描述
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.