| domain | established finding | evidence type | suggested ontology terms/IDs | key evidence |
|---|---|---|---|---|
| disease identifier | Autosomal Dominant Nonsyndromic Hearing Loss 25 (DFNA25) is a Mendelian deafness entity linked to SLC17A8 | Human pedigree/genetic discovery | MONDO:0011568; OMIM 605583 | DFNA25 described as an "autosomal-dominant form of progressive, high-frequency nonsyndromic deafness" caused by SLC17A8 mutation (pqac-00000008) |
| causal gene/protein | SLC17A8 encodes vesicular glutamate transporter 3 (VGLUT3) | Human, mouse, review | SLC17A8; VGLUT3; OMIM 607557 | VGLUT3 loads glutamate into inner hair cell synaptic vesicles before release to auditory nerve terminals (pqac-00000008, pqac-00000012) |
| synonyms | DFNA25; deafness, autosomal dominant 25; SLC17A8-related autosomal dominant nonsyndromic hearing loss | Aggregated disease/gene nomenclature with primary literature support | OMIM 605583; SLC17A8-related hearing loss | Primary papers and reviews use DFNA25 / deafness, autosomal dominant 25 terminology (pqac-00000008, pqac-00000012) |
| pathogenic variants | Reported disease-associated variants include c.632C>T (p.A211V), p.M206Nfs*4, and c.763+1G>T | Human genetic studies | HGVS nomenclature where known; ACMG classification not uniformly published | p.A211V segregated in two unrelated families and was absent in 267 controls; p.M206Nfs*4 absent in 100 controls; c.763+1G>T co-segregated in a 3-generation Korean family (pqac-00000008, pqac-00000012, pqac-00000005) |
| inheritance | Inheritance is autosomal dominant | Human pedigree | HP:0000006 Autosomal dominant inheritance | Multiple families showed autosomal-dominant segregation (pqac-00000008, pqac-00000005) |
| core phenotype | Progressive high-frequency sensorineural hearing loss, nonsyndromic | Human clinical | HP:0000407 Sensorineural hearing impairment; HP:0002066 Hearing impairment; high-frequency qualifier if used in HPO mapping | Human families had delayed/progressive high-frequency SNHL without syndromic features (pqac-00000008, pqac-00000012) |
| onset/natural history | Typically delayed/late onset with age-related penetrance increase and progression over time | Human pedigree/clinical | HPO terms for progressive hearing impairment; adult/late onset descriptors as appropriate | DFNA phenotypes are described as delayed-onset and progressive; DFNA25 specifically showed age-related penetrance increase (pqac-00000008, pqac-00000003, pqac-00000012) |
| syndromic status | No consistent extra-auditory syndromic findings established | Human clinical | HP:0000007 Autosomal dominant inheritance; nonsyndromic descriptor | Korean family report noted hearing loss was non-syndromic with no accompanying symptoms (pqac-00000005) |
| primary anatomy | Primary site is the cochlea, especially the organ of Corti inner hair cell synapse | Human-mechanistic inference supported by mouse and expression data | UBERON: cochlea; organ of Corti; inner hair cell | VGLUT3 is selectively expressed in cochlear inner hair cells and mediates afferent transmission (pqac-00000012, pqac-00000008) |
| affected cells | Inner hair cells are primary; type I spiral ganglion neuron afferents are secondarily affected | Mouse physiology/morphology with human disease relevance | CL: inner hair cell; spiral ganglion neuron | Slc17a8-null mice lacked acoustic auditory-nerve responses and later showed decline in afferent synapses and spiral ganglion neurons (pqac-00000008, pqac-00000003) |
| subcellular localization | VGLUT3 localizes to synaptic vesicle-like glutamatergic organelles/ribbon-synapse trafficking compartments in IHCs | Proteomics, prior functional work | GO cellular component: synaptic vesicle; presynaptic active zone; synaptic ribbon | 2024 proteomics isolated "VGluT3-containing membrane vesicles" from IHCs and profiled ribbon-synapse trafficking machinery (pqac-00000011) |
| mechanism | Impaired vesicular glutamate loading/release at the IHC ribbon synapse leads to failure of auditory nerve activation; downstream synapse and neuron loss can follow | Human genetic inference plus mouse functional demonstration | GO: glutamate transport; chemical synaptic transmission; synaptic vesicle cycle | Null mice had absent acoustically evoked ABRs but preserved electrically evoked ABRs and otoacoustic emissions, supporting a synaptic glutamate-release defect rather than OHC failure (pqac-00000008, pqac-00000003) |
| variant-specific mechanism | The human p.A211V allele is modeled by mouse p.A224V and is associated with IHC stereocilia collapse, reduced summating potential, and oversized synaptic ribbons | Mouse knock-in model of human allele | GO: mechanotransduction; synaptic transmission; hair bundle organization | Knock-in mice showed progressive hearing loss with intact cochlear amplification, IHC bundle collapse, and altered ribbon exocytosis, suggesting mechanotransduction failure followed by altered synaptic transfer (pqac-00000006) |
| diagnostic testing | Diagnosis relies on audiologic evaluation plus molecular testing (single gene, deafness panel, WES/WGS depending context) | Clinical genetics practice supported by gene-specific reports | SLC17A8 sequencing; hereditary hearing loss panel | SLC17A8 mutations were identified by candidate-gene sequencing and by whole-exome sequencing in affected families (pqac-00000012, pqac-00000005) |
| electrophysiology | ABR is abnormal from failed acoustic neural transmission; OAE/DPOAE may remain preserved when OHC function is intact | Mouse functional evidence; clinically relevant inference | ABR; otoacoustic emissions | Slc17a8-null mice lacked auditory-nerve responses to sound yet retained robust otoacoustic emissions; p.A224V model had progressive ABR loss with intact DPOAEs (pqac-00000008, pqac-00000006) |
| treatment status | No DFNA25-specific approved molecular therapy identified; current real-world care is supportive/rehabilitative (hearing aids, cochlear implantation as indicated) | Review plus mechanistic/animal evidence | NCIT: Hearing Aid; Cochlear Implantation | Reviews note hearing aids and cochlear implants remain standard care for hereditary deafness; SLC17A8-specific therapy remains preclinical (pqac-00000014, pqac-00000009) |
| cochlear implant implication | Because neural responses to electrical stimulation are preserved in Slc17a8-null mice, cochlear implantation is considered biologically plausible | Mouse translational inference | NCIT: Cochlear Implantation | Electrically evoked ABRs were preserved in null mice, suggesting bypass of the defective IHC synapse may help (pqac-00000003) |
| gene therapy/preclinical | AAV1-VGLUT3 cochlear delivery rescued hearing in Vglut3 knockout mice; early postnatal RWM delivery achieved 100% normal ABR threshold recovery in one series | Mouse preclinical interventional | AAV gene replacement; VGLUT3 gene augmentation | Akil 2012 reported normalized ABR thresholds within 2 weeks; P1-P3 RWM delivery rescued 19/19 mice and some maintained hearing long term (pqac-00000015, pqac-00000016) |
| mature-cochlea translational development | 2023 mature-mouse CSF/cisterna magna delivery of AAV-PHP.B-CBA-VGLUT3-WPRE reportedly restored hearing in SLC17A8-/- mice except at 40 kHz | Review summarizing preclinical primary study | AAV-PHP.B; cisterna magna delivery | 2024 review summarizes mature-mouse rescue at dose 2.27 × 10^11 vg with limited off-target expression reported (pqac-00000013) |
| human trials status | No human interventional trial specific to SLC17A8/DFNA25 was identified in the tool-based search | Trial search / evidence gap | ClinicalTrials.gov status: none identified for this gene-disease pair | Recent reviews discuss human OTOF trials, not SLC17A8-specific trials; trial search returned no relevant SLC17A8 intervention (pqac-00000009, pqac-00000014) |
| model organisms | Key models are Slc17a8 knockout mice and VGLUT3A224V/A224V knock-in mice modeling human p.A211V | Mouse in vivo models | MGI/IMSR resources if needed; Slc17a8 mouse models | Knockout demonstrates synaptic glutamate-release failure; knock-in models progressive/mechanosensory and synaptic pathology (pqac-00000008, pqac-00000006) |
| comparative conservation | The affected alanine residue is conserved across species and among human VGLUT paralogs | Human/mouse comparative sequence evidence | conserved residue annotation | Conservation of A211 supported pathogenic relevance of p.A211V (pqac-00000008) |
| epidemiology | Disease-specific prevalence, incidence, sex ratio, and carrier frequency are not established in the retrieved DFNA25-specific literature | Explicit data gap | not available | Available papers are family-based discovery/screening studies rather than population epidemiology (pqac-00000008, pqac-00000012) |
| penetrance/expressivity | Penetrance appears age-dependent and expressivity likely variable, but robust quantitative estimates are lacking | Human pedigree with data gap | age-dependent penetrance descriptor | Human paper notes age-related penetrance increase; no precise percent penetrance estimate retrieved (pqac-00000003) |
| environmental modifiers | No DFNA25-specific environmental risk or protective modifiers were established in retrieved primary disease papers | Explicit data gap | not available | Reviews discuss generic contributors to hearing loss (noise, aging), but not validated DFNA25-specific gene-environment interactions (pqac-00000008, pqac-00000010) |
| QoL/prognosis gap | No DFNA25-specific quality-of-life or life-expectancy studies were identified; morbidity is expected to derive mainly from chronic progressive hearing impairment | Explicit data gap with general clinical inference | hearing-disability QoL instruments if studied in future | Family reports focus on hearing phenotype/genetics, not QoL or survival outcomes (pqac-00000008, pqac-00000012) |


*Table: This table condenses the most actionable, ontology-ready facts for DFNA25/SLC17A8-related hearing loss, including core identifiers, phenotype, mechanism, models, and treatment status. It also flags major evidence gaps where disease-specific epidemiology, modifiers, and outcomes are not yet established.*