Objective: Citrullinemia type I (CTLN1) is an urea cycle defect caused by mutations in the argininosuccinate synthetase gene. We report the first identification in Argentina of patients with CTLN1 in a limited geographic area.
Design and methods: Molecular analysis in patient/relatives included PCR, sequencing and restriction enzyme assay.
Results: The studied families showed the same mutation: ASS~p.G390R, associated with the early-onset/severe phenotype.
Conclusion: We postulate a possible population cluster. A program to know the carrier frequency in that population is in progress.