[ASS1 mutation leading to citrullinemia I in a Chinese Han family].

To investigate potential mutation of the ASS1 gene in a male infant with acute citrullinemia type I.Genomic DNA was prepared from peripheral blood samples of the family members. Mutation analysis of the 14 ASS1 exons was carried out by PCR and direct DNA sequencing.A homozygous missense mutation of c.970G>A located in exon 13, which results in p.G324S, was identified in the child. Sequencing of the parents showed a heterozygous status for the same mutation.A missense mutation of c.970G>A in the ASS1 gene is responsible for the pathogenesis of the disease in the infant.