OPN1MW: Medium-Wavelength-Sensitive Opsin
Green Cone Pigment Gene – Color Vision and X-Linked Retinal Disorders
Gene Information Card
| Symbol | OPN1MW |
|---|---|
| Full Name | Opsin 1, medium wave sensitive |
| Gene Type | Protein coding |
| Chromosomal Location | Xq28 |
| NCBI Gene ID | 2652 ncbi.nlm.nih.gov/gene/2652 |
| Ensembl ID | ENSG00000102076 |
| UniProt ID | P04001 |
| OMIM ID | 300821 |
| HGNC ID | 8140 |
| Aliases | CBBM, COD5, GCP, GOP, M-opsin, green cone pigment |
Description
OPN1MW encodes the medium-wavelength-sensitive opsin (M-opsin), a G-protein-coupled receptor expressed in cone photoreceptor cells of the retina. This pigment is maximally sensitive to green light (~530 nm). Mutations in OPN1MW cause X-linked color vision deficiencies, including deuteranopia, deuteranomaly, and blue cone monochromacy. The gene is located in a tandem array on Xq28 with OPN1LW (long-wavelength opsin).
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Deuteranopia (green color blindness) | Loss of functional M-opsin due to deletions or missense mutations | ClinVar, OMIM |
| Deuteranomaly (anomalous trichromacy) | Altered spectral sensitivity from hybrid gene rearrangements or point mutations | ClinVar, OMIM |
| Blue cone monochromacy (BCM) | Inactivating mutations in both OPN1LW and OPN1MW, leaving only S-cones functional | OMIM #303700 |
| X-linked cone dystrophy | Missense mutations causing progressive cone degeneration | ClinVar, OMIM |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Retina | — | High (cone-specific) |
| Testis | — | Low (non-retinal expression reported) |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| Retinal cone photoreceptors | — | Primary expression site |
| Y79 retinoblastoma cell line | — | Low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.607C>T (p.Arg203Trp) | Missense | Rare | Reduced spectral sensitivity; associated with deuteranomaly |
| c.886A>G (p.Asn296Asp) | Missense | Rare | Alters peak wavelength; linked to color vision variation |
| Exon 2–5 deletion | Structural | — | Causes deuteranopia (complete loss of M-opsin) |
| c.532G>A (p.Gly178Arg) | Missense | Rare | Associated with X-linked cone dystrophy |
Mutation functional classification
Loss of Function (LOF)
Deletions or nonsense mutations that abolish M-opsin expression or function, leading to deuteranopia or blue cone monochromacy.
Gain of Function (GOF)
Not described for OPN1MW.
Dominant Negative (DN)
Not described; OPN1MW mutations are typically recessive or X-linked.
View complete mutation data：
Gene Ontology (GO)
| • G-protein coupled receptor activity (GO:0004930) | • Photoreceptor activity (GO:0009882) |
| • Visual perception (GO:0007601) | • Response to light stimulus (GO:0009416) |
| • Integral component of membrane (GO:0016021) |
Pathways
• Phototransduction cascade (Reactome R-HSA-2188538)
• Visual signal transduction (KEGG hsa04744)
Protein Summary
The M-opsin protein (364 amino acids) is a seven-transmembrane G-protein-coupled receptor that binds 11-cis-retinal as a chromophore. Upon photon absorption, it activates transducin and initiates the phototransduction cascade. The protein is localized to the outer segment of cone photoreceptors. Polymorphisms in OPN1MW contribute to normal variation in color vision, while pathogenic mutations cause inherited color blindness and retinal degeneration.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| OPN1MW2 Knockout HEK293 Cell Line | EDJ-KQ14566 | Human | 728458 | Details Get a Quote |
| OPN1MW3 Knockout HEK293 Cell Line | EDJ-KQ14567 | Human | 101060233 | Details Get a Quote |
| OPN1MW Knockout HEK293 Cell Line | EDJ-KQ50296 | Human | 2652 | Details Get a Quote |
| OPN1MW Knockout HeLa Cell Line | EDJ-KQ53320 | Human | 2652 | Details Get a Quote |
| OPN1MW2 Knockout HeLa Cell Line | EDJ-KQ60711 | Human | 728458 | Details Get a Quote |
| OPN1MW Knockout A-549 Cell Line | EDJ-KQ61803 | Human | 2652 | Details Get a Quote |
| OPN1MW2 Knockout A-549 Cell Line | EDJ-KQ69183 | Human | 728458 | Details Get a Quote |
| OPN1MW Knockout HCT 116 Cell Line | EDJ-KQ70289 | Human | 2652 | Details Get a Quote |
| OPN1MW2 Knockout HCT 116 Cell Line | EDJ-KQ77537 | Human | 728458 | Details Get a Quote |
