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Reviewed May 2014

What is the official name of the HPS1 gene?

The official name of this gene is “Hermansky-Pudlak syndrome 1.”

HPS1 is the gene's official symbol. The HPS1 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 HPS1 gene?

The HPS1 gene provides instructions for making a protein that forms part of a complex called biogenesis of lysosome-related organelles complex-3 (BLOC-3). This complex plays a role in the formation of a group of cellular structures called lysosome-related organelles (LROs). In particular, BLOC-3 helps turn on the process by which necessary proteins are transported to LROs during their formation. LROs are very similar to compartments within the cell called lysosomes, which digest and recycle materials. However, LROs perform specialized functions and are found only in certain cell types.

Within pigment-producing cells (melanocytes), LROs called melanosomes produce and distribute melanin, which is the substance that gives skin, hair, and eyes their color. A different type of LRO is found in platelets, the blood cells involved in normal blood clotting. These LROs, called dense granules, release chemical signals that cause platelets to stick together and form a blood clot. LROs are also found in other specialized cells, including certain cells of the lungs.

How are changes in the HPS1 gene related to health conditions?

Hermansky-Pudlak syndrome - caused by mutations in the HPS1 gene

At least 31 mutations in the HPS1 gene have been found to cause Hermansky-Pudlak syndrome type 1. Individuals with this form of the condition typically have oculocutaneous albinism, a condition characterized by fair skin, light-colored hair and eyes, and poor vision. They may also have bleeding problems and a severe lung disease called pulmonary fibrosis. The HPS1 gene mutations that cause Hermansky-Pudlak syndrome type 1 impair the normal function of BLOC-3, disrupting the size, structure, and function of LROs in cells throughout the body. The most common mutation causes a duplication of genetic material within the HPS1 gene and is found in people from northwest Puerto Rico. Specifically, this mutation results in an extra 16 DNA building blocks (nucleotides) within the gene (written as 1470_1486dup16).

Because the abnormal melanosomes do not distribute melanin properly, people with Hermansky-Pudlak syndrome have unusually light coloring of the skin, hair, and eyes. The absence of dense granules within platelets leads to bleeding problems in affected individuals. Pulmonary fibrosis may also develop due to abnormal LROs in certain lung cells.

Where is the HPS1 gene located?

Cytogenetic Location: 10q23.1-q23.3

Molecular Location on chromosome 10: base pairs 98,416,198 to 98,446,963

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

The HPS1 gene is located on the long (q) arm of chromosome 10 between positions 23.1 and 23.3.

The HPS1 gene is located on the long (q) arm of chromosome 10 between positions 23.1 and 23.3.

More precisely, the HPS1 gene is located from base pair 98,416,198 to base pair 98,446,963 on chromosome 10.

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

Where can I find additional information about HPS1?

You and your healthcare professional may find the following resources about HPS1 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 HPS1 gene or gene products?

  • Hermansky-Pudlak syndrome 1 protein
  • Hermansky-Pudlak syndrome 1 protein isoform a
  • Hermansky-Pudlak syndrome 1 protein isoform c
  • Hermansky-Pudlak syndrome type 1
  • HPS
  • MGC5277

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 HPS1?

albinism ; blood clotting ; cell ; clotting ; DNA ; duplication ; fibrosis ; gene ; guanine ; lysosome ; melanin ; melanocytes ; mutation ; nucleotide ; pigment ; platelets ; protein ; pulmonary ; syndrome

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

See also Understanding Medical Terminology.

References (11 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