chemical_list: D000969:Antinematodal Agents; D001562:Benzimidazoles; D014404:Tubulin; C031000:benzimidazole