Mannosidase Alpha Class 1B Member 1; Endoplasmic Reticulum Mannosyl-Oligosaccharide 1,2-Alpha-Mannosidase 1; Man9GlcNAc2-Specific Processing Alpha-Mannosidase; Endoplasmic Reticulum Class I Alpha-Mannosidase; ER Alpha 1,2-Mannosidase; ERMAN1; Endoplasmic Reticulum Mannosyl-Oligosaccharide 1,2-Alpha-Mannosidase; Man9GlcNAc2-Specific-Processing Alpha-Mannosidase; Endoplasmic Reticulum Alpha-Mannosidase 1

This gene encodes an enzyme belonging to the glycosyl hydrolase 47 family. This enzyme functions in N-glycan biosynthesis, and is a class I alpha-1,2-mannosidase that specifically converts Man9GlcNAc to Man8GlcNAc isomer B. It is required for N-glycan trimming to Man5-6GlcNAc2 in the endoplasmic-reticulum-associated degradation pathway. Mutations in this gene cause autosomal-recessive intellectual disability. Alternative splicing results in multiple transcript variants. A related pseudogene has been identified on chromosome 11.