Genetic variation in histidine rich proteins among Indian Plasmodium falciparum population: possible cause of variable sensitivity of malaria rapid diagnostic tests

• Published in: Malaria Journal
• Main Authors: Kumar Navin, Singh Jai PN, Pande Veena, Mishra Neelima, Srivastava Bina, Kapoor Ridhima, Valecha Neena, Anvikar Anupkumar R
• Format: Article in Journal/Newspaper
• Language: English
• Published: BMC 2012
• Subjects: Plasmodium falciparum Histidine rich protein 2; Plasmodium falciparum Histidine rich protein 3; Rapid Diagnostic Tests; Genetic polymorphism; India; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic; Indian
• Online Access: https://doi.org/10.1186/1475-2875-11-298; https://doaj.org/article/6d6479fd5f9648a49c95e2b8cca09ecc

Abstract Background Rapid diagnostic tests (RDTs) have revolutionized the diagnosis of malaria. Among the various factors affecting RDTs sensitivity is genetic variation of the antigen used. The genetic variation in PfHRP2 and PfHRP3 proteins was studied among the Indian Plasmodium falciparum isolates. Methods One hundred and forty isolates of P. falciparum were collected from six geographical regions of India. Target genes encoding PfHRP2 and PfHRP3 antigens were sequenced to study genetic polymorphism. Minimum detection limit giving a positive rapid diagnostic test was also determined. Results Extensive variations were observed in amino acid repeat types of PfHRP2 and PfHRP3. PfHRP2 exhibited more polymorphism than PfHRP3. Significant relation was observed between type 2 and type 7 repeats and RDT detection rate as higher number of these repeats showed better sensitivity with RDTs. Conclusion The results provide insights into the genetic diversity of Pfhrp2 and Pfhrp3 genes among Indian P. falciparum population and its relation to RDT sensitivity.