Novel quadruple mutations in dihydropteroate synthase genes of Plasmodium falciparum in West Bengal, India.
OBJECTIVE
To evaluate the anti-folate (sulphadoxine)-resistant pattern in Kolkata, one of the malaria endemic zones of Eastern India.


METHODS
At first, 107 P. falciparum suspected cases were enrolled in this study. Ninety isolates (84.11%) of 107 suspected cases were analysed, as they had mono-infection with P. falciparum. In vitro susceptibility assays were performed in all 90 isolates. Parasitic DNA was isolated by phenol-chloroform extraction method and polymerase chain reaction was followed by restriction fragment length polymorphism analysis of different codons of the pfdhps gene (436, 437, 540, 581 and 613).


RESULTS
Among 90 isolates from Kolkata, dhps mutant isolates at codons 436, 437, 540, 581 and 613 were found in 53.33%, 67.78%, 46.66%, 15.56% and 45.55%, respectively. In vitro sulphadoxine resistance was found in 49 isolates (54.44%). Interestingly we found 33 isolates (36.67%) with quadruple AGEAT mutant allele, of which 32 isolates (96.97%) were highly sulphadoxine resistant (P < 0.01) in vitro.


CONCLUSIONS
Our present findings implicate that because of enormous drug (sulphfadoxine) pressure, novel AGEAT mutation was highly correlated (P < 0.01) with sulphadoxine resistance.
Immunology and Microbiology Laboratory, Vidyasagar University, Midnapore, India  Division of Parasitology, Calcutta School of Tropical Medicine, Kolkata, India.
Sabyasachi
S
Das
Subhankari P
SP
Chakraborty
Satyajit
S
Tripathy
Amiyakumar
A
Hati
Somenath
S
Roy
D000962:Antimalarials / Q000627:therapeutic use; D016054:DNA, Protozoan / Q000235:genetics; D004094:Dihydropteroate Synthase / Q000235:genetics*; D004351:Drug Resistance; D005838:Genotype; D006801:Humans; D007194:India; D016778:Malaria, Falciparum / Q000188:drug therapy / Q000235:genetics*; D008969:Molecular Sequence Data; D009154:Mutation; D010963:Plasmodium falciparum / Q000235:genetics*; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D015800:Protozoan Proteins / Q000235:genetics*; D013413:Sulfadoxine / Q000627:therapeutic use
D000962:Antimalarials; D016054:DNA, Protozoan; D015800:Protozoan Proteins; D013413:Sulfadoxine; D004094:Dihydropteroate Synthase