Genetic markers associated with antimalarial drug resistance and haemoglobin genotypes among malaria patients in Kaduna State, Nigeria

Abstract

Background Malaria is a disease of public health concern in Nigeria and sub-Saharan Africa. The emergence of drug resistance, particularly among P. falciparum strains, has been a major contributor to the global burden of malaria. This research was aimed at detecting genetic markers (pfcrt, pfmdr1, pfdhfr, pfdhps, pfatpase6) associated with antimalarial drug resistance and assessing the distribution of haemoglobin genotypes among malaria patients in of Kaduna State, Nigeria. Methods Three hundred (300) blood samples were collected from consenting individuals attending selected hospitals, in the three senatorial districts of Kaduna State, Nigeria. A structured questionnaire was used to obtain relevant data from the study participants. The samples were screened for malaria parasites by microscopy and malaria rapid diagnostic test kit. Deoxyribonucleic acid was extracted from one third of the malaria positive samples, and Polymerase Chain Reaction (PCR) was used for detection of the drug resistance genes. Pfcrt, pfmdr1, pfdhfr, pfdhps and pfatpase6 genes were detected at expected amplicon sizes from the malaria positive samples. The pfatpase6 PCR amplicons were sequenced and a phylogenetic tree was created using MEGA X to determine their relatedness to published sequences. Results Pfcrt (80%) had the highest prevalence, followed by pfdhfr (60%), pfmdr1 (36%) and pfdhps (8%). Pfatpase6 was also detected in 73.3% of the samples. The phylogenetic tree showed that all the pfatpase6 gene sequences (both the ones from this study and those published in NCBI Genbank) had the same origin and were closely related. However, the sequences from NCBI Genbank were from one clade; arising from a common ancestor (monophyletic) thus they were more closely related to themselves, than to the pfatpase6 sequences obtained in this study. Of all the malaria positive participants, those with HbAA (73%) haemoglobin genotype had the highest percentage followed by HbAS (23%), HbAC (3%) and HbSS (1). Conclusion We detected Plasmodium falciparum genes associated with drug resistance to commonly used antimalarials in the study area. Expression of these genes could have serious consequences in the treatment of malaria. The percentage of Plasmodium falciparum malaria was higher among persons with HbAA than those with HbAS, HbAC and HbS.