Methylmalonate Semialdehyde Dehydrogenase Deficiency

Methylmalonate Semialdehyde Dehydrogenase Deficiency (MMSDH Deficiency; Aldehyde Dehydrogenase 6 Family, Member A1; ALDH6A1 Deficiency)is caused by a defect in methylmalonate semialdehyde dehydrogenase, which catalyzes the irreversible oxidative decarboxylation of malonate and methylmalonate semialdehydes to acetyl- and propionyl-CoA, respectively. A defect in methylmalonate semialdehyde dehydrogenase causes accumulation of 3-Aminoisobutyric acid, 3-Hydroxyisobutyric acid, 3-hydroxypropionic acid, beta-Alanine, lactate, and methylmalonic acid in urine. Symptoms inclue failure to thrive, large liver, mental and motor retardation and vomiting.

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  1. OMIM: Entry 603178
  2. Chambliss KL, Gray RG, Rylance G, Pollitt RJ, Gibson KM: Molecular characterization of methylmalonate semialdehyde dehydrogenase deficiency. J Inherit Metab Dis. 2000 Jul;23(5):497-504. Pubmed
  3. Kedishvili NY, Popov KM, Rougraff PM, Zhao Y, Crabb DW, Harris RA: CoA-dependent methylmalonate-semialdehyde dehydrogenase, a unique member of the aldehyde dehydrogenase superfamily. cDNA cloning, evolutionary relationships, and tissue distribution. J Biol Chem. 1992 Sep 25;267(27):19724-9. Pubmed