Molecular genetics of citrullinemia types I and II

• Numerous studies have investigated mutations in the ASS1 and SLC25A13 genes.
• Our study is a review article about the mutations and genotype–phenotype correlations of these genes.
• Confounding factors other than genetic mutations may influence phenotypes.
• Some mutations of these genes seem to be related to specific phenotypes.

Over the past decade, the ASS1 and SLC25A13 genes, which are responsible for citrullinemia types I and II, have been identified, and numerous mutations in these genes have been reported. The clinical manifestations of citrullinemia are quite heterogeneous, and most studies have reported mutations in a small number of patients from a few families. Comprehensive integration of previous knowledge is important to understand the mutation spectrum and effect of the mutations on clinical manifestations. Therefore, we reviewed the English literature on mutations in the ASS and SLC25A13 genes, and their genotype–phenotype correlations to provide valuable insights into the molecular genetic background of citrullinemia types I and II.