title: Characterization of G6PD genotypes and phenotypes on the northwestern Thailand-Myanmar border.
abstract: Mutations in the glucose-6-phosphate dehydrogenase (G6PD) gene result in red blood cells with increased susceptibility to oxidative damage. Significant haemolysis can be caused by primaquine and other 8-aminoquinoline antimalarials used for the radical treatment of Plasmodium vivax malaria. The distribution and phenotypes of mutations causing G6PD deficiency in the male population of migrants and refugees in a malaria endemic region on the Thailand-Myanmar border were characterized. Blood samples for G6PD fluorescent spot test (FST), G6PD genotyping, and malaria testing were taken from 504 unrelated males of Karen and Burman ethnicities presenting to the outpatient clinics. The overall frequency of G6PD deficiency by the FST was 13.7%. Among the deficient subjects, almost 90% had the Mahidol variant (487G>A) genotype. The remaining subjects had Chinese-4 (392G>T), Viangchan (871G>A), Açores (595A>G), Seattle (844G>C) and Mediterranean (563C>T) variants. Quantification of G6PD activity was performed using a modification of the standard spectrophotometric assay on a subset of 24 samples with Mahidol, Viangchan, Seattle and Chinese-4 mutations; all samples showed a residual enzymatic activity below 10% of normal and were diagnosed correctly by the FST. Further studies are needed to characterise the haemolytic risk of using 8-aminoquinolines in patients with these genotypes.
authors.affiliation: Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand.
authors.forename: Germana
authors.initials: G
authors.lastname: Bancone
authors.affiliation: Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand.
authors.forename: Cindy S
authors.initials: CS
authors.lastname: Chu
authors.affiliation: Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand.
authors.forename: Raweewan
authors.initials: R
authors.lastname: Somsakchaicharoen
authors.affiliation: Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand.
authors.forename: Nongnud
authors.initials: N
authors.lastname: Chowwiwat
authors.affiliation: Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand.
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Parker
authors.affiliation: Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
authors.forename: Prakaykaew
authors.initials: P
authors.lastname: Charunwatthana
authors.affiliation: Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: White
authors.affiliation: Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Thailand; Centre for Tropical Medicine, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
authors.forename: François H
authors.initials: FH
authors.lastname: Nosten
mesh_terms: D000293:Adolescent; D000328:Adult; D044466:Asian People / Q000235:genetics; D005260:Female; D005838:Genotype; D005954:Glucosephosphate Dehydrogenase / Q000235:genetics*; D005955:Glucosephosphate Dehydrogenase Deficiency / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D006801:Humans; D008288:Malaria / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics; D008297:Male; D010963:Plasmodium falciparum / Q000302:isolation & purification; D010966:Plasmodium vivax / Q000302:isolation & purification; D020641:Polymorphism, Single Nucleotide; D013785:Thailand / Q000453:epidemiology; D055815:Young Adult
chemical_list: D005954:Glucosephosphate Dehydrogenase