[Congenital disorders of glycosylation].

Abstract

Congenital disorders of glycosylation (CDG) is a fast growing group of autosomal recessive inherited diseases caused by defects in glycosylation. The biosynthesis of the glycans is a pathways which occurs in the endoplasmic reticulum and Golgi complex thanks to highly specific enzymes: glycosidases and glycosyltransferases. The sequential addition of monosaccharides needs precursors which are nucleotide sugars or dolichyl sugars. CDG are divided into two groups: CDG I composed of defects in enzymes involved in the assembly of dolicholpyrophosphate oligosaccharide and in the transfer of oligosaccharide from dolicholpyrophosphate to an Asn residue on nascent proteins; CDG II composed of defects in the processing of protein-bound glycans with alterations in enzymes or in the transporters of monosaccharides. Clinical symptoms are poorly specific and multisystemic, biochemistry provides the diagnosis: Isoelectrofocalisation and western blot of serum transferrin and some other glycoproteins; Measurement of enzyme activities; Research of gene mutations. Today, thirteen CDG are identified, the most frequent is CDG Ia due to a defect in the phosphomannomutase activities and CDG Ib due to a defective phosphomannose isomerase, is the only CDG which is successfully treated with mannose.

• Authors: G Durand, Th Dupré, S Vuillaumier-Barrot, N Seta
• Journal: Annales pharmaceutiques francaises (Ann Pharm Fr) Vol. 61 Issue 5 Pg. 330-9 ( 2003) ISSN: 0003-4509 [Print] France
• Vernacular Title: Etude des anomalies congénitales de la glycosylation.
• PMID: 13130291 (Publication Type: English Abstract, Journal Article, Review)

Chemical References

• Glycoproteins

Topics

• Carbohydrate Metabolism, Inborn Errors (enzymology, genetics)
• Glycoproteins (genetics, metabolism)
• Glycosylation
• Humans
• Mutation (genetics)