title: [A new family with mutation of the structural gene of human ornithine carbamoyltransferase].
abstract: Studies of a child with hyperammonemia have demonstrated a deficiency in OCTase. The kinetic properties of the enzyme were studied and it could be shown that we have to deal with a new mutation which is different from the ones previously known. It is a mutation of the structural gene. The detection of a heterozygote is possible when the urinary orotic acid excretion is studied after a loading meal (2g of proteines per kilo of weight). A child with hyperammonaemia due to ornithine transcarbamylase deficiency is described. A new structural gene mutation is probable because the kinetic properties of the enzyme are different to previously described variants. The heterozygote could be detected by the measurement of the excretion of orotic acid in the urine following a protein load of 2 g/Kg.
mesh_terms: D000592:Amino Acid Metabolism, Inborn Errors / Q000235:genetics*; D000641:Ammonia / Q000097:blood*; D005796:Genes; D006579:Heterozygote; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D009154:Mutation; D009954:Ornithine Carbamoyltransferase / Q000235:genetics; D020163:Ornithine Carbamoyltransferase Deficiency Disease; D009963:Orotic Acid / Q000652:urine; D010375:Pedigree
chemical_list: D009963:Orotic Acid; D000641:Ammonia; D009954:Ornithine Carbamoyltransferase
vernacular_title: Une nouvelle famille avec mutation du gène de structure de l'ornithine carbamyltransférase humaine.