title: Liver-specific glucose-6-phosphatase is not present in human placenta.
abstract: Type I glycogen storage disease (McKusick 23220), an inherited absence or deficiency of glucose-6-phosphatase (EC 3.1.3.9) activity in the liver, kidney and intestine, is associated with the accumulation of glycogen in those organs. Previous reports have shown that glucose-6-phosphatase exists in human placenta and that detection of a heterozygote for this disorder from placenta might be possible. Our finding of a normal glucose-6-phosphatase activity in a placenta from a patient at risk for type Ia glycogen storage disease prompted us to examine in more detail placental glucose-6-phosphatase. Unexpectedly, we found the properties of the placental enzyme differed from that in normal liver, and the placental enzyme hydrolyzed glucose-6-phosphate, mannose-6-phosphate, beta-glycerol phosphate and glucose-1-phosphate equally well. Our data suggest the enzyme deficient in type I glycogen storage disease cannot be detected in placenta.
mesh_terms: D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis; D005952:Glucose-6-Phosphatase / Q000032:analysis* / Q000302:isolation & purification; D005953:Glycogen Storage Disease Type I / Q000175:diagnosis / Q000235:genetics*; D006801:Humans; D008099:Liver / Q000201:enzymology*; D010920:Placenta / Q000201:enzymology*; D011247:Pregnancy; D011296:Prenatal Diagnosis
chemical_list: D005952:Glucose-6-Phosphatase