title: Genetic Diversity of Plasmodium falciparum Populations in Malaria Declining Areas of Sabah, East Malaysia.
abstract: Malaysia has a national goal to eliminate malaria by 2020. Understanding the genetic diversity of malaria parasites in residual transmission foci can provide invaluable information which may inform the intervention strategies used to reach elimination targets. This study was conducted to determine the genetic diversity level of P. falciparum isolates in malaria residual foci areas of Sabah. Malaria active case detection was conducted in Kalabakan and Kota Marudu. All individuals in the study sites were screened for malaria infection by rapid diagnostic test. Blood from P. falciparum-infected individuals were collected on filter paper prior to DNA extraction. Genotyping was performed using merozoite surface protein-1 (MSP-1), merozoite surface protein-2 (MSP-2), glutamate rich protein (GLURP) and 10 neutral microsatellite loci markers. The size of alleles, multiplicity of infection (MOI), mean number of alleles (Na), expected heterozygosity (He), linkage disequilibrium (LD) and genetic differentiation (FST) were determined. In Kalabakan, the MSP-1 and MSP-2 alleles were predominantly K1 and FC27 family types, respectively. The GLURP genotype VI (751-800 bp) was predominant. The MOI for MSP-1 and MSP-2 were 1.65 and 1.20, respectively. The Na per microsatellite locus was 1.70. The He values for MSP-1, MSP-2, GLURP and neutral microsatellites were 0.17, 0.37, 0.70 and 0.33, respectively. In Kota Marudu, the MSP-1 and MSP-2 alleles were predominantly MAD20 and 3D7 family types, respectively. The GLURP genotype IV (651-700 bp) was predominant. The MOI for both MSP-1 and MSP-2 was 1.05. The Na per microsatellite locus was 3.60. The He values for MSP-1, MSP-2, GLURP and neutral microsatellites were 0.24, 0.25, 0.69 and 0.30, respectively. A significant LD was observed in Kalabakan (0.495, p<0.01) and Kota Marudu P. falciparum populations (0.601, p<0.01). High genetic differentiation between Kalabakan and Kota Marudu P. falciparum populations was observed (FST = 0.532). The genetic data from the present study highlighted the limited diversity and contrasting genetic pattern of P. falciparum populations in the malaria declining areas of Sabah.
authors.affiliation: Herbal Medicine Research Center, Institute for Medical Research, Kuala Lumpur, Malaysia.
authors.forename: Mohd Ridzuan
authors.initials: MR
authors.lastname: Mohd Abd Razak
authors.affiliation: Herbal Medicine Research Center, Institute for Medical Research, Kuala Lumpur, Malaysia.
authors.forename: Umi Rubiah
authors.initials: UR
authors.lastname: Sastu
authors.affiliation: Herbal Medicine Research Center, Institute for Medical Research, Kuala Lumpur, Malaysia.
authors.forename: Nor Azrina
authors.initials: NA
authors.lastname: Norahmad
authors.affiliation: Zonal Public Health Laboratory, Tamale Teaching Hospital, Tamale, Northern Region, Ghana, West Africa.
authors.forename: Abass
authors.initials: A
authors.lastname: Abdul-Karim
authors.affiliation: Herbal Medicine Research Center, Institute for Medical Research, Kuala Lumpur, Malaysia.
authors.forename: Amirrudin
authors.initials: A
authors.lastname: Muhammad
authors.affiliation: Herbal Medicine Research Center, Institute for Medical Research, Kuala Lumpur, Malaysia.
authors.forename: Prem Kumar
authors.initials: PK
authors.lastname: Muniandy
authors.affiliation: Sabah State Health Department, Rumah Persekutuan, Kota Kinabalu, Sabah, Malaysia.
authors.forename: Jenarun
authors.initials: J
authors.lastname: Jelip
authors.affiliation: Sabah State Health Department, Rumah Persekutuan, Kota Kinabalu, Sabah, Malaysia.
authors.forename: Christina
authors.initials: C
authors.lastname: Rundi
authors.affiliation: Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
authors.forename: Mallika
authors.initials: M
authors.lastname: Imwong
authors.affiliation: Vector Borne Disease Sector, Disease Control Division, Ministry of Health, Federal Government Administrative Centre, Putrajaya, Malaysia.
authors.forename: Rose Nani
authors.initials: RN
authors.lastname: Mudin
authors.affiliation: Herbal Medicine Research Center, Institute for Medical Research, Kuala Lumpur, Malaysia.
authors.forename: Noor Rain
authors.initials: NR
authors.lastname: Abdullah
mesh_terms: D000483:Alleles; D000953:Antigens, Protozoan / Q000235:genetics; D005787:Gene Frequency / Q000235:genetics; D056426:Genetic Loci; D014644:Genetic Variation; D005838:Genotype; D005843:Geography; D015810:Linkage Disequilibrium / Q000235:genetics; D016778:Malaria, Falciparum / Q000469:parasitology*; D008296:Malaysia; D020066:Merozoite Surface Protein 1 / Q000235:genetics; D018895:Microsatellite Repeats / Q000235:genetics; D010802:Phylogeny; D010963:Plasmodium falciparum / Q000235:genetics* / Q000302:isolation & purification; D011110:Polymorphism, Genetic; D015800:Protozoan Proteins / Q000235:genetics
chemical_list: D000953:Antigens, Protozoan; D020066:Merozoite Surface Protein 1; D015800:Protozoan Proteins; C065974:merozoite surface protein 2, Plasmodium