CLRN2: Clarin 2
Gene associated with Usher syndrome and hearing loss
Gene Information Card
| Symbol | CLRN2 |
|---|---|
| Full Name | clarin 2 |
| Gene Type | protein-coding |
| Chromosomal Location | 4p15.32 |
| NCBI Gene ID | 653574 ncbi.nlm.nih.gov/gene/653574 |
| Ensembl ID | ENSG00000198093 |
| UniProt ID | Q5T9L3 |
| OMIM ID | 614257 |
| HGNC ID | 33894 |
| Aliases | USH3B, DFNB117 |
Description
CLRN2 (clarin 2) is a protein-coding gene located on chromosome 4p15.32. It encodes a transmembrane protein belonging to the clarin family, which is involved in hair cell function in the inner ear and photoreceptor cell function in the retina. Mutations in CLRN2 are associated with autosomal recessive Usher syndrome type 3B (USH3B) and nonsyndromic hearing loss (DFNB117). The protein is essential for the structural integrity and function of stereocilia in cochlear hair cells and photoreceptor synapses.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Usher syndrome type 3B (USH3B) | Loss of function of clarin 2 disrupts hair cell and photoreceptor function, leading to progressive hearing loss and retinitis pigmentosa. | OMIM #614257; ClinVar |
| Nonsyndromic hearing loss (DFNB117) | Biallelic mutations in CLRN2 cause autosomal recessive nonsyndromic hearing loss without retinal involvement. | OMIM #618184; ClinVar |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Cochlea | Not available | High (based on RNA-seq) |
| Retina | Not available | Moderate |
| Testis | Not available | Low |
| Brain | Not available | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | Not available | Used for heterologous expression studies |
| HeLa | Not available | Low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.475C>T (p.Arg159*) | Nonsense | Rare | Loss of function; associated with USH3B |
| c.2T>C (p.Met1?) | Start loss | Rare | Loss of function; associated with DFNB117 |
| c.254T>C (p.Leu85Pro) | Missense | Rare | Likely loss of function; reported in hearing loss |
Mutation functional classification
Loss of Function (LOF)
Most CLRN2 mutations are loss-of-function (nonsense, frameshift, start loss) leading to truncated or absent protein, causing Usher syndrome or nonsyndromic hearing loss.
Gain of Function (GOF)
No gain-of-function mutations reported.
Dominant Negative (DN)
No dominant-negative mutations reported.
View complete mutation data：
Gene Ontology (GO)
| • plasma membrane (GO:0005886) | • integral component of membrane (GO:0016021) |
| • sensory perception of sound (GO:0007605) | • visual perception (GO:0007601) |
| • protein binding (GO:0005515) |
Pathways
• Usher syndrome (KEGG: hsa05016)
• Phototransduction (Reactome: R-HSA-2188538)
Protein Summary
Clarin 2 is a transmembrane protein of 232 amino acids, containing a conserved Pfam domain (PF07679) characteristic of the clarin family. It localizes to the plasma membrane of hair cell stereocilia and photoreceptor synapses, where it mediates cell adhesion and synaptic function. The protein is essential for maintaining the structural integrity of hair bundles in the inner ear and for normal retinal function.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| CLRN2 Knockout HEK293 Cell Line | EDJ-KQ12951 | Human | 645104 | Details Get a Quote |
| CLRN2 Knockout HeLa Cell Line | EDJ-KQ60580 | Human | 645104 | Details Get a Quote |
| CLRN2 Knockout A-549 Cell Line | EDJ-KQ69050 | Human | 645104 | Details Get a Quote |
| CLRN2 Knockout HCT 116 Cell Line | EDJ-KQ77405 | Human | 645104 | Details Get a Quote |
