Novel pfk13 polymorphisms in Plasmodium falciparum population in Ghana

Abstract

The molecular determinants of Plasmodium falciparum artemisinin resistance are the single nucleotide polymorphisms in the parasite’s kelch propeller domain, pfk13. Validated and candidate markers are under surveillance in malaria endemic countries using artemisinin-based combination therapy. However, pfk13 mutations which may confer parasite artemisinin resistance in Africa remains elusive. It has therefore become imperative to report all observed pfk13 gene polymorphisms in malaria therapeutic efficacy studies for functional characterization. We herein report all novel pfk13 mutations observed only in the Ghanaian parasite population. In all, 977 archived samples from children aged 12 years and below with uncomplicated malaria from 2007 to 2017 were used. PCR/Sanger sequencing analysis revealed 78% (763/977) of the samples analyzed were wild type (WT) for pfk13 gene. Of the 214 (22%) mutants, 78 were novel mutations observed only in Ghana. The novel SNPs include R404G, P413H, N458D/H/I, C473W/S, R529I, M579T/Y, C580R/V, D584L, N585H/I, Q661G/L. Some of the mutations were sites and ecological zones specific. There was low nucleotide diversity and purifying selection at the pfk13 locus in Ghanaian parasite population. With increasing drug pressure and its consequent parasite resistance, documenting these mutations as baseline data is crucial for future molecular surveillance of P. falciparum resistance to artemisinin in Ghana.

Putative molecular markers of Plasmodium falciparum resistance to antimalarial drugs in malaria parasites from Ghana

“…Typically, areas with high transmission intensity show increased exchange of genetic material amongst the parasite population which subsequently leads to the development of spontaneous mutations that can confer resistance to antimalarial drugs ( 5 , 61 ). In addition, the observation of both zone-specific and shared mutations across the zones may indicate gene flow amongst individuals in the population through intra-country migration ( 5 , 6 , 62 ).…”

“…Molecular analysis of the P. falciparum genome revealed mutations in the kelch propeller gene (pfk13) to be associated with the development of parasite tolerance to ART and are being monitored in parasite populations as markers of drug resistance (2,4). ART resistance pfk13 candidate mutations and novel ones have been reported in Ghanaian isolates (5)(6)(7). A study conducted in Cambodia has also shown parasites with increased ring stage survival but lacking the pfk13 mutations which implies that there could be other genes involved and/or different resistance mechanisms (8).…”

In vitro susceptibility profile of Plasmodium falciparum clinical isolates from Ghana to antimalarial drugs and polymorphisms in resistance markers

“…This study did not detect pfk13 propeller domain mutations in the 29 parasite isolates. Since most pfk13 mutations detected earlier in Ghana appeared as low-frequency mutations (Matrevi et al, 2019;Matrevi et al, 2022), molecular surveillance of pfk13 mutations may require more extensive sampling efforts.…”

Anti-malarial resistance in Mozambique: Absence of Plasmodium falciparum Kelch 13 (K13) propeller domain polymorphisms associated with resistance to artemisinins

“…Some of the mutations are validated single nucleotide polymorphisms (SNPs), used as molecular markers for the surveillance of artemisinin-resistant malaria parasites (F446L, N458Y, M476I, Y493H, R539T, I543T, P553L, R561H, P574L, C580Y) (WHO, 2019). Recently, P. falciparum parasites carrying the validated SNPs F446I, M476I, P553L, R561H, P574L, C580Y and A675V have emerged and expanded or been identified in Africa [22], in Angola, Ghana [23], Mali, Rwanda [24][25][26][27]. In Mozambique, available studies on the prevalence of pfK13 SNPs, refer to parasite samples collected prior to 2018 [28][29][30][31].…”