A Novel A1088T Mutation in the Glucose-6-Phosphate Dehydrogenase Gene Detected by RT-PCR Combined with DNA Sequencing.

Abstract

Human glucose-6-phosphate dehydrogenase deficiency (G6PD) is mostly caused by single nucleotide change in the G6PD gene which leads to single amino acid substitution. Previous trials suggested a few samples had decreased ratio of G6PD/6PGD(<1.00) but no mutation detected by multiple methods. In 138 cases of Chinese children with G6PD deficiency, RT-PCR combined with DNA Sequencing was performed to screen the mutations in the coding region and promoter region of G6PD gene. The mutation detection frequency by this method was 100%, including a novel missense mutation (1088 A>T) and 13 mutations reported before. The novel mutation predicted an Asn-to-Ile substitution at codon 363, which was identified in a male infant patient. The variant caused by this mutation had reduced enzymatic activity, belonging to WHO Class I. Synonymous or missense mutation was not found in the proximalpromoter region of the G6PD gene, which was consistent with earlier findings that G6PD deficiency was not associated with promoter mutations in the G6PD gene. RT-PCR combined with DNA Sequencing could be another alternative for clinically molecular diagnosis of G6PD deficiency.