Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038379 (strabismus)
 9,317 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Carbohydrate-deficient glycoprotein syndrome type 1 (CDGS-1) is an autosomal recessive hereditary metabolic disorder, the gene locus of which is chromosome 16p13. The disorder is characterised by genetic heterogeneity, and by decrease in the gene product, phosphomannomutase 2, though the heterogeneity is far less manifest in affected Swedish families. Its incidence is 1/80,000 live births, and the under-5 mortality rate over 30 per cent. The causes of death are liver failure, cardiac tamponade, haemorrhaging, and severe infection. The characteristic biochemical aberration is the occurrence of deficient carbohydrate chains in many but not all circulating glycoproteins, and the serum and blood concentrations of some glycoproteins may be above or below normal. These changes may improve over time, but never normalise. The clinical picture is generally more problematic during the first years of life when psychomotor retardation is complicated by failure to thrive, liver dysfunction, pericardial effusions, and stroke-like episodes. In addition, strabismus, lipocutaneous anomalies, and gluteal fat pads are always present, and muscular hypotonia and restricted joint mobility are common. Failure to thrive is common, with vomiting and diarrhoea and subsequent slow growth. Inflammation is a constant finding in the liver, and very common in the small bowel. Pancreatic function is also affected. Pericardial effusion has been reported in 50 per cent of the youngest children, requiring pericardectomy in 30 per cent of cases. Haemorrhaging and thromboembolic complications may occur, and the serum concentrations of several factors and inhibitors are low, particularly those of factors V and XI, protein C and antithrombin. Stroke-like episodes occur in about 30 per cent of cases, often following an infection, with coma lasting for hours to several days. Such sequelae as hemiplegia, blindness, and other focal neurological pathology have been observed transiently. Diagnosis is based on the serum carbohydrate-deficient transferrin level, verified by isoelectric focusing. Molecular genetic procedures enable point mutations to be identified and prenatal diagnosis to be performed in many families.
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PMID:[CDGS-1--a recently discovered hereditary metabolic disease. Multiple organ manifestations, incidence 1/80,000, difficult to treat]. 988 93

Congenital disorders of glycosylation (CDG) are genetic diseases due to defects in the synthesis or the attachment of the glycan moiety of glycoproteins and glycolipids. They can be divided into four groups: disorders of protein N-glycosylation, disorders of protein O-glycosylation, disorders of lipid glycosylation, and disorders of other glycosylation pathways and of multiple glycosylation pathways. Of the more than 40 reported CDG, some 80% are neurological or have an important neurological component. By far the most common neurological CDG is phosphomannomutase 2 deficiency. Isoelectrofocusing of serum transferrin, the most widely used screening test, picks up only CDG associated with sialic acid deficiency of N-linked glycans. Predominant neurological signs and symptoms are psychomotor retardation, epilepsy, hypotonia, hyporeflexia, strabismus, retinitis pigmentosa, polyneuropathy, myopathy, and cerebellar hypotrophy/hypoplasia. All known neurological CDG have an autosomal recessive inheritance except for IAP-CDG, an X-linked pure mental retardation syndrome. No curative or effective treatment is available for neurological CDG. Since at least 1% of the genome is involved in glycosylation, it is likely that the large majority of CDG is yet to be discovered. In 2008, a novel nomenclature was introduced using the gene symbol followed by -CDG, e.g., CDG-Ia becomes PMM2-CDG. CDG should be looked for in any unexplained neurological syndrome.
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PMID:Congenital disorders of glycosylation. 2362 97

Aims: To describe the evolution of ophthalmological and electrophysiological findings in monozygotic twin sisters with phosphomannomutase 2 deficiency (PMM2-CDG). Methods: A clinical ophthalmological examination with visual acuity measurement, fundoscopy and flash electroretinogram (fERG) was performed at the age of 4, 18 and 41 years. Results: Ophthalmic examination in both girls at the age of 4 years showed an alternating convergent squint and a saccadic pursuit, with visual acuity of 6/9 in both eyes (Ffooks symbols test). Fundoscopy revealed a normal aspect of the optic discs, narrowed blood vessels and a mild irregular pigmentation in the peripheral retina. Flash ERG in one girl showed a recognisable a, b1 and b2 wave, but with a reduction of the amplitude to less than 40% of the normal amplitude. In the other twin girl, the amplitude was more reduced, but a small b1 wave for the white flash was still noticeable. At the age of 18 years, vision had remained stable. Fundus examination revealed a pink aspect of the optic discs, with moderately narrowing of the vasculature and bone spicules in the mid peripheral retina. fERG showed obvious progression with a completely extinguished trace bilaterally. At the age of 41 years, vision had slightly diminished to 6/12 in both women. Fundoscopy and electroretinogram did not show any changes. Conclusions: Despite obvious deterioration of the fERG between the age of 4 and 18 years, the central vision showed only a minor decrease between the age of 18 and 41 years with still a good functional visual acuity.
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PMID:Ophthalmological and electrophysiological findings in monozygotic twin sisters with phosphomannomutase 2 deficiency (PMM2-CDG) over a period of 37 years. 3180 66