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Reviewed November 2013
What is the official name of the RHO gene?
The official name of this gene is “rhodopsin.”
RHO is the gene's official symbol. The RHO 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 RHO gene?
The RHO gene provides instructions for making a protein called rhodopsin. This protein is necessary for normal vision, particularly in low-light conditions. Rhodopsin is found in specialized light receptor cells called rods. As part of the light-sensitive tissue at the back of the eye (the retina), rods provide vision in low light. Other light receptor cells in the retina, called cones, are responsible for vision in bright light.
The rhodopsin protein is attached (bound) to a molecule called 11-cis retinal, which is a form of vitamin A. When light hits this molecule, it activates rhodopsin and sets off a series of chemical reactions that create electrical signals. These signals are transmitted to the brain, where they are interpreted as vision.
Does the RHO gene share characteristics with other genes?
The RHO gene belongs to a family of genes called GPCR (G protein-coupled receptors).
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 RHO gene related to health conditions?
Where is the RHO gene located?
Cytogenetic Location: 3q22.1
Molecular Location on chromosome 3: base pairs 129,528,639 to 129,535,344
(Homo sapiens Annotation Release 107, GRCh38.p2) (
The RHO gene is located on the long (q) arm of chromosome 3 at position 22.1.
More precisely, the RHO gene is located from base pair 129,528,639 to base pair 129,535,344 on chromosome 3.
See How do geneticists indicate the location of a gene? in the Handbook.
Where can I find additional information about RHO?
You and your healthcare professional may find the following resources about RHO 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 RHO 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 RHO?
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.