Disorders Affecting Glycosylation

Glycosylation is the cellular metabolic process of adding sugar chains (glycans) to proteins and lipids. These complex post-translational modifications occur in all cells generating thousands of glycan structures through nine major pathways. Mutations have been found in about 140 of the estimated 400 genes that produce or recognize glycans. In this chapter, we present a genetic, clinical and biochemical overview of selected congenital disorders of glycosylation (CDG). Clinically, most types of CDG have multi-systemic, especially neurological, presentations. Inheritance is mostly autosomal recessive, but de novo, X-linked, and dominant CDGs are appearing. Therapies are few, but simple monosaccharide supplements can be useful.