Prediction of functional consequences of the five newly discovered G6PD variations in Taiwan

Glucose-6-phosphate dehydrogenase deficiency (G6PD deficiency; OMIM #300908) is the most common inborn error disorders worldwide. While the G6PD is the key enzyme of removing oxidative stress in erythrocytes, the early diagnosis is utmost vital to prevent chronic and drug-, food- or infection-induced hemolytic anemia. The characterization of the mutations is also important for the subsequent genetic counseling, especially for female carrier with ambiguous enzyme activities and males with mild mutations. While multiplex SNaPshot assay and Sanger sequencing were performed on 500 G6PD deficient males, five newly discovered variations, namely c.187G > A (p.E63K), c.585G > C (p.Q195H), c.586A > T (p.I196F), c.743G > A (p.G248D), and c.1330G > A (p.V444I) were detected in the other six patients. These variants were previously named as the Pingtung, Tainan, Changhua, Chiayi, and Tainan-2 variants, respectively. The in silico analysis, as well as the prediction of the structure of the resultant mutant G6PD protein indicated that these five newly discovered variants might be disease causing mutations.