OBJECTIVETo analyze the clinical features, metabolic profiling and gene mutations of patients with ornithine transcarbamylase deficiency (OTCD) and explore the molecular pathogenesis of OTCD in order to provide a solution for molecular diagnostics and genetic counseling.

METHODSClinical data of 3 neonates were analyzed. The amino acids level in blood was analyzed with mass spectrum technology. PCR was used to amplify all the 10 exons of OTC gene. The PCR products were directly sequenced to detect the mutations.

RESULTSAll of the 3 cases had neonatal onset and showed poor reaction, feeding difficulty, convulsion and neonatal infection. Citrulline levels were significantly decreased. Case 1 had a missense mutation of Y183C. Case 2 showed a missense mutation of V339G in exon 10. And a missense mutations of W332S in exon 9 was detected in case 3.

CONCLUSIONAnalysis of OTC gene sequences can be used for the diagnosis of OTCD and screening of asymptomatic carriers. Mutation analysis is important for prenatal diagnosis of individuals with a positive family history and genetic counseling. The V339G and W332S mutations have been discovered for the first time. Patients with such mutations may have onset of the disease during neonatal period.