Allelic frequency of 2 and genes in isolates from Awka, Anambra, Nigeria.

INTRODUCTION

The genetic diversity of correlates with its pathogenicity, therefore design of evidence-based intervention strategies to eradicate malaria requires genetic diversity surveillance. This study characterised the allelic frequencies and genetic diversity of parasites isolated from Awka, Nigeria.

MATERIALS AND METHODS

Genomic DNA was extracted from 177 isolates and the polymorphic regions of the and genes were genotyped by nested polymerase chain reaction (PCR).

RESULTS

Two alleles (3D7 and FC27) were analysed. The 3D7 (93.55%) allelic family was predominant in positivie isolates. Polyclonal infection was observed in 24 (38.71%) isolates. Twenty-one distinct alleles were detected, with fragment sizes ranging from 200 bp to 1200 bp. The 300 bp allelic fragment (26.83%) was predominant for the 3D7 allele, while the 400 bp allelic fragment (29.54%) was predominant for the FC27 allele. The multiplicity of infection (MoI) in was 2.03, and the expected Heterozygosity (He) was 0.34. Sixty-nine isolates (38.98%) were positive for the RII repeat region of the gene. For the gene, nine alleles were detected for fragment sizes ranging from 200 bp to 1150 bp, and the most prevalent allelic fragment was 200 bp (19%). The MoI and He for the gene were 0.45 and 0.98, respectively.

CONCLUSIONS

The high level of polyclonal infections with parasites observed in this study indicates extensive genetic diversity in the study area. The data provide important baseline information that can be implemented in developing malaria control strategies and elimination in the study area and Nigeria.