Skip to main content
  • Poster presentation
  • Open access
  • Published:

Large differences in variability for genes associated with antimalarial drug resistance between samples from Tanzania and Ethiopia


Changes in antimalarial drug policy lead to selection of the most successful parasite clones. In spite of a change to Artemisinin Combination Therapy (ACT), we have earlier shown a low degree of variability for the chloroquine resistance marker pfcrt in samples of Plasmodium falciparum from Ethiopia with 100% carrying the crucial K76T variant [1].

Materials and methods

The study material was collected in the Shalla district, Oromia, Ethiopia, and in different parts of Tanzania. Genetic polymorphisms in the genes pfmdr1 and pfubp1 were analysed by PCR and nucleotide sequence determinations.


A surprising finding was that a majority of Ethiopian isolates carried the wild type variant of pfmdr1. The majority of samples from different regions of Tanzania were wild type for both pfcrt and pfmdr1. Analysis of a variable linker region in pfmdr1 showed substantial variation in samples from Tanzania, but minimal variation in samples from Ethiopia. The variable part consists of consecutive NDN residues. The dominating variant in Ethiopians was 7/2/9 and 7/2/10 in Tanzania. The same pattern was seen for a variable part of the pfubp1 gene, where all Ethiopian samples were identical to 3D7. In 19 Tanzanian samples only 8 were identical to 3D7 with 5 other variants. A polymorphism at codon 1528, detected previously in Kenyan samples [2] was found in 2 Tanzanian samples.


While the presence of the mutant variant of pfcrt in the Ethiopian samples can be explained by continued use of chloroquine in Ethiopia for treatment of P. vivax, the selection of wild type pfmdr1 could be a consequence of using ACT for treatment of P. falciparum. In general, the variability in both studied genes was greater in Tanzania than in Ethiopia. There are no data yet to link the variability in pfubp1 to efficacy of ACT.


  1. Golassa L, Enweji N, Erko B, Aseffa A, Swedberg G: High prevalence of pfcrt-CVIET haplotype in isolates from asymptomatic and symptomatic patients in south-central Oromia, Ethiopia. Malaria J. 2014, 13: 120-10.1186/1475-2875-13-120.

    Article  Google Scholar 

  2. Borrmann S: Genome-wide screen identifies new candidate genes associated with artemisinin susceptibility in Plasmodium falciparum in Kenya. Sci Rep. 2013, 3: 3318-

    Article  PubMed Central  PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations


Rights and permissions

Open Access  This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.

The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.

To view a copy of this licence, visit

The Creative Commons Public Domain Dedication waiver ( applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Golassa, L., Enweji, N., Swedberg, G. et al. Large differences in variability for genes associated with antimalarial drug resistance between samples from Tanzania and Ethiopia. Malar J 13 (Suppl 1), P87 (2014).

Download citation

  • Published:

  • DOI: