Carbohydrate deficient glycoprotein (CDG) syndrome type I.

Abstract

CDG syndrome type I is a genetic, mul- tisystemic disorder characterised by a partial deficiency of the N-linked glycans of secretory glycoproteins, lysosomal enzymes, and probably also membranous glycoproteins. The first patients were reported in 1980.' The basic defect was elucidated only in 1995 as a phosphomannomutase deficiency.2 As of February 1996 some 200 patients worldwide (published and unpublished) were known to the authors. Since the N-linked glycoproteins play im- portant roles in every organ and biochemical system of the body, it is no wonder that this syndrome is one of the most complex metabolic diseases known, with an extremely broad bio- chemical as well as clinical spectrum.3-