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. 2022 Apr 25;4(4):000350.
doi: 10.1099/acmi.0.000350. eCollection 2022.

Genetic polymorphism of Plasmodium falciparum msp-1, msp-2 and glurp vaccine candidate genes in pre-artemisinin era clinical isolates from Lakhimpur district in Assam, Northeast India

Affiliations

Genetic polymorphism of Plasmodium falciparum msp-1, msp-2 and glurp vaccine candidate genes in pre-artemisinin era clinical isolates from Lakhimpur district in Assam, Northeast India

Vinayagam Sathishkumar et al. Access Microbiol. .

Abstract

Background: Northeast India shares its international border with Southeast Asia and has a number of malaria endemic zones. Monitoring genetic diversity of malaria parasites is important in this area as drug resistance and increasing genetic diversity form a vicious cycle in which one favours the development of the other. This retrospective study was done to evaluate the genetic diversity patterns in Plasmodium falciparum strains circulating in North Lakhimpur area of Assam in the pre-artemisinin era and compare the findings with current diversity patterns.

Methods: Genomic DNA extraction was done from archived blood spot samples collected in 2006 from malaria-positive cases in Lakhimpur district of Assam, Northeast India. Three antigenic markers of genetic diversity were studied - msp-1 (block-2), msp-2 (block-3) and the glurp RII region of P. falciparum using nested PCR.

Results: Allelic diversity was examined in 71 isolates and high polymorphism was observed. In msp-1, eight genotypes were detected; K1 (single allele), MAD20 (six different alleles) and RO33 (single allele) allelic families were noted. Among msp-2 genotypes, 22 distinct alleles were observed out of which FC27 had six alleles and IC/3D7 had 16 alleles. In RII region of glurp, nine genotypes were obtained. Expected heterozygosity (H E) values of the three antigenic markers were 0.72, 0.81 and 0.88, respectively. Multiplicity of infection (MOI) values noted were 1.28, 1.84 and 1.04 for msp-1, msp-2 and glurp, respectively.

Conclusion: Results suggest a high level of genetic diversity in P. falciparum msp (block-2 of msp-1 and block-3 of msp-2) and the glurp RII region in Northeast India in the pre-artemisinin era when chloroqunine was the primary drug used for uncomplicated falciparum malaria. Comparison with current studies have revealed that the genetic diversity in these genes is still high in this region, complicating malaria vaccine research.

Keywords: India; Merozoite surface protein; Plasmodium falciparum; drug resistance; glutamate-rich protein; vaccines.

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Conflict of interest statement

The authors declare that there are no conflicts of interest.

Figures

Fig. 1.
Fig. 1.
Allele frequencies of P. falciparum msp-1 detected by nPCR from archived (2006) samples collected in Lakhimpur, Assam.
Fig. 2.
Fig. 2.
Allele frequencies of P. falciparum msp-2 detected by nPCR from archived (2006) samples collected in Lakhimpur, Assam: (a) frequency of FC27; (b) frequency of IC/3D7.
Fig. 3.
Fig. 3.
Allele frequencies of P. falciparum glurp detected by nPCR from archived (2006) samples collected in Lakhimpur, Assam.

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References

    1. WHO World Malaria Report 2021. Geneva: World Health Organization; 2021.
    1. Mohapatra PK, Prakash A, Taison K, Negmu K, Gohain AC, et al. Evaluation of chloroquine (CQ) and sulphadoxine/pyrimethamine (SP) therapy in uncomplicated falciparum malaria in Indo-Myanmar border areas. Trop Med Int Health. 2005;10:478–483. doi: 10.1111/j.1365-3156.2005.01401.x. - DOI - PubMed
    1. Berzins K. Merozoite antigens involved in invasion. Chem Immunol. 2002;80:125–143. doi: 10.1159/000058843. - DOI - PubMed
    1. Genton B, Reed ZH. Asexual blood-stage malaria vaccine development: facing the challenges. Curr Opin Infect Dis. 2007;20:467–475. doi: 10.1097/QCO.0b013e3282dd7a29. - DOI - PubMed
    1. Gaur D, Mayer DCG, Miller LH. Parasite ligand–host receptor interactions during invasion of erythrocytes by Plasmodium merozoites . Int J Parasitol. 2004;34:1413–1429. doi: 10.1016/j.ijpara.2004.10.010. - DOI - PubMed

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