CDG due to Defective Membrane Transporters: Update.

Congenital disorders of glycosylation are genetic defects in the glycoprotein and glycolipid glycan assembly and attachment. Some 200 CDG have been reported since the first clinical description in 1980. Most CDG are enzymatic deficiencies, but 13 (6.5%) are defects in the ER, Golgi apparatus (GA), and plasma membrane transporters. This review provides an update on the clinical, biochemical, genetic, and therapeutic aspects of these disorders and on animal models. Defects in other cellular trafficking mechanisms have been excluded from this update.