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Reviewed July 2012
What is the official name of the ABCB4 gene?
The official name of this gene is “ATP binding cassette subfamily B member 4.”
ABCB4 is the gene's official symbol. The ABCB4 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 ABCB4 gene?
The ABCB4 gene (also known as MDR3) provides instructions for making a protein that helps move certain fats called phospholipids across the membranes of liver cells and release the phospholipids into a digestive fluid called bile. Outside the liver cells, phospholipids attach (bind) to bile acids, which are a component of bile that digest fats. Large amounts of bile acids are potentially harmful to cells; when they are bound to phospholipids, bile acids are less toxic.
Does the ABCB4 gene share characteristics with other genes?
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 ABCB4 gene related to health conditions?
Where is the ABCB4 gene located?
Cytogenetic Location: 7q21.1
Molecular Location on chromosome 7: base pairs 87,402,044 to 87,477,523
(Homo sapiens Annotation Release 107, GRCh38.p2) (
The ABCB4 gene is located on the long (q) arm of chromosome 7 at position 21.1.
More precisely, the ABCB4 gene is located from base pair 87,402,044 to base pair 87,477,523 on chromosome 7.
See How do geneticists indicate the location of a gene? in the Handbook.
Where can I find additional information about ABCB4?
You and your healthcare professional may find the following resources about ABCB4 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 ABCB4 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 ABCB4?
acids ; ATP ; bile ; calcium ; cell ; cholesterol ; digestive ; familial ; fever ; gallbladder ; gene ; inflammation ; liver failure ; mutation ; pancreas ; pancreatitis ; phospholipid ; phospholipids ; protein ; secretion ; toxic
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
See also Understanding Medical Terminology.
References (13 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.