Defective MOGS causes CDG-2b

After the lipid-linked oligosaccharide (LLO) precursor is attached to the protein, the outer alpha-1,2-linked glucose is removed by by mannosyl-oligosaccharide glucosidase (MOGS). This is a mandatory step for protein folding control and glycan extension. Defects in MOGS are associated with congenital disorder of glycosylation type IIb (CDGIIb), a multisystem disorder caused by a defect in glycoprotein biosynthesis and characterised by under-glycosylated serum glycoproteins (De Praeter et al. 2000, Voelker et al. 2002). Type II CDGs refer to defects in the trimming and processing of protein-bound glycans.

Summary from Reactome (R-HSA-4793954), read 2026-09-23.