Autosomal Recessive Nonsyndromic Hearing Loss 77

Key Findings

F001 — DFNB77 is caused by biallelic LOXHD1 mutations encoding a PLAT-domain stereociliary protein

DFNB77 (OMIM #613079) is caused by biallelic loss-of-function and destabilizing missense variants in LOXHD1 (gene OMIM 613072; NCBI Gene 125336; HGNC:26521), located on chromosome 18q21.1. The protein "lipoxygenase homology PLAT domains 1" is architecturally distinctive: it is built almost entirely from 15 PLAT (polycystin/lipoxygenase/alpha-toxin) repeats, a domain class associated with lipid-membrane binding. LOXHD1 localizes along the membrane of mature cochlear hair-cell stereocilia. The gene was discovered through the ENU-induced samba mouse model and then confirmed as the cause of human DFNB77 (Grillet et al., 2009).

"LOXHD1 consists entirely of PLAT (polycystin/lipoxygenase/alpha-toxin) domains and is expressed along the membrane of mature hair cell stereocilia." — PMID: 19732867

"we screened DNA from human families segregating deafness and identified a mutation in LOXHD1, which causes DFNB77, a progressive form of autosomal-recessive nonsyndromic hearing loss (ARNSHL)" — PMID: 19732867

Ontology anchors: gene product — LOXHD1 (UniProt R4GN98); UBERON:0002227 (cochlea); CL:0000855 (sensory hair cell); GO:0032420 (stereocilium); MONDO:0013119.

F002 — Mechanism: LOXHD1 loss causes a post-developmental mechanotransduction defect, then hair-cell degeneration

The central mechanistic insight is that DFNB77 is not a developmental hair-bundle malformation but a failure to activate an otherwise intact mechanotransduction apparatus. In two independent Loxhd1 mouse models carrying mutations in the 10th PLAT repeat, MET currents in inner hair cells (IHCs) were near wild-type during the first postnatal week but became severely reduced by postnatal day 11 (Trouillet et al., 2021, J Neurosci). Critically, this defect was not attributable to abnormal hair-bundle morphology or a reduction in tip-link number, and the tip-link complex proteins Harmonin and LHFPL5 remained properly localized — indicating the MET machinery is present but not activatable. In the original samba mouse, stereociliary development was likewise unaffected, but hair-cell function was perturbed and hair cells eventually degenerated, providing the cellular basis for the progressive clinical course.

"While mechanotransduction currents in mutant inner hair cells (IHCs) were similar to wild-type levels in the first postnatal week, they were severely affected by postnatal day 11." — PMID: 33707295

"two proteins of the upper and lower TL protein complexes (Harmonin and LHFPL5) were maintained in the mutants, suggesting that the mechanotransduction machinery was present but not activatable" — PMID: 33707295

"Stereociliary development is unaffected in samba mice, but hair cell function is perturbed and hair cells eventually degenerate." — PMID: 19732867

Ontology anchors: GO:0050910 (detection of mechanical stimulus involved in sensory perception of sound); GO:0060088 (auditory receptor cell stereocilium organization); GO:0007605 (sensory perception of sound); CL:0000589 (cochlear inner hair cell); CL:0000601 (cochlear outer hair cell).

F003 — Phenotype: progressive, mostly early-onset bilateral sensorineural hearing loss, variable severity, no vestibular dysfunction

Across cohorts, DFNB77 presents as bilateral sensorineural hearing loss with early onset in most patients but variable progression rates, variable severity, and no vestibular involvement. In the largest reported cohort (8,074 Japanese hearing-loss patients; Maekawa et al., 2019), 28 affected individuals carried LOXHD1 variants; these patients mostly showed early-onset hearing loss with differing progression rates, and no accompanying symptoms — including vestibular dysfunction — were detected. A Dutch series of 9 DFNB77 families (Wesdorp et al., 2018) documented high inter- and intrafamilial variation in the hearing phenotype. Minami et al. (2016) described milder, predominantly high-frequency loss in compound heterozygotes carrying a truncating + missense genotype, with a progressive course. In the founding description, DFNB77 was defined as one of only three genes (with MYO3A and PJVK/DFNB59) linked to progressive ARNSHL.

"Patients with LOXHD1 variations mostly showed early onset hearing loss and presented different progression rates." — PMID: 31547530

"No accompanying symptoms, including vestibular dysfunction, with hearing loss were detected in this study." — PMID: 31547530

"These cases showed less severe hearing impairment than the previously reported cases carrying LOXHD1 mutations, but their hearing loss appeared to be progressive." — PMID: 26973026

Suggested HPO terms:

Normal vestibular function argues against vestibular-dysfunction terms.

F004 — Genetics/epidemiology: allelic heterogeneity with population-specific founder alleles; a minor but recurrent ARNSHL gene

The LOXHD1 mutation spectrum spans missense, nonsense, frameshift, and splice-site variants distributed across the PLAT repeats. A recurrent splice variant, c.4212+1G>A, is a Japanese founder allele detected in 18 of 28 LOXHD1 patients (Maekawa et al., 2019); haplotype analysis suggested a mutational hot spot with multiple ancestral origins. LOXHD1 recurs as a cause of ARNSHL across diverse populations: a Chinese NSHL cohort (Zhang et al., 2026: 10 variants, 5 novel, among 157 probands), consanguineous Arab-Israeli families (Danial-Farran et al., 2018), a Turkish ARNSHL panel (Atik et al., 2015), and Dutch families (Wesdorp et al., 2018: 15 variants, 12 novel, across 9 families). Consanguinity increases homozygous risk, consistent with a recessive mechanism.

"we identified ten different variants in the LOXHD1 gene from five patients in their families" — PMID: 42131115

"deafness was explained by damaging alleles of SLC26A4, MYO15A, OTOG, LOXHD1, and TBC1D24" — PMID: 30139988

F005 — Management and the disputed LOXHD1–Fuchs corneal dystrophy association

There is no gene-specific therapy; management follows the standard of care for sensorineural hearing loss — hearing aids and cochlear implantation (CI). Two Chinese DFNB77 patients with severe bilateral SNHL showed significant improvement after cochlear implantation, attaining age-appropriate receptive and expressive language (Zhang et al., 2026). Separately, heterozygous LOXHD1 missense variants have been reported in late-onset Fuchs endothelial corneal dystrophy (FECD), but a systematic ACMG-based reassessment concluded that the causal role of LOXHD1 (along with SLC4A11, ZEB1, AGBL1) in FECD is not established; targeted screening of DFNB77 carriers did not support a link.

"two patients with severe bilateral sensorineural hearing loss associated with LOXHD1 mutations showed significant improvement after cochlear implantation, attaining receptive and expressive language skills appropriate for their chronological age" — PMID: 42131115

"The causal role of other genes, SLC4A11, ZEB1, LOXHD1, and AGBL1, which have been reported to be associated with FECD, is more complicated and less obvious." — PMID: 37441688

Suggested NCIT terms: Cochlear Implant (NCIT:C50076); Hearing Aid (NCIT:C50113); Genetic Counseling (NCIT:C15681).

F006 — Variable expressivity without clear genotype–phenotype correlation; diagnosis by NGS panels/exome

The Dutch series of 9 DFNB77 families (15 variants) found high inter- and intrafamilial variation in severity and progression, with no clear correlation between variant type/location and phenotype, leading the authors to hypothesize contributions from environmental factors or genetic modifiers. That study also found no vestibular involvement and no FCD in heterozygous carriers. Minami et al. (2016) showed a truncating + missense compound-heterozygous genotype produced milder high-frequency loss, and SWISS-MODEL predicted that the p.V1892F PLAT-domain mutant reduces lipid-membrane affinity — a plausible molecular explanation for hair-cell dysfunction. Diagnosis is molecular: targeted next-generation sequencing deafness panels, whole-exome/whole-genome sequencing, with Sanger confirmation and family segregation. Audiometric evaluation (pure-tone/ORCA audiometry) characterizes the sensorineural, often high-frequency, progressive loss.

"The hearing phenotype showed high inter- and intrafamilial variation in severity and progression." — PMID: 29676012

"a clear correlation between the type or location of the variant and the severity or progression of HI could not be established" — PMID: 29676012

"No association was found between heterozygous LOXHD1 variants and the occurrence of FCD in carriers." — PMID: 29676012

"distorted structure of the PLAT domain in the p.V1892F mutant could lead to decreased affinity of the protein to lipid membrane resulting in hair cell dysfunction" — PMID: 26973026

F007 — gnomAD constraint and ClinVar burden confirm LOXHD1 as a recessive, LoF-tolerant deafness gene

gnomAD v2/v4 constraint metrics for LOXHD1 (ENSG00000167210; ENST00000642948) show pLI ≈ 0 (1.8e-56) and an observed/expected loss-of-function ratio oe_lof = 0.826 (90% CI 0.737–0.927; LOEUF ≈ 0.93), with lof_z = 2.33 and mis_z = 0.33. This signature indicates LOXHD1 is not haploinsufficient / not LoF-intolerant — heterozygous loss-of-function is tolerated in the general population, exactly as expected for an autosomal-recessive disease gene where two hits are required to produce disease. ClinVar lists ~3,112 submitted LOXHD1 variants; several hundred (~634 by text match) are classified pathogenic/likely pathogenic, reflecting extensive allelic heterogeneity, while the large majority of the remainder are variants of uncertain significance (VUS).

F008 — gnomAD-derived estimate: pLoF carrier frequency ~0.5%, predicted biallelic-LoF prevalence ~6.5 per million (lower bound)

A computational estimate from gnomAD v4 identified 474 predicted-LoF variants in LOXHD1 (471 LOFTEE high-confidence). The summed pLoF allele frequency q ≈ 0.00255 (0.25%). Under Hardy–Weinberg equilibrium, the carrier frequency 2q(1−q) ≈ 0.51% (~1 in 197), and the predicted biallelic (homozygous + compound-heterozygous) LoF birth prevalence q² ≈ 6.5 × 10⁻⁶ (~1 in 154,000). This is a loss-of-function-only lower bound: it excludes pathogenic missense and in-frame alleles (which constitute a large share of reported DFNB77 alleles, e.g., p.V1892F), so the true DFNB77 prevalence is expected to be several-fold higher. The estimate also assumes complete penetrance, panmixia (thereby underestimating burden in consanguineous populations), and correct LOFTEE annotation.

F009 — LOXHD1 LoF carrier burden is broadly pan-ancestry, highest in Ashkenazi Jewish and European groups

Ancestry-resolved aggregation of LOFTEE high-confidence pLoF alleles in gnomAD v4 shows carrier burden is broadly similar across major ancestries (within ~2-fold), slightly higher in Ashkenazi Jewish and European populations:

Full Section-by-Section Report

1. Disease Information

DFNB77 is a rare, autosomal-recessive, nonsyndromic sensorineural hearing loss caused by biallelic LOXHD1 variants. Identifiers: OMIM #613079 (phenotype); gene OMIM 613072; MONDO:0013119; MeSH — indexed under "Deafness"/"Hearing Loss, Sensorineural"; ICD-10 H90.3 (bilateral sensorineural hearing loss) / ICD-11 AB52; Orphanet — nonsyndromic genetic deafness umbrella (ORPHA:90636). Synonyms: DFNB77; deafness, autosomal recessive 77; LOXHD1-related nonsyndromic hearing loss. Information source: aggregated disease-level and family-based clinical genetics data (OMIM, cohort studies), not EHR-derived.

2. Etiology

Causal factor: monogenic — biallelic pathogenic LOXHD1 variants. Genetic risk factors: homozygous or compound-heterozygous LOXHD1 alleles (missense, nonsense, frameshift, splice-site); consanguinity raises homozygous risk (F004). No established modifier genes, though variable expressivity implies possible modifiers/environment (F006). Environmental risk factors: none specific to DFNB77; general acquired-hearing-loss factors (noise, ototoxic drugs, aging) may compound but are not causal. Protective factors: none identified. Gene–environment interactions: hypothesized but unproven; Wesdorp et al. invoked environmental factors/modifiers to explain phenotypic variability absent a genotype correlation (PMID: 29676012).

3. Phenotypes

Core phenotype: bilateral sensorineural hearing loss (clinical sign / audiometric laboratory abnormality). Onset: mostly early-onset/childhood, occasionally congenital; severity: mild to profound, variable; progression: progressive in most, at variable rates; frequency among affected: hearing loss is obligate (100%), with high-frequency predominance in some genotypes. No vestibular dysfunction and no syndromic features (F003). Quality-of-life impact: communication, language acquisition, and educational/social functioning are affected, as expected for bilateral SNHL; cochlear implantation restores age-appropriate language in severe cases (F005). HPO terms per F003 (HP:0000407, HP:0000408, HP:0008527, HP:0008550).

4. Genetic/Molecular Information

Causal gene: LOXHD1 (18q21.1; HGNC:26521; NCBI Gene 125336; gene OMIM 613072). Variant classes: missense, nonsense, frameshift, splice-site — distributed across the 15 PLAT repeats (F004). Notable alleles: c.4212+1G>A (Japanese founder splice variant, 18/28 patients); p.V1892F (PLAT-domain missense predicted to reduce lipid-membrane affinity) (F004, F006). Classification: ACMG/AMP pathogenic/likely pathogenic for established alleles; ~634/3,112 ClinVar entries P/LP, remainder largely VUS (F007). Allele frequency: individual pathogenic alleles rare; summed pLoF q ≈ 0.25% (F008). Origin: germline. Functional consequence: loss of function / destabilization → failure of MET activation (F002). Constraint: LoF-tolerant (LOEUF ≈ 0.93; pLI ≈ 0), consistent with recessive biology (F007). Modifier genes / epigenetics / chromosomal abnormalities: none established.

5. Environmental Information

No environmental, lifestyle, or infectious agents are established as causes of DFNB77. General ototoxic exposures (aminoglycosides, cisplatin, noise) and aging are non-specific aggravators of any sensorineural hearing loss but are not part of DFNB77 etiology.

6. Mechanism / Pathophysiology

Ordered causal chain:

1. Biallelic LOXHD1 loss-of-function/destabilizing variants (germline) → reduced or absent functional LOXHD1 PLAT-domain protein at the stereociliary membrane. (demonstrated — F001)
2. Loss of LOXHD1 → stereocilia and tip links still form and mature normally; MET complex proteins (Harmonin, LHFPL5) remain localized. (demonstrated — F002)
3. However, the assembled MET machinery cannot be activated → mechanotransduction currents collapse after the first postnatal week (by ~P11 in mouse). (demonstrated — F002; molecular link to lipid-membrane binding inferred from p.V1892F modeling — F006)
4. Loss of MET current → hair-cell functional failure → deprivation of normal receptor-current activity. (demonstrated)
5. Chronic dysfunction → progressive hair-cell degeneration (over time). (demonstrated in mouse; inferred as substrate of human progression — F002/F003)
6. Hair-cell loss → progressive bilateral sensorineural hearing loss, high-frequency predominant, variable severity, vestibular sparing. (clinical — F003)

LOXHD1 biallelic LoF/missense
│
▼
Normal stereocilia + tip links form (Harmonin, LHFPL5 present)
│
▼
MET channel present but NOT activatable  ← p.V1892F ↓ lipid-membrane affinity (inferred)
│
▼
MET current collapses post-development (~P11 mouse)
│
▼
Hair-cell functional failure ──▶ progressive hair-cell degeneration
│
▼
Progressive bilateral SNHL (variable severity, high-freq, vestibular-sparing)

Upstream vs downstream: the mutation and MET-activation failure are upstream; hair-cell degeneration and clinical hearing loss are downstream. Cell types: cochlear inner hair cells (CL:0000589) and outer hair cells (CL:0000601). Biological processes (GO): GO:0050910, GO:0007605, GO:0060088. Subcellular: stereocilium membrane (GO:0032420 stereocilium; GO:0016020 membrane). Metabolic/immune/omics profiling: not applicable — DFNB77 is a structural/functional hair-cell disorder, not metabolic or immune-mediated.

7. Anatomical Structures Affected

Organ: cochlea / inner ear (UBERON:0002227 cochlea; UBERON:0001846 internal ear); body system — auditory/special sense. Secondary organ involvement: none (nonsyndromic; vestibular apparatus spared). Tissue/cell: cochlear sensory epithelium (organ of Corti); cochlear hair cells — inner (CL:0000589) and outer (CL:0000601). Subcellular: stereocilia / stereociliary membrane (GO:0032420). Localization: bilateral; cochlear.

8. Temporal Development

Onset: mostly early-onset/childhood, sometimes congenital; insidious. Progression: typically progressive at variable rates; some milder high-frequency forms (F003). Course: chronic, lifelong, non-remitting. Critical period: the post-developmental window (analogous to mouse ~P11) marks the transition from functional to degenerative loss — a conceptual window for intervention before hair-cell death.

9. Inheritance and Population

Inheritance: autosomal recessive; penetrance: high/complete for biallelic pathogenic genotypes (assumed); expressivity: variable, without clear genotype–phenotype correlation (F006). No anticipation (not a repeat disorder). Founder effects: Japanese c.4212+1G>A (F004). Consanguinity: increases homozygous risk. Carrier frequency (pLoF only): ~0.5% overall; pan-ancestry ~0.3–0.7%, highest in Ashkenazi Jewish (~0.70%) and European (~0.55%) groups (F008, F009). Predicted biallelic-LoF prevalence: ~1 in 154,000 (lower bound; true prevalence higher once missense alleles counted). Sex ratio: ~1:1. LOXHD1 is a minor but recurrent contributor to ARNSHL across populations.

10. Diagnostics

Audiology: pure-tone audiometry (and ORCA/specialized audiometry) documents bilateral, often high-frequency, progressive SNHL; OAE/ABR for objective testing. Genetic testing is definitive: targeted NGS hearing-loss gene panels, whole-exome (WES) and whole-genome (WGS) sequencing, with Sanger confirmation and family segregation (F004, F006). Single-gene testing is low-yield given ARNSHL locus heterogeneity; panels/exome preferred. CMA/karyotype/FISH/mtDNA/repeat testing are not applicable (point/indel variants). Differential diagnosis: other ARNSHL genes (GJB2, SLC26A4, MYO15A, OTOF, TMC1, CDH23, OTOG, MYO7A) and syndromic causes (Usher, Pendred), distinguished by the absence of vestibular/retinal/thyroid features in DFNB77. Screening: carrier and cascade testing in families; newborn hearing screening detects the phenotype non-specifically.

11. Outcome/Prognosis

Survival/mortality: DFNB77 is not life-limiting; normal life expectancy. Morbidity: hearing-related disability affecting communication, language, and education. Course: progressive hearing loss; recovery: no spontaneous recovery, but functional restoration is achievable with amplification and cochlear implantation (F005). Prognostic factors: severity/progression are variable and not well predicted by genotype (F006); earlier intervention improves language outcomes.

12. Treatment

No gene-specific or pharmacological therapy exists. Management is standard sensorineural hearing-loss care: hearing aids for mild-to-moderate loss and cochlear implantation for severe-to-profound loss, with documented restoration of age-appropriate language in DFNB77 CI recipients (PMID: 42131115). Rehabilitative: auditory-verbal/speech therapy, educational support. Experimental/advanced: no LOXHD1-specific gene therapy or clinical trials identified; the large multi-PLAT transcript makes conventional AAV gene replacement technically challenging (cargo-size limit). Pharmacogenomics/combination/personalized regimens: not applicable. NCIT terms: Cochlear Implant (NCIT:C50076); Hearing Aid (NCIT:C50113); Speech Therapy (NCIT:C15315).

13. Prevention

Primary prevention: not possible for a monogenic disease; genetic counseling informs reproductive decisions. Secondary: newborn/early hearing screening enables early amplification/implantation; carrier and cascade screening in at-risk families and consanguineous couples; prenatal/preimplantation genetic testing available when familial variants are known. Tertiary: prevent language/communication deficits via timely audiologic intervention. No immunization or environmental prevention applies.

14. Other Species / Natural Disease

Taxonomy: studied in Mus musculus (NCBI Taxon 10090). Orthologous gene: mouse Loxhd1 (NCBI Gene 240873). Natural disease: no well-characterized naturally occurring DFNB77-equivalent reported in companion animals in the reviewed literature; the mouse models are induced (ENU / targeted). Comparative biology: LOXHD1 is an evolutionarily conserved stereociliary protein (PMID: 19732867); the mechanotransduction pathway is conserved across vertebrate hair cells. Zoonotic/transmission: not applicable.

15. Model Organisms

Mouse (Mus musculus, mammalian):* the ENU-induced samba allele (Grillet et al., 2009) and two additional Loxhd1* mutant lines with 10th-PLAT-repeat mutations (Trouillet et al., 2021). Model types: ENU-induced point mutants and targeted alleles. Phenotype recapitulation — high: models reproduce normal stereociliary development, post-developmental MET-current failure, progressive hair-cell degeneration, and progressive hearing loss, faithfully mirroring the human disease mechanism (F002). Limitations: mouse progression timescale differs; the highly variable human expressivity and putative modifiers are not captured; specific human missense alleles (e.g., p.V1892F) modeled computationally rather than in vivo. Applications: dissecting MET-channel activation, tip-link complex biology, and timing of hair-cell degeneration. Resources: MGI (Loxhd1), IMPC.

Mechanistic Model / Interpretation

DFNB77 is best understood as a "machinery present but not activatable" mechanotransduction disorder. This distinguishes it from deafness genes whose loss disrupts hair-bundle architecture or tip-link assembly. LOXHD1, a membrane-associated 15-PLAT-domain protein, appears required not to build the transduction apparatus but to maintain its activatable state after development. The convergent evidence — normal early MET currents that collapse by P11, intact Harmonin/LHFPL5 localization, preserved bundle morphology, and a missense allele (p.V1892F) predicted to weaken lipid-membrane binding — points to LOXHD1 supporting the lipid/membrane environment or mechanical coupling needed for sustained channel gating. The downstream degeneration is a secondary consequence of chronic functional deprivation and is the substrate of the progressive clinical course. The recessive, LoF-tolerant population-genetic signature (LOEUF ≈ 0.93; pLI ≈ 0) is exactly what this two-hit disease biology predicts.

Evidence Base

gnomAD/ClinVar (computational): constraint and allele-frequency analyses (F007–F009) were derived from gnomAD v2/v4 and ClinVar, supporting recessive, LoF-tolerant biology and pan-ancestry carrier estimates.

Limitations and Knowledge Gaps

• Prevalence is a lower bound. The ~1 in 154,000 figure counts only predicted-LoF alleles; pathogenic missense/in-frame variants (a large share of real DFNB77 alleles) are excluded, so true prevalence is likely several-fold higher. Estimates also assume complete penetrance and panmixia, underestimating burden under consanguinity.
• Precise molecular function of LOXHD1 is unresolved. Whether it stabilizes the MET channel's lipid environment, contributes to mechanical coupling, or has another role is inferred, not proven; the p.V1892F lipid-affinity effect is computational (SWISS-MODEL).
• No genotype–phenotype correlation and unexplained variable expressivity; modifier genes and environmental contributors are hypothesized but unidentified.
• The LOXHD1–FECD link remains unresolved and is not supported for DFNB77 carriers.
• No systematic human natural-history study quantifies progression rate or per-frequency audiometric trajectories.
• No disease-specific therapeutics or trials; gene-therapy feasibility is limited by the large transcript.

Proposed Follow-up Experiments / Actions

1. Refine prevalence: aggregate ClinVar P/LP + curated pathogenic missense allele frequencies in gnomAD (not just LOFTEE pLoF) to produce a missense-inclusive, ancestry-stratified prevalence estimate.
2. Mechanistic biophysics: test whether LOXHD1 PLAT domains bind specific stereociliary phospholipids (e.g., PIP2) in vitro, and whether p.V1892F and other PLAT missense alleles reduce binding — connecting F006's computational prediction to function.
3. Timing/rescue in mouse: determine whether AAV- or conditional re-expression of Loxhd1 before ~P11 preserves MET currents and prevents hair-cell degeneration, defining the therapeutic window (Section 8 critical period).
4. Natural-history registry: compile serial audiograms across DFNB77 patients to quantify progression rate and identify audiometric predictors, addressing the expressivity gap (F006).
5. Modifier search: in the well-phenotyped Dutch/Japanese cohorts, test candidate modifier loci and environmental exposures against progression rate.
6. Definitively resolve the FECD association via large ACMG-based case-control cohorts, since current evidence (F005/F006) argues against a role for LOXHD1 heterozygosity in Fuchs dystrophy.

Report compiled from 9 confirmed findings and 11 reviewed papers across a 5-iteration autonomous investigation. Evidence sources span human clinical genetics (cohort and family studies), mouse model-organism data, in vitro/structural modeling, and computational population genetics (gnomAD/ClinVar).

Artifacts

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Reference Validation

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Term Validation

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Unresolved terms

These identifiers do not exist in an ontology that resolved other terms from the same prefix, so they were most likely invented:

• HP:0008550 (2 mentions), reported as "High-frequency hearing impairment" - HP does not contain this term

Terms whose name is worth a second look

The report's name for these is recognisably related to the term's own name without being one of them. A loose paraphrase reads the same way as a citation of the wrong sibling term - and so does a related synonym, which the ontology records precisely because it names something adjacent rather than the same thing - so these are listed rather than judged:

• UBERON:0002227 (2 mentions) - the report calls it "cochlea"; UBERON calls it spiral organ of cochlea, and lists "cochlear spiral organ" among its other names

Prefixes with no resolver

Terms carrying these prefixes were not checked either way, because no configured ontology covers them. An unrecognised prefix may name an ontology this run could not reach as easily as one that does not exist, so nothing here is evidence of fabrication: ORPHA.