MAN2B2 is a 1,009 amino acid secreted protein that belongs to the glycosyl hydrolase 38 family. Expressed as multiple alternatively spliced isoforms, MAN2B2 uses zinc as a cofactor to catalyze the hydrolysis of terminal, non-reducing alpha-D-mannose residues in alpha-D-mannoside proteins. The gene encoding MAN2B2 maps to human chromosome 4, which encodes nearly 6% of the human genome and has the largest gene deserts (regions of the genome with no protein encoding genes) of all of the human chromosomes. Defects in some of the genes located on chromosome 4 are associated with Huntington's disease, Ellis-van Creveld syndrome, methylmalonic acidemia and polycystic kidney disease.