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Published in: Malaria Journal 1/2014

Open Access 01-12-2014 | Research

Mutations in Plasmodium falciparum K13 propeller gene from Bangladesh (2009–2013)

Authors: Abu Naser Mohon, Mohammad Shafiul Alam, Abebe Genetu Bayih, Asongna Folefoc, Dea Shahinas, Rashidul Haque, Dylan R Pillai

Published in: Malaria Journal | Issue 1/2014

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Abstract

Background

Bangladesh is a malaria hypo-endemic country sharing borders with India and Myanmar. Artemisinin combination therapy (ACT) remains successful in Bangladesh. An increase of artemisinin-resistant malaria parasites on the Thai-Cambodia and Thai-Myanmar borders is worrisome. K13 propeller gene (PF3D7_1343700 or PF13_0238) mutations have been linked to both in vitro artemisinin resistance and in vivo slow parasite clearance rates. This group undertook to evaluate if mutations seen in Cambodia have emerged in Bangladesh where ACT use is now standard for a decade.

Methods

Samples were obtained from Plasmodium falciparum-infected malaria patients from Upazila health complexes (UHC) between 2009 and 2013 in seven endemic districts of Bangladesh. These districts included Khagrachari (Matiranga UHC), Rangamati (Rajasthali UHC), Cox’s Bazar (Ramu and Ukhia UHC), Bandarban (Lama UHC), Mymensingh (Haluaghat UHC), Netrokona (Durgapur and Kalmakanda UHC), and Moulvibazar (Sreemangal and Kamalganj UHC).

Results

Out of 296 microscopically positive P. falciparum samples, 271 (91.6%) were confirmed as mono-infections by both real-time PCR and nested PCR. The K13 propeller gene from 253 (93.4%) samples was sequenced bi-directionally. One non-synonymous mutation (A578S) was found in Bangladeshi clinical isolates. The A578S mutation was confirmed and lies adjacent to the C580Y mutation, the major mutation causing delayed parasite clearance in Cambodia. Based on computational modeling A578S should have a significant effect on tertiary structure of the protein.

Conclusion

The data suggest that P. falciparum in Bangladesh remains free of the C580Y mutation linked to delayed parasite clearance. However, the mutation A578S is present and based on structural analysis could affect K13 gene function. Further in vivo clinical studies are required to validate the effect of this mutation.
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Metadata
Title
Mutations in Plasmodium falciparum K13 propeller gene from Bangladesh (2009–2013)
Authors
Abu Naser Mohon
Mohammad Shafiul Alam
Abebe Genetu Bayih
Asongna Folefoc
Dea Shahinas
Rashidul Haque
Dylan R Pillai
Publication date
01-12-2014
Publisher
BioMed Central
Published in
Malaria Journal / Issue 1/2014
Electronic ISSN: 1475-2875
DOI
https://doi.org/10.1186/1475-2875-13-431

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