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Reviewed May 2014

What is the official name of the MAN2B1 gene?

The official name of this gene is “mannosidase, alpha, class 2B, member 1.”

MAN2B1 is the gene's official symbol. The MAN2B1 gene is also known by other names, listed below.

Read more about gene names and symbols on the About page.

What is the normal function of the MAN2B1 gene?

The MAN2B1 gene provides instructions for making the enzyme alpha-mannosidase. This enzyme works in the lysosomes, which are compartments that digest and recycle materials in the cell. Within lysosomes, the enzyme helps break down complexes of sugar molecules (oligosaccharides) attached to certain proteins (glycoproteins). In particular, alpha-mannosidase helps break down oligosaccharides containing a sugar molecule called mannose.

How are changes in the MAN2B1 gene related to health conditions?

alpha-mannosidosis - caused by mutations in the MAN2B1 gene

More than 120 mutations in the MAN2B1 gene have been identified in people with alpha-mannosidosis, a rare inherited disorder that causes problems in many organs and tissues of the body. Affected individuals may have intellectual disability, distinctive facial features, and skeletal abnormalities. Some of the MAN2B1 gene mutations that cause alpha-mannosidosis change one protein building block (amino acid) in the alpha-mannosidase enzyme. Other mutations result in an abnormally shortened enzyme, or cause the enzyme to be pieced together incorrectly.

These mutations interfere with the ability of the alpha-mannosidase enzyme to perform its role in breaking down mannose-containing oligosaccharides. These oligosaccharides accumulate in the lysosomes and cause the cells to malfunction and eventually die. Tissues and organs are damaged by the abnormal accumulation of oligosaccharides and the resulting cell death, leading to the characteristic features of alpha-mannosidosis.

Where is the MAN2B1 gene located?

Cytogenetic Location: 19p13.2

Molecular Location on chromosome 19: base pairs 12,646,508 to 12,666,777

(Homo sapiens Annotation Release 107, GRCh38.p2) (NCBIThis link leads to a site outside Genetics Home Reference.)

The MAN2B1 gene is located on the short (p) arm of chromosome 19 at position 13.2.

The MAN2B1 gene is located on the short (p) arm of chromosome 19 at position 13.2.

More precisely, the MAN2B1 gene is located from base pair 12,646,508 to base pair 12,666,777 on chromosome 19.

See How do geneticists indicate the location of a gene? in the Handbook.

Where can I find additional information about MAN2B1?

You and your healthcare professional may find the following resources about MAN2B1 helpful.

You may also be interested in these resources, which are designed for genetics professionals and researchers.

What other names do people use for the MAN2B1 gene or gene products?

  • lysosomal acid alpha-mannosidase
  • MANB
  • mannosidase, alpha B, lysosomal

Where can I find general information about genes?

The Handbook provides basic information about genetics in clear language.

These links provide additional genetics resources that may be useful.

What glossary definitions help with understanding MAN2B1?

amino acid ; cell ; class ; disability ; enzyme ; gene ; glycoproteins ; inherited ; mannose ; molecule ; oligosaccharides ; protein

You may find definitions for these and many other terms in the Genetics Home Reference Glossary.

See also Understanding Medical Terminology.

References (9 links)


The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? in the Handbook.

Reviewed: May 2014
Published: February 1, 2016