Single-nucleotide Polymorphisms of Artemisinin Resistance-related pfubp1 and pfap2mu Genes in Imported Plasmodium Falciparum to Wuhan, China

Abstract Background Molecular markers for monitoring resistance could help improve malaria treatment policies. Delayed clearance of Plasmodium falciparum by Artemisinin-based Combination Therapies (ACTs) has been reported in several countries. In addition to the PfKelch13 (pfk13) , new drug resistance genes, the ubiquitin-specific protease 1 ( pfubp1 ) and the eadaptor protein complex 2 mu subunit ( pfap2mu ) have been identified as being linked to ACTs. This study investigated the prevalence of single-nucleotide polymorphisms (SNPs) in clinical P. falciparum isolates pfubp1 and pfap2mu imported from Africa and Southeast Asia (SEA) to Wuhan, China, to provide baseline data for antimalarial resistance monitoring in this region. Methods Peripheral Blood samples were collected in Wuhan, China, from August 2011 to December 2019. The SNPs of Pfubp1 and pfap2mu of P. falciparum were determined by nested PCR and Sanger sequencing. Results In total, 296 samples were collected. Subsequently, 92.23% (273/296) were successfully amplified and sequenced for the Pfubp1 . There were 60.07% (164/273) wild strains and 39.93% (109/273) mutant strains. For the pfap2mu gene, it was divided into three fragments for amplification, 82.77% (245/296), 90.20% (267/296) and 94.59% (280/296) were sequenced successfully respectively. Genotypes reportedly associated with ACTs resistance detected in this study included pfubp1 D1525 E as well as E1528 D and pfap2mu S160 N . The mutation prevalence rates were 10.99% (30/273), 13.19% (36/273) and 11.24% (30/267), respectively. These are all focused on Congo, Nigeria and Angola. And known delayed-clearance parasite mutation has also been found in SEA. Conclusions The existence of mutation sites of known clearance genes detected in the isolates in this study, including D1525 E and E1528 D in the pfubp1 gene, and S160 N in the pfap2mu gene, further proved the risk of ACTs resistance. Constant vigilance is therefore needed to protect the effectiveness of ACTs, and to prevent the spread of drug-resistant P. falciparum . Further studies in malaria-endemic countries are needed to further validate potential genetic markers for monitoring parasite populations in Africa and SEA.