title: Vivax malaria in Mauritania includes infection of a Duffy-negative individual.
abstract: BACKGROUND
  Duffy blood group polymorphisms are important in areas where Plasmodium vivax is present because this surface antigen is thought to act as a key receptor for this parasite. In the present study, Duffy blood group genotyping was performed in febrile uninfected and P. vivax-infected patients living in the city of Nouakchott, Mauritania.
  
  
  METHODS
  Plasmodium vivax was identified by real-time PCR. The Duffy blood group genotypes were determined by standard PCR followed by sequencing of the promoter region and exon 2 of the Duffy gene in 277 febrile individuals. Fisher's exact test was performed in order to assess the significance of variables.
  
  
  RESULTS
  In the Moorish population, a high frequency of the FYBES/FYBES genotype was observed in uninfected individuals (27.8%), whereas no P. vivax-infected patient had this genotype. This was followed by a high level of FYA/FYB, FYB/FYB, FYB/FYBES and FYA/FYBES genotype frequencies, both in the P. vivax-infected and uninfected patients. In other ethnic groups (Poular, Soninke, Wolof), only the FYBES/FYBES genotype was found in uninfected patients, whereas the FYA/FYBES genotype was observed in two P. vivax-infected patients. In addition, one patient belonging to the Wolof ethnic group presented the FYBES/FYBES genotype and was infected by P. vivax.
  
  
  CONCLUSIONS
  This study presents the Duffy blood group polymorphisms in Nouakchott City and demonstrates that in Mauritania, P. vivax is able to infect Duffy-negative patients. Further studies are necessary to identify the process that enables this Duffy-independent P. vivax invasion of human red blood cells.
authors: Unité de Recherche en Biologie et Epidémiologie Parasitaires, Institut de Recherche Biomédicale des Armées, Parc du Pharo, Marseille Cedex, France. nathalie_wurtz@yahoo.fr
authors: Nathalie
authors: N
authors: Wurtz
authors: Khadijetou
authors: K
authors: Mint Lekweiry
authors: Hervé
authors: H
authors: Bogreau
authors: Bruno
authors: B
authors: Pradines
authors: Christophe
authors: C
authors: Rogier
authors: Ali
authors: A
authors: Ould Mohamed Salem Boukhary
authors: Jamal Eddine
authors: JE
authors: Hafid
authors: Mohamed Salem
authors: MS
authors: Ould Ahmedou Salem
authors: Jean-François
authors: JF
authors: Trape
authors: Leonardo K
authors: LK
authors: Basco
authors: Sébastien
authors: S
authors: Briolant
mesh_terms: D004375:Duffy Blood-Group System / Q000235:genetics*; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D016780:Malaria, Vivax / Q000453:epidemiology*; D008435:Mauritania / Q000453:epidemiology; D010966:Plasmodium vivax / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D011956:Receptors, Cell Surface / Q000235:genetics*; D017422:Sequence Analysis, DNA
chemical_list: C473745:ACKR1 protein, human; D004375:Duffy Blood-Group System; D011956:Receptors, Cell Surface