Volume 75, Issue 2
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


Antigenic variation in erythrocyte membrane protein 1, caused by a switch in transcription of the encoding gene, is an important feature of malaria. In this study, we quantified the relative abundance of gene transcripts present in parasite clones using real-time reverse transcription-polymerase chain reaction (RT-PCR) and conventional RT-PCR combined with cloning and sequencing, with the aim of directly comparing the results obtained. When there was sufficient abundance of RNA for the real-time RT-PCR assay to be operating within the region of good reproducibility, RT-PCR and real-time RT-PCR tended to identify the same dominant transcript, although some transcript-specific issues were identified. When there were differences in the estimated relative amounts of minor transcripts, the RT-PCR assay tended to produce higher estimates than real-time RT-PCR. These results provide valuable information comparing RT-PCR and real-time RT-PCR analysis of samples with small quantities of RNA as might be expected in the analysis of field or clinical samples.


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  • Received : 08 Jan 2006
  • Accepted : 01 Apr 2006

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