This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Keen, J.
Right arrow Articles by Kain, K. C.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Keen, J.
Right arrow Articles by Kain, K. C.

 Previous Article  |  Next Article 

Journal of Clinical Microbiology, September 2007, p. 2889-2893, Vol. 45, No. 9
0095-1137/07/$08.00+0     doi:10.1128/JCM.02291-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Real-Time PCR Assay for Rapid Detection and Analysis of PfCRT Haplotypes of Chloroquine-Resistant Plasmodium falciparum Isolates from India{triangledown}

Jessica Keen,1,{dagger} Gabriella A. Farcas,1,{dagger} Kathleen Zhong,2 Seychelle Yohanna,2 Michael W. Dunne,3 and Kevin C. Kain1,2*

Institute of Medical Science, Faculty of Medicine,1 McLaughlin-Rotman Centre, McLaughlin Centre for Molecular Medicine, University of Toronto, Toronto, Canada,2 Pfizer Global Research and Development, New London, Connecticut3

Received 10 November 2006/ Returned for modification 28 March 2007/ Accepted 20 May 2007

Chloroquine-resistant Plasmodium falciparum (CRPF) malaria isolates in Southeast Asia and sub-Saharan Africa share the same Plasmodium falciparum chloroquine resistance transporter (PfCRT) haplotype (CVIET; amino acids 72 to 76). It is believed that CRPF malaria emerged in Southeast Asia and spread to sub-Saharan Africa via the Indian subcontinent. Based on this assumption, we hypothesized that CRPF isolates in India should possess the same drug resistance haplotype (PfCRT haplotype CVIET) as P. falciparum isolates in Southeast Asia and Africa and that the prevalence of CRPF may be higher and more widespread in India than appreciated. To test this postulate, we utilized a standardized real-time PCR assay to assess the prevalence and distribution of PfCRT haplotypes in P. falciparum isolates (n = 406) collected from Western, Central, and Eastern states in India and compared them to isolates from South America and Africa. Based on the proportion of isolates possessing the molecular marker K76T, the prevalence of chloroquine resistance was high in all five regions of India studied (91%), as well as in Uganda (98%) and Suriname (100%). All isolates from Suriname contained the chloroquine-resistant SVMNT haplotype typical of South American isolates, and 98% of isolates from Uganda possessed the chloroquine-resistant CVIET haplotype characteristic of Southeast Asian/African strains. However, of 246 P. falciparum isolates from across India that contained the molecular marker for chloroquine resistance, 81% contained the SVMNT haplotype. In conclusion, the prevalence of CRPF malaria was high in geographically dispersed regions of India, and the primary haplotype observed, SVMNT, did not support a presumed geographic spread from contiguous Southeast Asia.


* Corresponding author. Mailing address: Tropical Disease Unit, Eaton North 13-214, Toronto General Hospital, 200 Elizabeth Street, Toronto, Ontario M5G 2C4, Canada. Phone: (416) 340-3535. Fax: (416) 595-5826. E-mail: kevin.kain{at}uhn.on.ca

{triangledown} Published ahead of print on 3 July 2007.

{dagger} These authors contributed equally to this work.


Journal of Clinical Microbiology, September 2007, p. 2889-2893, Vol. 45, No. 9
0095-1137/07/$08.00+0     doi:10.1128/JCM.02291-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.




This article has been cited by other articles:

  • Zakeri, S., Afsharpad, M., Kazemzadeh, T., Mehdizadeh, K., Shabani, A., Djadid, N. D. (2008). Association of pfcrt But Not pfmdr1 Alleles with Chloroquine Resistance in Iranian Isolates of Plasmodium falciparum. Am J Trop Med Hyg 78: 633-640 [Abstract] [Full Text]