Keywords: DNA chips; malaria; drug resistance
This project aims at evaluating a newly developed DNA micro array for drug resistance monitoring in affected areas. Results will allow the dynamics of drug resistance to be captured and to forecast its development by establishing a community-based genetic resistance index, providing tools for rational and evidence-based decisions on the optimal use of drugs. The relationship between in vivo drug sensitivity and in vitro susceptibility to several anti-malarials, and the prevalence of multiple SNPs providing correlates for clinical resistance will be assessed. Sequencing will identify additional informative codons.
The genetic diversity of malaria parasites is a major obstacle in the development of rational control strategies against this poverty related disease. Increase of health threatening drug resistance must be monitored and prevented to protect introduced drugs.
The aims of this project are:
During the initial phase of the project, a prototype SNP analysis chip will be developed into an applicable tool. This includes the establishment of robust SOPs, inclusion of and verification of newly identified SNP sites, as well as an evaluation against currently used SNP analysis methods. In parallel, health centre and community surveys in the respective field sites will be set up by field teams. Furthermore, studies on resistance markers for artemisinin derivatives and large-scale sequencing on known resistance markers will be conducted from the beginning of the project onwards. As soon as health centre and community surveys have been set up, in vitro drug sensitivity studies will be performed. Upon conducting the first community surveys, samples will be prepared according to standard methods for molecular genotyping and analysed using the produced SNP micro array, but will also be tested against RFLP-based SNP analysis. Also during this process, technology transfer will take place in two selected field sites with appropriate infrastructure. Optimisation and the addition of new marker SNPs to the micro array system will be ongoing throughout the process. Quality control and further system validation will be performed by repeating approximately 10% of samples for SNP micro array analysis, but also for comparative analysis using classical SNP analysis methods.
During the analysis process, software will be developed (together with the bioinformatics units of STI, IP, and CMDT). All data will be entered electronically into a database and upon first closure (after the first round of surveys), the proposed genetic resistance index will be calculated and a predictive model will be established and tested.
Results should allow forecasting of the development of malarial drug resistance through the establishment of a community-based genetic resistance index, providing tools for rational and evidence-based decisions on optimal use of antimalarial drugs.
Virgílio E. do Rosário
Centro de Malária e Outras Doenças Tropicais
Instituto de Higiene e Medicina Tropical
Rua da Junqueira, 96
Tel: +351-1-362 24 58
Fax: +351-1-362 24 58
|Official Address||Other Information|
|2||Odile Mercereau-Puijalon||Institut Pasteur
25 rue du ROUX
FR-75724 Paris Cedex 15
|3||Hans-Peter Beck and Ingrid Felger||Swiss Tropical Institute
|4||Anders Bjorkman||Karolinska Institutet, Department of Medicine
Unit of Infectious Diseases Karolinska Hospital
SE-171 77 Stockolm