Stockler, SylviaSylviaStocklerIsbrandt, DirkDirkIsbrandtHanefeld, FolkerFolkerHanefeldSchmidt, BernhardBernhardSchmidtFigura, Kurt vonKurt vonFigura2019-07-102019-07-101996https://resolver.sub.uni-goettingen.de/purl?gro-2/61031In two children with an accumulation of guanidinoacetate in brain and a deficiency of creatine in blood, a severe deficiency of guanidinoacetate methyltransferase (GAMT) activity was detected in the liver. Two mutant GAMT alleles were identified that carried a single base substitution within a 5' splice site or a 13-nt insertion and gave rise to four mutant transcripts. Three of the transcripts encode truncated polypeptides that lack a residue known to be critical for catalytic activity of GAMT. Deficiency of GAMT is the first inborn error of creatine metabolism. It causes a severe developmental delay and extrapyramidal symptoms in early infancy and is treatable by oral substitution with creatine.application/pdfenGoescholarhttps://goescholar.uni-goettingen.de/licenseGuanidinoacetate methyltransferase deficiency610journal_articlehttps://resolver.sub.uni-goettingen.de/purl?goescholar/3442openAccess