Plasmodium falciparum genetic diversity in malaria endemic areas of Pakistan using merozoite surface protein 2 (msp-2)

Abstract

The detailed description of parasites living in the areas of malaria endemic is essential to assess the achievement of current strategies of controlling malarial disease. The purpose of this study is to inspect the inherited multiplicity of the Plasmodium falciparum, obtained from malaria endemic areas of Pakistan, using the merozoite surface protein-2 (msp-2), a highly polymorphic gene as a genetic marker. Blood samples of Plasmodium falciparum positive patients were collected from different Basic Health Units in different provinces of Pakistan during period from January 2018 to January 2019. DNA from Plasmodium falciparum positive samples was isolated and genotyped for msp-2 using allele-specific nested polymerase chain reaction (PCR). Total 209 isolates were collected in which 179 show positive result through PCR and msp-2 recognized in 85 (47.4%) isolates. Allele of the msp-2 gene perceived the 3D7/IC allelic family in 42.3% and FC27 allelic family typing in 57.6%. A total of 25 different msp-2 genotypes were detected in which 13 were from FC27 family and 12 were from 3D7/IC family. Overall mean multiplicity of infections (MOI) was 1.20 (95 percent CI 1.00-1.50). The msp-2 locus had a heterozygosity index of 0.5. There were no differences in MOI between age groups of study. The parasite multiplicity density of infection has negative correlation found and also significant (P-value = 0.02). Plasmodium falciparum isolates from Pakistan's endemic areas are mostly monoclonal, with a low degree of MOI and moderate genetic diversity in the research population.