title: Genetic diversity of Plasmodium falciparum isolates from Pahang, Malaysia based on MSP-1 and MSP-2 genes.
abstract: BACKGROUND
  Malaria is still a public health problem in Malaysia especially in the interior parts of Peninsular Malaysia and the states of Sabah and Sarawak (East Malaysia). This is the first study on the genetic diversity and genotype multiplicity of Plasmodium falciparum in Malaysia.
  
  
  METHODS
  Seventy-five P. falciparum isolates were genotyped by using nested-PCR of MSP-1 (block 2) and MSP-2 (block 3).
  
  
  RESULTS
  MSP-1 and MSP-2 allelic families were identified in 65 blood samples. RO33 was the predominant MSP-1 allelic family identified in 80.0% (52/65) of the samples while K1 family had the least frequency. Of the MSP-2 allelic families, 3D7 showed higher frequency (76.0%) compared to FC27 (20.0%). The multiplicity of P. falciparum infection (MOI) was 1.37 and 1.20 for MSP-1 and MSP-2, respectively. A total of seven alleles were detected; of which three MSP-1 allelic families (RO33, MAD20 and K1) were monomorphic in terms of size while MSP-2 alleles were polymorphic (two 3D7 and two FC27). Heterozygosity (HE) was 0.57 and 0.55 for MSP-1 and MSP-2, respectively.
  
  
  CONCLUSIONS
  The study showed that the MOI of P. falciparum is low, reflected the low intensity of malaria transmission in Pahang, Malaysia; RO33 and 3D7 were the most predominant circulating allelic families. The findings showed that P. falciparum has low allelic diversity with a high frequency of alleles. As a result, antimalarial drug efficacy trials based on MSP genotyping should be carefully interpreted.
authors.affiliation: Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia. wahib_atrosh@yahoo.com
authors.forename: Wahib M
authors.initials: WM
authors.lastname: Atroosh
authors.forename: Hesham M
authors.initials: HM
authors.lastname: Al-Mekhlafi
authors.forename: Mohammed Ak
authors.initials: MA
authors.lastname: Mahdy
authors.forename: Riyadh
authors.initials: R
authors.lastname: Saif-Ali
authors.forename: Abdulsalam M
authors.initials: AM
authors.lastname: Al-Mekhlafi
authors.forename: Johari
authors.initials: J
authors.lastname: Surin
mesh_terms: D000328:Adult; D000483:Alleles; D000818:Animals; D000953:Antigens, Protozoan / Q000235:genetics*; D016054:DNA, Protozoan / Q000235:genetics; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D016778:Malaria, Falciparum / Q000469:parasitology*; D008296:Malaysia; D008297:Male; D020066:Merozoite Surface Protein 1 / Q000235:genetics*; D010963:Plasmodium falciparum / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D015800:Protozoan Proteins / Q000235:genetics*
chemical_list: D000953:Antigens, Protozoan; D016054:DNA, Protozoan; D020066:Merozoite Surface Protein 1; D015800:Protozoan Proteins; C065974:merozoite surface protein 2, Plasmodium