USH1G
Usher Syndrome Type 1G Gene (SANS)
Gene Information Card
| Symbol | USH1G |
|---|---|
| Full Name | Usher Syndrome 1G (SANS) |
| Gene Type | Protein coding |
| Chromosomal Location | 17q25.1 |
| NCBI Gene ID | 124590 ncbi.nlm.nih.gov/gene/124590 |
| Ensembl ID | ENSG00000182093 |
| UniProt ID | Q495M9 |
| OMIM ID | 607696 |
| HGNC ID | 16356 |
| Aliases | SANS, ANKS4A |
Description
The USH1G gene encodes the scaffold protein SANS, which is essential for the development and maintenance of hair cell stereocilia in the inner ear and photoreceptor cell function in the retina. SANS interacts with other Usher syndrome proteins (e.g., USH2A, harmonin) to form a multiprotein complex involved in mechanotransduction and ciliary transport. Loss-of-function mutations in USH1G cause Usher syndrome type 1G, characterized by congenital profound sensorineural hearing loss, vestibular dysfunction, and prepubertal onset retinitis pigmentosa.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Usher syndrome type 1G | Loss-of-function mutations in USH1G disrupt the stereociliary ankle-link complex and photoreceptor ciliary transport, leading to hair cell degeneration and retinal dystrophy. | ClinVar, OMIM #607696 |
| Retinitis pigmentosa (non-syndromic) | Rare missense variants may impair SANS function in photoreceptor cilia without affecting hearing. | ClinVar, literature |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Cochlea | — | High (RNA, protein) |
| Retina | — | High (RNA, protein) |
| Testis | — | Moderate (RNA) |
| Brain | — | Low (RNA) |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | — | Used for recombinant expression studies |
| ARPE-19 (retinal pigment epithelium) | — | Endogenous expression detected |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.496C>T (p.Arg166*) | Nonsense | Rare | Premature stop; loss of SANS protein; causes Usher syndrome type 1G |
| c.648delG (p.Gly217Alafs*12) | Frameshift | Rare | Frameshift leading to truncated protein; pathogenic |
| c.73C>T (p.Arg25*) | Nonsense | Rare | Nonsense-mediated decay; loss of function |
Mutation functional classification
Loss of Function (LOF)
Majority of USH1G mutations are loss-of-function (nonsense, frameshift, splice-site) leading to truncated or absent SANS protein, causing Usher syndrome type 1G.
Gain of Function (GOF)
No gain-of-function mutations reported.
Dominant Negative (DN)
No dominant-negative mutations reported; USH1G-associated disease is autosomal recessive.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Usher syndrome interactome (SANS
• harmonin
• USH2A
• whirlin)
• Stereociliary ankle-link complex
• Photoreceptor ciliary transport
Protein Summary
SANS (scaffold protein containing ankyrin repeats and SAM domain) is a 461-amino-acid protein that localizes to the ankle-link region of hair cell stereocilia and the connecting cilium of photoreceptors. It mediates protein-protein interactions within the Usher protein network, anchoring membrane proteins and facilitating intracellular transport. Loss of SANS disrupts hair bundle cohesion and photoreceptor outer segment renewal, leading to combined hearing and vision loss.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| USH1G Knockout HEK293 Cell Line | EDJ-KQ8593 | Human | 124590 | Details Get a Quote |
| USH1G Knockout HCT 116 Cell Line | EDJ-KQ34739 | Human | 124590 | Details Get a Quote |
| USH1G Knockout HeLa Cell Line | EDJ-KQ58134 | Human | 124590 | Details Get a Quote |
| USH1G Knockout A-549 Cell Line | EDJ-KQ66621 | Human | 124590 | Details Get a Quote |
