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. 2006 Apr;50(4):1546-9.
doi: 10.1128/AAC.50.4.1546-1549.2006.

Quadruple mutations in dihydrofolate reductase of Plasmodium falciparum isolates from Car Nicobar Island, India

Anwar Ahmed  1 , Manoj K Das, Vas Dev, Muheet A Saifi, Wajihullah, Yagya D Sharma
Affiliations

Quadruple mutations in dihydrofolate reductase of Plasmodium falciparum isolates from Car Nicobar Island, India

Anwar Ahmed et al. Antimicrob Agents Chemother. 2006 Apr.

Abstract

Quadruple mutations in the Plasmodium falciparum dihydrofolate reductase (PFDHFR) enzyme give rise to the highest level of pyrimethamine resistance leading to treatment failures. We describe here the presence of these quadruple mutations in a majority of P. falciparum isolates from Car Nicobar (Andaman and Nicobar) Island, India. Isolates from the mainland, however, continue to show a prevalence of double PFDHFR mutations and some with triple but none with quadruple mutations. In conclusion, the antifolate drug pressure is very high in the island, which should be a cause of concern for the malaria control program in the country.

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Figures

FIG. 1.
FIG. 1.
Mutation rates in the P. falciparum DHFR enzyme sequence. (A) Mutation rate in individual pfdhfr codons. (B) Percent prevalence of (total number of) PFDHFR mutations. n, number of P. falciparum isolates.
FIG. 2.
FIG. 2.
Regional distribution of P. falciparum dhfr mutations (A) and its genotypes (B) among Indian isolates. Mutated amino acids are underlined. n, number of P. falciparum isolates; A&N, Andaman and Nicobar.
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