The malaria parasite, Plasmodium falciparum, has developed resistance to most of the major classes of antimalarial drugs currently in use, which severly hampers our ability to control this disease. Knowledge of the genetic basis of resistance would provide insights into mode of action of antimalarial drugs, as well as providing a basis for development of novel compounds and redesign of existing drugs. We propose to exploit the dense microsatellite map and the emerging genome sequence data frm P. falciparum together with recent advances in statistical genetics to locate genes underlying drug resistance. Our approach will involve both phenotypic and genotypic characterization of field collected parasites. We will measure in vitro susceptibility to 4 important antimalarial compounds-mefloquine, quinine, artemisinin and chloroquine in malaria parasites obtained from a site on the Thai-Burmese border. We will then genotype these parasites for 200 microsatellite markers distributed at 5-10 cM intervals across the parasite genome. To locate genomic regions containing quantitative trait loci for drug resistance we will use two-stage strategy. First we will use variance component linkage methods in which we use genetic marker data to infer kinship relationships between parasites. We will then fine-scale map regions of the genome containing quantitative trait loci for drug resistance, by inspecting linkage disequilibrium between marker loci and genes underlying resistance. Candidate genes will be identified using sequence data emerging from the malaria genome project.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI048071-03
Application #
6534285
Study Section
Special Emphasis Panel (ZRG1-TMP (01))
Program Officer
Gottlieb, Michael
Project Start
2000-09-01
Project End
2005-05-31
Budget Start
2002-09-01
Budget End
2003-05-31
Support Year
3
Fiscal Year
2002
Total Cost
$429,779
Indirect Cost
Name
Southwest Foundation for Biomedical Research
Department
Type
DUNS #
City
San Antonio
State
TX
Country
United States
Zip Code
78245
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Simpson, Julie A; Jamsen, Kris M; Anderson, Tim J C et al. (2013) Nonlinear mixed-effects modelling of in vitro drug susceptibility and molecular correlates of multidrug resistant Plasmodium falciparum. PLoS One 8:e69505
Phyo, Aung Pyae; Nkhoma, Standwell; Stepniewska, Kasia et al. (2012) Emergence of artemisinin-resistant malaria on the western border of Thailand: a longitudinal study. Lancet 379:1960-6
Nkhoma, Standwell C; Nair, Shalini; Cheeseman, Ian H et al. (2012) Close kinship within multiple-genotype malaria parasite infections. Proc Biol Sci 279:2589-98
Cheeseman, Ian H; Miller, Becky A; Nair, Shalini et al. (2012) A major genome region underlying artemisinin resistance in malaria. Science 336:79-82
Anderson, Tim; Nkhoma, Standwell; Ecker, Andrea et al. (2011) How can we identify parasite genes that underlie antimalarial drug resistance? Pharmacogenomics 12:59-85
Nair, Shalini; Nkhoma, Standwell; Nosten, Francois et al. (2010) Genetic changes during laboratory propagation: copy number At the reticulocyte-binding protein 1 locus of Plasmodium falciparum. Mol Biochem Parasitol 172:145-8
Anderson, Tim J C; Nair, Shalini; Nkhoma, Standwell et al. (2010) High heritability of malaria parasite clearance rate indicates a genetic basis for artemisinin resistance in western Cambodia. J Infect Dis 201:1326-30
Anderson, Tim J C; Williams, Jeff T; Nair, Shalini et al. (2010) Inferred relatedness and heritability in malaria parasites. Proc Biol Sci 277:2531-40
Anderson, Tim J C; Patel, Jigar; Ferdig, Michael T (2009) Gene copy number and malaria biology. Trends Parasitol 25:336-43

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