Coexistence of five G6PD variants indicates ethnic complexity of Phuket islanders, Southern Thailand

Abstract

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzymopathy in humans. The prevalence of G6PD deficiency and its molecular basis were studied in Phuket islanders, Southern Thailand. A total of 345 volunteers (123 males and 222 females) were recruited in this study. Infection with Plasmodium falciparum or Plasmodium vivax was not detected in any of these subjects by polymerase chain reaction (PCR)-based diagnosis. G6PD-deficient individuals were identified with the WST-8/1-methoxy PMS method. The molecular basis of G6PD deficiency was investigated by PCR-direct sequencing procedures or PCR-restriction enzyme fragment length polymorphism assays. The numbers of individuals showing severe and mild G6PD deficiency were 14 and 21, respectively. A high prevalence of G6PD deficiency was observed in subjects with Moken (15.4%) or Thai (15.5%) ethnic background. G6PD Mahidol (487G>A) (n=14), G6PD Viangchan (871G>A) (n=11), G6PD Gaohe (95A>G) (n=2), G6PD Kaiping (1388G>A) (n=1), and G6PD Kerala-Kalyan (949G>A) (n=1) were identified. The results suggest that several groups of people of the Asian Continent, such as Burmese, Laotian or Cambodian, Thai and Chinese, participated in the establishment of the ethnic identity of the current ethnic groups of Phuket Island.

Glucose-6-phosphate dehydrogenase mutations in Mon and Burmese of southern Myanmar

“…This mutation is also the second most common mutation in southern Thailand (Laosombat et al 2005). It is found in a few cases of Phuket Islanders in southern Thailand (Ninokata et al 2006) and a few cases of Malaysian Malay (Ainoon et al 2002). The haplotype of Chinese with G6PD Kaiping is also uniformly 1311C and 93T (Yan et al 2006), similar to our Mon case in this study.…”

“…G6PD Kerala-Kalyan (949G [ A) was reported to be prevalent (24.9%) in India (Sukumar et al 2004). None of these mutations were found in Thai, Laotians, or Cambodians, whereas G6PD Mediterranean was found in approximately 30% of G6PD-deficient Indonesians from central Java (Soemantri et al 1995), 27% of G6PD-deficient Malaysian Malays (Ainoon et al 2002), occasionally in Thais of the southern province of Thailand (Laosombat et al 2005), and G6PD KeralaKalyan was also identified in Urak-Lawoi, a sea Gypsy population of the Andaman Sea who inhabited Phuket Island in southern Thailand (Ninokata et al 2006). Both polymorphisms C and T are present at nt 1311 in Indians Numbers represent number of G6PD mutations identified.…”

“…For all unknown mutation samples, PCR direct sequencing was performed for each exon with primers in Table 1 (Nuchprayoon et al 2002;Huang et al 1996;Tang et al 1992;Ninokata et al 2006). For haplotype analysis, PCR-RFLP technique was performed for detecting nt1311C [ T polymorphism in exon 11 and nt93T [ C polymorphism in intron 11 (Vulliamy et al 1991;Beutler et al 1991).…”

Glucose-6-Phosphate Dehydrogenase Deficiency and Malaria: A Method to Detect Primaquine-Induced Hemolysis in vitro

“…In this study, it was suggested that the selective advantage of resistance to malaria was counterbalanced with selective disadvantageous results of G6PD deficiency, and this stopped the rise of malaria frequencies in endemic regions (Ruwende, et al, 1995). In another study, Ninokata et al (2006) investigated 345 healthy adults for G6PD deficiency on Phuket Island, which had been determined to be a malaria-endemic region and found out that 10% of these individuals had G6PD deficiency. Interestingly, it was observed that none of the individuals had molecular evidence of malaria infection.…”

“…Interestingly, it was observed that none of the individuals had molecular evidence of malaria infection. According to this study, researchers postulated that G6PD deficiency provided an advantageous genetic trait against malaria (Ninokata, et al, 2006).…”