Citrullinemia is an autosomal recessive disease due to the mutations in the
argininosuccinate synthetase (ASS) gene. Mutation analysis was performed o
n three Korean patients with citrullinemia. AII of the three patients had t
he splicing mutation previously reported as IVS6-2A>G mutation. Two had Gly
324Ser mutation and the other patient had a 67-bp insertion mutation in exo
n 15, The IVS6-2A>G mutation was reported to be found frequently in Japanes
e patients with citrullinemia, but Caucasian patients showed the extreme mu
tational heterogeneity. Although a limited number of Korean patients were s
tudied, the IVS6-2A>G mutation appears to be one of the most frequent mutan
t alleles in Korean patients with citrullinemia, The Gly324Ser mutation ide
ntified in two patients also suggests the possible high frequency of this m
utation in Korean patients as well.