title: Limited artemisinin resistance-associated polymorphisms in Plasmodium falciparum K13-propeller and PfATPase6 gene isolated from Bioko Island, Equatorial Guinea.
abstract: OBJECTIVE
  With emergence and geographically expanding of antimalarial resistance worldwide, molecular markers are essential tool for surveillance of resistant Plasmodium parasites. Recently, single-nucleotide polymorphisms (SNPs) in the PF3D7_1343700 kelch propeller (K13-propeller) domain are shown to be associated with artemisinin (ART) resistance in vivo and in vitro. This study aims to investigate the ART resistance-associated polymorphisms of K13-propeller and PfATPase6 genes in Plasmodium falciparum isolates from Bioko Island, Equatorial Guinea (EG).
  
  
  METHODS
  A total of 172 samples were collected from falciparum malaria patients on Bioko Island between 2013 and 2014. The polymorphisms of K13-propeller and PfATPase6 genes were analyzed by Nest-PCR and sequencing.
  
  
  RESULTS
  Sequences of K13-propeller and PfATPase6 were obtained from 90.74% (98/108) and 91.45% (139/152) samples, respectively. The 2.04% (2/98) cases had non-synonymous K13-propeller A578S mutation but no found the mutations associated with ART resistance in Southeast Asia. For PfATPase6, the mutations were found at positions N569K and A630S with the mutation prevalence of 7.91% (11/139) and 1.44% (2/139), respectively. In addition, a sample with the mixed type at position I723V was discovered (0.72%, 1/139).
  
  
  CONCLUSIONS
  This study initially offers an insight of K13-propeller and PfATPase6 polymorphisms on Bioko Island, EG. It suggests no widespread ART resistance or tolerance in the region, and might be helpful for developing and updating guidance for the use of ART-based combination therapies (ACTs).
authors.affiliation: Institute of Basic Medical Sciences, College of Basic Medicine, Department of Infectious Diseases, Renmin Hospital, Hubei University of Medicine, Shiyan 442000, People's Republic of China.
authors.forename: Jian
authors.initials: J
authors.lastname: Li
authors.affiliation: Laboratory Medical Center, Huizhou Municipal Central Hospital, Huizhou 516001, People's Republic of China; The Chinese Medical Aid Team to the Republic of Equatorial Guinea, Guangzhou 510000, People's Republic of China.
authors.forename: Jiangtao
authors.initials: J
authors.lastname: Chen
authors.affiliation: The Chinese Medical Aid Team to the Republic of Equatorial Guinea, Guangzhou 510000, People's Republic of China.
authors.forename: Dongde
authors.initials: D
authors.lastname: Xie
authors.affiliation: Central Blood Transfusion Service, Department of Medical Laboratory Science, Malabo Regional Hospital, Malabo 999115, Equatorial Guinea.
authors.forename: Urbano Monsuy
authors.initials: UM
authors.lastname: Eyi
authors.affiliation: Central Blood Transfusion Service, Department of Medical Laboratory Science, Malabo Regional Hospital, Malabo 999115, Equatorial Guinea.
authors.forename: Rocio Apicante
authors.initials: RA
authors.lastname: Matesa
authors.affiliation: Central Blood Transfusion Service, Department of Medical Laboratory Science, Malabo Regional Hospital, Malabo 999115, Equatorial Guinea.
authors.forename: Maximo Miko
authors.initials: MM
authors.lastname: Ondo Obono
authors.affiliation: Central Blood Transfusion Service, Department of Medical Laboratory Science, Malabo Regional Hospital, Malabo 999115, Equatorial Guinea.
authors.forename: Carlos Sala
authors.initials: CS
authors.lastname: Ehapo
authors.affiliation: Laboratory Medical Center, Chaozhou Central Hospital, Southern Medical University, Chaozhou 521021, People's Republic of China.
authors.forename: Liye
authors.initials: L
authors.lastname: Yang
authors.affiliation: Laboratory Medical Center, Chaozhou Central Hospital, Southern Medical University, Chaozhou 521021, People's Republic of China.
authors.forename: Huitian
authors.initials: H
authors.lastname: Yang
authors.affiliation: Laboratory Medical Center, Chaozhou Central Hospital, Southern Medical University, Chaozhou 521021, People's Republic of China; Department of Histology and Embryology, Shantou University Medical College, Shantou 515000, Guangdong, People's Republic of China. Electronic address: Konfutea@hotmail.com.
authors.forename: Min
authors.initials: M
authors.lastname: Lin
mesh_terms: D037621:Artemisinins / Q000494:pharmacology*; D000252:Calcium-Transporting ATPases / Q000235:genetics*; D016054:DNA, Protozoan / Q000235:genetics*; D004351:Drug Resistance / Q000235:genetics*; D016703:Equatorial Guinea / Q000453:epidemiology; D005838:Genotype; D006801:Humans; D016778:Malaria, Falciparum / Q000453:epidemiology / Q000469:parasitology*; D009154:Mutation; D020125:Mutation, Missense; D010963:Plasmodium falciparum / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide; D015800:Protozoan Proteins / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D037621:Artemisinins; D016054:DNA, Protozoan; D015800:Protozoan Proteins; D000252:Calcium-Transporting ATPases
keywords: Artemisinin resistance; K13-propeller; Plasmodium falciparum; Polymorphism