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GRN

GRN

Reviewed September 2010

What is the official name of the GRN gene?

The official name of this gene is “granulin.”

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

The GRN gene provides instructions for making a protein called granulin (also known as progranulin). This protein is found in tissues throughout the body. It is most active in cells that are dividing rapidly, such as skin cells and cells that line the gastrointestinal tract. Granulin helps regulate the growth, division, and survival of these cells. It also plays important roles in early embryonic development, regulation of the body's immune system response, and wound healing.

Granulin is active in several types of brain cells, although much less is known about this protein's function in the brain. It appears to be critical for the survival of nerve cells (neurons).

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

GRN-related frontotemporal dementia - associated with the GRN gene

More than 65 mutations in the GRN gene have been identified in people with GRN-related frontotemporal dementia. The most common mutation, which is written as Arg493Ter or R493X, creates a premature stop signal in the instructions for making granulin. Most of the mutations that cause GRN-related frontotemporal dementia prevent any protein from being produced from one copy of the GRN gene in each cell. As a result of these genetic changes, cells make only half the usual amount of granulin.

It is unclear how a shortage of granulin leads to the features of GRN-related frontotemporal dementia. However, studies have shown that the disorder is characterized by the buildup of a protein called TAR DNA-binding protein (TDP-43) in certain brain cells. The TDP-43 protein forms clumps (aggregates) that may interfere with cell functions and ultimately lead to cell death. Researchers are working to determine how mutations in the GRN gene, and the resulting loss of granulin, are related to a buildup of TDP-43 in the brain.

The features of GRN-related frontotemporal dementia result from the gradual loss of neurons in regions near the front of the brain called the frontal and temporal lobes. The frontal lobes are involved in reasoning, planning, judgment, and problem-solving, while the temporal lobes help process hearing, speech, memory, and emotion. The death of neurons in these areas causes problems with many critical brain functions. However, it is unclear why the loss of neurons occurs in the frontal and temporal lobes more often than other brain regions in people with GRN-related frontotemporal dementia.

Where is the GRN gene located?

Cytogenetic Location: 17q21.32

Molecular Location on chromosome 17: base pairs 44,345,122 to 44,353,105

The GRN gene is located on the long (q) arm of chromosome 17 at position 21.32.

The GRN gene is located on the long (q) arm of chromosome 17 at position 21.32.

More precisely, the GRN gene is located from base pair 44,345,122 to base pair 44,353,105 on chromosome 17.

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

Where can I find additional information about GRN?

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

  • acrogranin
  • CLN11
  • GEP
  • GP88
  • granulin-epithelin
  • granulins
  • granulins precursor
  • GRN_HUMAN
  • PC cell-derived growth factor
  • PCDGF
  • PEPI
  • PGRN
  • proepithelin
  • progranulin

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 GRN?

cell ; dementia ; DNA ; embryonic ; gastrointestinal ; gene ; growth factor ; immune system ; mutation ; precursor ; protein

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

See also Understanding Medical Terminology.

References (10 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: September 2010
Published: October 27, 2014