Brief communication (Original). Molecular characterization of G6PD mutations in the Phuan tribe in Thailand

Background: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an enzymopathy with high frequency in Southeast Asians. Phuan is a minority tribe in Thailand. The prevalence of G6PD deficiency and its molecular heterogeneity in this population is yet unknown.

Objectives: To characterize molecular heterogeneity of G6PD in Phuan people and investigate whether the heterogeneity of G6PD could be used to delineate the origin of Phuan people in Thailand.

Methods: Cord blood samples from 202 Phuan neonates were tested for G6PD deficiency using a G6PD activity assay. G6PD mutations were determined in G6PD deficient blood samples by polymerase chain reaction-restriction fragment length polymorphism analysis and sequencing.

Results: G6PD deficiency was found in 12 (12.2%) of 98 males and 8 (7.7%) of 104 females in the study population. Molecular analysis was performed on 12 males and 8 females to identify G6PD mutations. G6PD Viangchan (871G→A, 1311C→T)(25.0%) was the most dominant mutation followed by the G6PD Canton (1376G→T) (15.0%), G6PD Union (1360C→T) (10.0%), one case each of G6PD Kaiping (1388G→A) and G6PD Mediterranean (563C→T, 1311C) (5%), and eight G6PD deficient unidentified mutations.

Conclusions: G6PD deficiency in Phuan is highly frequent and G6PD Viangchan(871G→A, 1311C→T) is the most common mutation. Our study suggests that Phuans have coevolved with Thais, and were influenced by gene flow from Chinese and Indian mutations.