|A service of the U.S. National Library of Medicine®|
On this page:
Reviewed January 2014
What is the official name of the GJB4 gene?
The official name of this gene is “gap junction protein beta 4.”
GJB4 is the gene's official symbol. The GJB4 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 GJB4 gene?
The GJB4 gene provides instructions for making a protein called gap junction beta 4, more commonly known as connexin 30.3. This protein is part of the connexin family, a group of proteins that form channels called gap junctions on the surface of cells. Gap junctions open and close to regulate the flow of nutrients, charged atoms (ions), and other signaling molecules from one cell to another. They are essential for direct communication between neighboring cells.
Connexin 30.3 is found in several different tissues, including the outermost layer of the skin (the epidermis). This protein appears to play a role in the growth and maturation of epidermal cells.
Does the GJB4 gene share characteristics with other genes?
The GJB4 gene belongs to a family of genes called GJ (gap junction proteins (connexins)).
A gene family is a group of genes that share important characteristics. Classifying individual genes into families helps researchers describe how genes are related to each other. For more information, see What are gene families? in the Handbook.
How are changes in the GJB4 gene related to health conditions?
Where is the GJB4 gene located?
Cytogenetic Location: 1p34.3
Molecular Location on chromosome 1: base pairs 34,759,741 to 34,763,724
(Homo sapiens Annotation Release 107, GRCh38.p2) (
The GJB4 gene is located on the short (p) arm of chromosome 1 at position 34.3.
More precisely, the GJB4 gene is located from base pair 34,759,741 to base pair 34,763,724 on chromosome 1.
See How do geneticists indicate the location of a gene? in the Handbook.
Where can I find additional information about GJB4?
You and your healthcare professional may find the following resources about GJB4 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 GJB4 gene or gene products?
See How are genetic conditions and genes named? in the Handbook.
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 GJB4?
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
See also Understanding Medical Terminology.
References (6 links)