Abstract: Objective　To identify pathogenic gene mutations of glutaric aciduria typeⅠand provide genetic counseling and prenatal diagnosis for a Chinese family. Methods　Mutation of glutaryl-CoA dehydrogenase (GCDH) gene was detected in the proband with glutaric aciduria typeⅠby Ion Torrent semi-conductor sequencing for the screening of the pathogenic mutations. Both parents were verified by Sanger sequencing. Amniotic fluid fetal cells were extracted by amniocentesis at 18 weeks of gestation to detect GCDH gene. Results　The 4-year-old boy had pathogenic variations in the GCDH gene (NM_000159), including heterozygous mutations from the father c.395G>A (p.R132Q) and from the mother c.769C>T (p.R257W). The gene detection of amniotic fluid samples of the mother showed no mutation in c.395 and c.769 of GCDH gene, and there was no abnormality in the results of blood tandem mass spectrometry and growth in the neonate. Conclusions　The pathogenic mutation site of GCDH gene in a family of glutaric aciduria typeⅠwas successfully identified and prenatal molecular genetic diagnosis was provided to the mother of the child.

Key words: Ion torrent sequencing;　glutaric aciduria typeⅠ;　prenatal diagnosis