title: Generation of a mouse model for citrullinemia by targeted disruption of the argininosuccinate synthetase gene.
abstract: Argininosuccinate synthetase (ASS) is a urea cycle enzyme that forms argininosuccinate from citrulline and aspartate. Mutations at the ASS locus in man cause the inherited disease, citrullinemia. Citrullinemia is inherited as an autosomal recessive trait and is characterized, biochemically, by elevated levels of blood citrulline and ammonia and often results in early neonatal death if untreated. We have used homologous recombination in embryonic stem cells to generate a line of mice having a targeted disruption of the Ass gene. Homozygous mutant animals develop high levels of blood citrulline, become hyperammonemic, and die within one or two days after birth. Because the phenotype of the mutant mice closely resembles that of humans who lack the ASS enzyme, we expect that these mice will serve as a useful model for exploring new treatments for citrullinemia including somatic gene therapy.
authors.affiliation: Institute for Molecular Genetics, Baylor College of Medicine, Houston, Texas 77030.
authors.forename: G
authors.initials: G
authors.lastname: Patejunas
authors.forename: A
authors.initials: A
authors.lastname: Bradley
authors.forename: A L
authors.initials: AL
authors.lastname: Beaudet
authors.forename: W E
authors.initials: WE
authors.lastname: O'Brien
mesh_terms: D000592:Amino Acid Metabolism, Inborn Errors / Q000235:genetics*; D000596:Amino Acids / Q000097:blood; D000641:Ammonia / Q000097:blood; D000818:Animals; D001124:Argininosuccinate Synthase / Q000235:genetics*; D002478:Cells, Cultured; D002956:Citrulline / Q000097:blood*; D004195:Disease Models, Animal; D006579:Heterozygote; D006720:Homozygote; D051379:Mice; D008807:Mice, Inbred BALB C; D008817:Mice, Mutant Strains; D010957:Plasmids; D011995:Recombination, Genetic; D013234:Stem Cells
chemical_list: D000596:Amino Acids; D002956:Citrulline; D000641:Ammonia; D001124:Argininosuccinate Synthase