Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Since the original description 26 years ago, of the hepatic glycogen synthetase deficiency, only one more case was reported in 1977. We present the studies carried out on an Argentine boy of Italian ancestry who at age 21 months, showed signs of hepatic deficiency with mild clinical symptoms which contrasted with a remarkable fatty liver degeneration. A totally atypic reaction to fructose overload (Table 1, Fig. 1) was the first key to the diagnosis. Glucose levels were not significantly modified by glucagon after 12-hours fasting, but it did increase the glycemia, with decrease of lactate and alanine 3 hours after-meal (Fig. 2a, b). The 24-hours metabolic profile showed fasting hypoglycemia, hyperketonemia, low alanine concentrations and mild lactatemia and hyperglycemia and a net post-prandial increase of lactate (Fig. 3). This profile when reduced to 14 hours, 12-fasting hours and 2-postprandial hours (Fig. 4), revealed similar alterations in an asymptomatic younger brother. The development of the investigation led to a second hepatic biopsy which confirmed hepatic steatosis and to an ultrastructural study, which showed subcellular alterations in the liver and also in muscle (Fig. 5). Moreover low content of hepatic glycogen was observed along with glycogen synthetase activity between 20-25% that of controls, being normal the enzyme activity in muscle and fibroblasts cultured from a skin biopsy (Table 2). The clinical pattern mainly without hypoglycemia, convulsions and/or mental retardation and a normal height and body mass development, allowed us to postulate that this Argentine report would be a mild variant of the disease formerly described and would be correlated with a partial deficiency of the hepatic glycogen synthetase.
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PMID:[Hepatic glycogen synthetase deficiency or glycogen storage disease-zero. Mild phenotype with partial enzymatic defect]. 213 Feb 23

Fragile-X-syndrome (FXS) is the most common type of inherited cognitive impairment. The underlying molecular alteration consists of a CGG-repeat amplification within the FMR-1 gene. The phenotype is only apparent once a threshold in the number of repeats has been exceeded (full mutation). The aim of this study was to characterize the FMR-1 CGG-repeat status in Argentine patients exhibiting mental retardation. A total of 330 blood samples from patients were analyzed by PCR and Southern blot analysis. Initially, DNA from 78 affected individuals were studied by PCR. Since this method is unable to detect high molecular weight alleles, however, we undertook a second approach using the Southern blotting technique to analyze the CGG repeat number and methylation status. Southern blot analysis showed an altered pattern in 14 out of 240 (6%) unrelated patients, with half of them presenting a mosaic pattern. Eight out of 17 families (47%) showed a (suggest deleting highlight). The characteristic FXS pattern was identified in 8/17 families (47%), and in 4 of these families 25% of the individuals presented with a mosaic model. The expansion from pre-mutation to full mutation was shown to occur both at the pre and post zygotic levels. The detection of FXS mutations has allowed us to offer more informed genetic counseling, prenatal diagnosis and reliable patient follow-up.
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PMID:Fragile-X mental retardation: molecular diagnosis in Argentine patients. 1712 14