Prevalence of the K76T mutation in the pfcrt gene of Plasmodium falciparum among chloroquine responders in India

Acta Trop. 2003 Jul;87(2):287-93. doi: 10.1016/s0001-706x(03)00021-4.

Abstract

Chloroquine-resistant Plasmodium falciparum needs to be monitored in the field for effective malaria control strategies. A point mutation K76T in the P. falciparum chloroquine resistance transporter (Pfcrt) protein has recently been proposed as a molecular marker for the faster detection of chloroquine-resistant falciparum malaria in field. We describe here the evaluation of this marker in Indian P. falciparum isolates. A total of 274 Indian P. falciparum isolates were analyzed for the K76T mutation. This mutation was detected in all the clinical isolates obtained from the in vivo chloroquine non-responders. But majority of the clinical isolates from chloroquine responders (71 of 74 patients, i.e. 96%) also harbored this mutation. The K76T mutation was indeed highly prevalent (91%) among 213 clinical isolates. There was a significant association between K76T mutation and the in vitro chloroquine response (P<0.05) but six isolates showed discordant results. In conclusion, the K76T mutation fails to differentiate majority of the chloroquine responders from that of the non-responders and thus will be of limited use in the field in India.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Animals
  • Antimalarials / therapeutic use*
  • Child
  • Chloroquine / therapeutic use*
  • DNA, Bacterial / chemistry
  • DNA, Bacterial / genetics
  • Drug Resistance / genetics
  • Female
  • Humans
  • India
  • Malaria, Falciparum / blood
  • Malaria, Falciparum / drug therapy*
  • Malaria, Falciparum / parasitology*
  • Male
  • Membrane Transport Proteins / chemistry
  • Membrane Transport Proteins / genetics
  • Middle Aged
  • Parasitic Sensitivity Tests
  • Plasmodium falciparum / genetics*
  • Point Mutation*
  • Polymerase Chain Reaction

Substances

  • Antimalarials
  • DNA, Bacterial
  • Membrane Transport Proteins
  • Chloroquine