Development of a Dlc Gene Based Assay for Detection of Selected Plasmodium Species.

Abstract

Malaria is a disease caused by Plasmodiuma protozoa parasite in the phylum Apicomplexa. The disease has a profound impact on public health, economyand social structures of many developing countries. To ensure patients receive appropriate treatment of malaria, accurate differentiation of the Plasmodium species is key. There are various techniques applied for the diagnosis of the disease among them polymerase chain reaction method. This technique has proved to be the most sensitive and specific compared to microscopy. PCR can detect low parasitaemia at levels undetectable by microscopy, it can also differentiate among Plasmodium species and it is a valuable tool for epidemiological diagnosis. Many laboratories are currently developing more specific PCR using alternative target genes to improve on species identification. Based on an In silico study, the gene sequence of TcTex 1 gene was found to be conserved within the Plasmodium species. In this study, PCR primers were applied with the aim ofdetecting P. falciparum, the most common malaria causing parasite in Kenya and P. knowlesi, P. cynomolgispecies responsible for the emerging zoonotic transmissions in humans. The study entailed the designing of diagnostic genus and species-specific primer sets within the TcTex1 dlc gene. The diagnostic primers weretested for specificity on the differentPlasmodiumspecies and population samples usingstandardPCR.The findings demonstrate that PCR targeting Plasmodium dlcTctex1 sub-unit gene can be used for P. falciparum species identification. The results also indicate that there could be probable P. knowlesi infections in the coastal region of Kenya, a malaria endemic area. A bioinformatics approach that entailed Artemis software analysis was used to xv determine the targetgene chromosomal location, organization and copy number. The data generated showed that the gene has acoding region and occurs as a single copy in P. knowlesi chromosome 9 and P. falciparum chromosome 11. The data presented in this study shows that TcTex 1 dlc gene can be used as an alternative malaria diagnostic target.