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Reviewed December 2008

What is the official name of the IDS gene?

The official name of this gene is “iduronate 2-sulfatase.”

IDS is the gene's official symbol. The IDS 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 IDS gene?

The IDS gene provides instructions for producing an enzyme called iduronate 2-sulfatase (I2S), which is essential for the breakdown of large sugar molecules called glycosaminoglycans (GAGs). Specifically, I2S removes a chemical group known as a sulfate from a molecule called sulfated alpha-L-iduronic acid, which is present in two GAGs called heparan sulfate and dermatan sulfate. I2S is located in lysosomes, compartments within cells that digest and recycle different types of molecules.

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

mucopolysaccharidosis type II - caused by mutations in the IDS gene

More than 300 mutations in the IDS gene have been found to cause mucopolysaccharidosis type II (MPS II). Mutations that change one DNA building block (nucleotide) are the most common. All mutations that cause MPS II reduce or completely eliminate the function of I2S. It usually cannot be determined whether a certain mutation will cause severe or mild MPS II; however, mutations that result in the complete absence of I2S cause the more severe form of the disorder.

Lack of I2S enzyme activity leads to the accumulation of heparan sulfate and dermatan sulfate within cells, specifically inside the lysosomes. The buildup of these GAGs increases the size of the lysosomes, which is why many tissues and organs are enlarged in MPS II. Researchers believe that the accumulated GAGs may also interfere with the functions of other proteins inside the lysosomes and disrupt the movement of molecules inside the cell.

Where is the IDS gene located?

Cytogenetic Location: Xq28

Molecular Location on the X chromosome: base pairs 149,478,764 to 149,505,354

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

The IDS gene is located on the long (q) arm of the X chromosome at position 28.

The IDS gene is located on the long (q) arm of the X chromosome at position 28.

More precisely, the IDS gene is located from base pair 149,478,764 to base pair 149,505,354 on the X chromosome.

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

Where can I find additional information about IDS?

You and your healthcare professional may find the following resources about IDS 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 IDS gene or gene products?

  • iduronate-2-sulfatase
  • iduronate 2-sulfatase (Hunter syndrome)

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 IDS?

breakdown ; cell ; DNA ; enzyme ; gene ; heparan sulfate ; molecule ; mutation ; nucleotide ; sulfate ; syndrome

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

See also Understanding Medical Terminology.

References (6 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: December 2008
Published: February 1, 2016