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Population genetics of anthelmintic resistance in parasitic nematodes

Published online by Cambridge University Press:  03 July 2007

J. S. GILLEARD  and
R. N. BEECH
J. S. GILLEARD*
Affiliation:
Division of Infection and Immunity, Institute of Comparative Medicine, Faculty of Veterinary Medicine, University of Glasgow, Bearsden Road, Glasgow, UKG61 1QH
R. N. BEECH
Affiliation:
Institute of Parasitology, Macdonald College, McGill University, 21,111 Lakeshore Road, Ste Anne de Bellevue, Quebec, CanadaH9X 3V9
*
*Corresponding author. Tel: (141) 330 5604. Fax: (141) 330 5603. E-mail: j.gilleard@vet.gla.ac.uk
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Summary

A key aim of anthelmintic resistance research is to identify molecular markers that could form the basis of sensitive and accurate diagnostic tests. These would provide powerful tools to study the origin and spread of anthelmintic resistance in the field and to monitor strategies aimed at preventing and managing resistance. Molecular markers could also form the basis of routine diagnostic tests for use in surveillance and clinical veterinary practice. Much of the research conducted to date has focused on the investigation of possible associations of particular candidate genes with the resistance phenotype. In the future, as full parasite genome sequences become available, there will be an opportunity to apply genome-wide approaches to identify the genetic loci that underlie anthelmintic resistance. Both the interpretation of candidate gene studies and the application of genome-wide approaches require a good understanding of the genetics and population biology of the relevant parasites as well as knowledge of how resistance mutations arise and are selected in populations. Unfortunately, much of this information is lacking for parasitic nematodes. This review deals with a number of aspects of genetics and population biology that are pertinent to these issues. We discuss the possible origins of resistance mutations and the likely effects of subsequent selection on the genetic variation at the resistance-conferring locus. We also review some of the experimental approaches that have been used to test associations between candidate genes and anthelmintic resistance phenotypes and highlight implications for future genome-wide studies.

Keywords

Anthelmintic resistanceHaemonchus contortusgenetic linkageSNPgenetic marker
Type
Research Article
Information
Parasitology , Volume 134 , Special Issue 8: MARKERS FOR ANTHELMINTIC RESISTANCE , August 2007 , pp. 1133 - 1147
Copyright
Copyright © Cambridge University Press 2007

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