Volume 17, Number 3—March 2011
Dispatch
Multidrug-Resistant Genotypes of Plasmodium falciparum, Myanmar
Table 1
Prevalence of point mutation haplotypes in pfdhfr and pfdhps in clinical samples from Kachin State, northeast Myanmar, 2007–2009*
Gene | Haplotype | Codon† | Haplotype prevalence,‡ % |
||
---|---|---|---|---|---|
2007, n = 41 | 2008, n = 40 | 2009, n = 36 | |||
Pfdhfr (51, 59, 108, 164) |
Wild-type | NCSI | 2.4 | – | – |
Double mutations | NRNI | 9.8 | 5.0 | – | |
Triple mutations | NRNL | 31.7a | 25.0b | 36.1a | |
IRNI | 14.6a | 7.5b | 16.7a | ||
Quadruple mutations |
IRNL |
41.5a |
62.5b |
47.2a |
|
Pfdhps (436, 437, 540, 581) | Wild-type | SAKA | 2.4 | – | 2.8 |
Single mutation | SGKA | – | 2.5 | 2.8 | |
Double mutations | SGEA | 9.8 | 2.5 | – | |
SGNA | 2.4 | – | – | ||
Triple mutations | SGEG | 26.8a | 35.0b | 19.4c | |
SGNG | 2.4 | 2.5 | – | ||
AGEA | 48.8a | 45.0a | 52.8a | ||
AGNA | 7.3 | – | 8.3 | ||
Quadruple mutations | AGEG | – | 10.0 | 11.1 | |
AGNG | – | 2.5 | 2.8 |
*Pfdhfr, Plasmodium falciparum dihydrofolate reductase; Pfdhps, P. falciparum dihydropoteroate synthase; –, no such haplotype detected.
†Codons in boldface indicate mutated amino acids.
‡χ2 test was performed with all data points of the 2 genes, which showed that overall haplotype prevalence differed significantly between the years (χ2 test, p<0.0001, χ2 = 76.49, df = 28). Major dhfr and dhps haplotypes were individually compared. For each haplotype (in the same row), the labeling by different letters denotes significant difference between the years (χ2 test, p<0.05).
1These authors contributed equally to this article.