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Reviewed January 2009
What is the official name of the TTR gene?
The official name of this gene is “transthyretin.”
TTR is the gene's official symbol. The TTR 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 TTR gene?
The TTR gene provides instructions for producing a protein called transthyretin. This protein transports vitamin A (retinol) and a hormone called thyroxine throughout the body. To transport thyroxine, four transthyretin proteins must be attached (bound) to each other to form a four-protein unit (tetramer). To transport retinol, transthyretin must form a tetramer and also bind to retinol binding protein. Transthyretin is produced primarily in the liver. A small amount of this protein is produced in an area of the brain called the choroid plexus and in the light-sensitive tissue that lines the back of the eye (the retina).
How are changes in the TTR gene related to health conditions?
Where is the TTR gene located?
Cytogenetic Location: 18q12.1
Molecular Location on chromosome 18: base pairs 31,591,767 to 31,599,024
(Homo sapiens Annotation Release 107, GRCh38.p2) (
The TTR gene is located on the long (q) arm of chromosome 18 at position 12.1.
More precisely, the TTR gene is located from base pair 31,591,767 to base pair 31,599,024 on chromosome 18.
See How do geneticists indicate the location of a gene? in the Handbook.
Where can I find additional information about TTR?
You and your healthcare professional may find the following resources about TTR 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 TTR 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 TTR?
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
See also Understanding Medical Terminology.
References (7 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.