OBJECTIVETo develop and evaluate a simple, fast and accurate prenatal diagnosis method for glycogen storage disease Ia (GSD Ia) in Chinese.

METHODSThis study involved 3 unrelated families. Genomic DNA samples were extracted from the blood of three GSD Ia patients and their parents, from the amniocytes of 3 fetuses and the blood of 2 newborns. By the way of restriction enzyme analysis, the screening for 727G-->T and R83H mutations of glucose-6-phosphatase gene was carried out in conjunction with 1176 nucleotide polymorphism linkage analysis so as to make the gene and prenatal diagnosis of 3 GSD Ia families. Direct DNA sequencing of the corresponding PCR products was used to confirm the unveiled mutations and 1176 nucleotide polymorphism.

RESULTSThree probands were homozygotes for the 727G-->T mutation and their parents were heterozygotes for this mutation. The fetuses of family 1 and 3 were heterozygotes for the 727G-->T mutation, whereas the fetus of family 2 did not carry this mutation. The 1176 nucleotide polymorphisms of 3 fetuses were different from those of the corresponding probands. The prenatal diagnoses of family 1 and 2 were confirmed by the postnatal biochemical and molecular studies.

CONCLUSIONThese findings suggest that the screening for 727G-->T and R83H mutations in conjunction with the 1176 polymorphism linkage analysis be a simple, fast and accurate method for gene and prenatal diagnosis of GSD Ia in Chinese.