🏷

Classifications

Harrison's Chapter

◆

Subtypes

3

MYOC-related Juvenile Open-Angle Glaucoma

Autosomal dominant JOAG caused by mutations in myocilin (MYOC, the GLC1A locus), the most commonly identified genetic cause. Mutations cluster in the olfactomedin domain, are highly penetrant, and are associated with severe, surgery-prone glaucoma. Mutant myocilin misfolds and aggregates intracellularly in trabecular meshwork cells rather than being secreted, triggering ER stress and TM cell death with consequent IOP elevation.

CYP1B1-related Juvenile Open-Angle Glaucoma

JOAG associated with variants in cytochrome P450 1B1 (CYP1B1, the GLC3A locus classically implicated in primary congenital glaucoma). CYP1B1 variants are typically recessive and contribute to anterior-segment / trabecular meshwork developmental dysgenesis; in some populations (e.g., North Indian cohorts) CYP1B1 is the predominant gene implicated in JOAG, exceeding MYOC.

Sporadic / Non-familial Juvenile Open-Angle Glaucoma

JOAG occurring without an identifiable family history. A substantial fraction of sporadic cases have no MYOC mutation, and de novo MYOC variants have been documented, so screening is warranted irrespective of family history. Proportions of familial versus sporadic disease vary by population.

⚙

Pathophysiology

4

Trabecular Meshwork Immaturity and Outflow Obstruction

The core lesion in JOAG is immaturity/dysgenesis of the conventional (trabecular) aqueous outflow pathway. Unlike acquired age-related trabecular dysfunction in adult POAG, the juvenile outflow apparatus is developmentally underdeveloped, producing high outflow resistance and markedly elevated intraocular pressure despite a grossly open and normal drainage angle.

Trabecular Meshwork Cell CL:0002367

Trabecular Meshwork Development GO:0002930 ⚠ ABNORMAL

Eye Trabecular Meshwork UBERON:0005969 Iridocorneal Angle UBERON:0006206

Downstream

Pressure-Induced Glaucomatous Optic Neuropathy

Show evidence (2 references)

PMID:34536459 SUPPORT Human Clinical

"The pathophysiology underlying the disease is immaturity of the conventional outflow pathways, which may or may not be observed on gonioscopy and anterior segment optical coherence tomography."

Identifies immaturity of the conventional (trabecular) outflow pathway as the central pathophysiology of JOAG, distinguishing it from acquired adult trabecular dysfunction.

PMID:39998747 SUPPORT Human Clinical

"Juvenile onset open-angle glaucoma (JOAG) manifests in individuals under the age of 40, resulting in elevated intraocular pressure and significant optic nerve damage."

Confirms that JOAG (onset under 40 years) is characterized by elevated IOP driven by outflow dysfunction with consequent optic nerve damage.

Mutant Myocilin Misfolding and Trabecular Cell Stress

In MYOC-related JOAG, mutations (predominantly in the olfactomedin domain) cause a gain of toxic function: mutant myocilin aggregates intracellularly in trabecular meshwork cells instead of being secreted. The resulting ER stress and unfolded-protein response causes an early, accelerated timeline of TM cell death, elevated IOP, and downstream glaucomatous optic neuropathy. The early-onset, severe phenotype of JOAG reflects the high-penetrance, toxic gain-of-function nature of these alleles.

Trabecular Meshwork Cell CL:0002367

Endoplasmic Reticulum Unfolded Protein Response GO:0030968 ↑ INCREASED Protein Folding GO:0006457 ⚠ ABNORMAL Apoptotic Process GO:0006915 ↑ INCREASED

Eye Trabecular Meshwork UBERON:0005969

Downstream

Trabecular Meshwork Immaturity and Outflow Obstruction

Show evidence (2 references)

PMID:37217093 SUPPORT In Vitro

"The prevailing pathogenic mechanism involves a gain of toxic function whereby mutant myocilin aggregates intracellularly instead of being secreted, which causes cell stress and an early timeline for TM cell death, elevated intraocular pressure, and subsequent glaucoma-associated retinal degeneration."

Describes the myocilin gain-of-toxic-function mechanism: intracellular aggregation, TM cell stress and early death, elevated IOP, and glaucomatous degeneration, which underlies the severe early-onset MYOC-JOAG phenotype.

PMID:37217093 SUPPORT In Vitro

"While myocilin is expressed in numerous tissues, mutant myocilin is only associated with disease in the anterior segment of the eye, in the trabecular meshwork."

Establishes that mutant myocilin pathology is restricted to the trabecular meshwork of the anterior segment, the site of outflow obstruction in JOAG.

Anterior-Segment / Trabecular Dysgenesis in CYP1B1-related Disease

In CYP1B1-related JOAG, recessive variants in cytochrome P450 1B1 (GLC3A) impair normal development of the eye's aqueous outflow system, producing trabeculodysgenesis and anterior-chamber angle developmental abnormalities that obstruct aqueous outflow and elevate IOP. CYP1B1 is the classic primary congenital glaucoma gene, and its involvement in JOAG links juvenile-onset disease to a developmental, dysgenetic mechanism rather than purely degenerative outflow failure.

Trabecular Meshwork Development GO:0002930 ⚠ ABNORMAL Eye Development GO:0001654 ⚠ ABNORMAL

Eye Trabecular Meshwork UBERON:0005969 Anterior Chamber of Eyeball UBERON:0001766

Downstream

Trabecular Meshwork Immaturity and Outflow Obstruction

Show evidence (2 references)

PMID:39998747 SUPPORT Human Clinical

"Analysis reveals a higher prevalence of CYP1B1 gene variants (22.5%) relative to MYOC gene variants (4.5%), suggesting that CYP1B1 is the predominant gene implicated in JOAG among Indian patients."

Demonstrates that CYP1B1 variants can be the predominant genetic cause of JOAG in some populations, supporting CYP1B1-related developmental dysgenesis as a distinct JOAG subtype mechanism.

PMID:32421983 PARTIAL Human Clinical

"It is caused by genetic structural defects in the trabecular meshwork and makes its appearence in newborns and children no older than three years."

Establishes CYP1B1 (the GLC3A locus) as causing trabecular meshwork structural/developmental defects; this developmental dysgenesis mechanism extends to CYP1B1-related juvenile-onset disease.

Pressure-Induced Glaucomatous Optic Neuropathy

Sustained, markedly elevated IOP in JOAG causes mechanical and ischemic stress on the optic nerve head, producing retinal ganglion cell loss and characteristic large discs with deep, steep cupping. Because the disease affects young patients, the cumulative lifetime burden of optic nerve damage and projected disability is higher than in adult-onset glaucoma.

Retinal Ganglion Cell CL:0000740

Apoptotic Process GO:0006915 ↑ INCREASED

Optic Disc UBERON:0001783 Retina UBERON:0000966

Show evidence (2 references)

PMID:34536459 SUPPORT Human Clinical

"The unique optic nerve head features include large discs with deep, steep cupping associated with high IOP-induced damage."

Documents the distinctive JOAG optic nerve head phenotype (large discs, deep steep cupping) driven by high IOP-induced damage.

PMID:34536459 SUPPORT Human Clinical

"Progression rates among JOAG patients are comparable to adult primary glaucomas, but as the disease affects younger patients, the projected disability from this disease is higher."

Supports the higher projected lifetime disability of JOAG due to early onset, motivating aggressive management of the optic neuropathy.

⬡

Pathograph

Use the checkboxes to hide or show graph categories. Hover nodes for evidence and cross-linked metadata.

●

Phenotypes

5

Eye 2

Visual Field Loss FREQUENT Visual field defect HP:0001123

Show evidence (1 reference)

PMID:39998747 SUPPORT Human Clinical

"Juvenile onset open-angle glaucoma (JOAG) manifests in individuals under the age of 40, resulting in elevated intraocular pressure and significant optic nerve damage."

Significant optic nerve damage in JOAG produces glaucomatous visual field loss; supports the visual field defect phenotype.

Myopia FREQUENT Myopia HP:0000545

Show evidence (2 references)

PMID:34536459 SUPPORT Human Clinical

"Myopia is a common association."

Identifies myopia as a common refractive association in JOAG.

PMID:37725790 SUPPORT Human Clinical

"Myopia and the number of baseline glaucoma medications were significantly associated with surgical failure."

Supports myopia as a clinically relevant JOAG association linked to surgical failure.

Other 3

Open-Angle Glaucoma Open angle glaucoma HP:0012108

Show evidence (1 reference)

PMID:34536459 SUPPORT Human Clinical

"Juvenile-onset open-angle glaucoma (JOAG) is a subset of primary open-angle glaucoma that is diagnosed before 40 years of age."

Establishes JOAG as an open-angle glaucoma diagnosed before 40 years of age.

Markedly Elevated Intraocular Pressure VERY_FREQUENT Ocular hypertension HP:0007906

Show evidence (1 reference)

PMID:34536459 SUPPORT Human Clinical

"JOAG is characterized by high intraocular pressures (IOP), with many patients needing surgery."

Identifies high IOP as a defining feature of JOAG, distinct from the more modest pressures often seen in adult POAG, and links it to the surgical management imperative.

Optic Nerve Cupping VERY_FREQUENT Increased cup-to-disc ratio HP:0012796

Show evidence (1 reference)

PMID:34536459 SUPPORT Human Clinical

"The unique optic nerve head features include large discs with deep, steep cupping associated with high IOP-induced damage."

Documents the characteristic deep, steep optic disc cupping of JOAG.

🧬

Genetic Associations

2

MYOC (Causative)

Gene: MYOC hgnc:7610 relationship_type: CAUSATIVE variant_origin: GERMLINE

Autosomal Dominant

Show evidence (3 references)

PMID:27080696 SUPPORT Human Clinical

"Pathogenic variants in the Myocilin gene (MYOC) cause juvenile open angle glaucoma (JOAG) in 8-36% of cases, and display an autosomal dominant inheritance with high penetrance."

Establishes MYOC as a causative gene for JOAG in 8-36% of cases with autosomal dominant, high-penetrance inheritance.

PMID:32300215 SUPPORT Human Clinical

"A 90% penetrance for the Gly367Arg variant was seen by the age of 40 years in our patients."

Quantifies high (90%) penetrance by age 40 for a specific MYOC variant in JOAG, supporting the high-penetrance autosomal dominant pattern.

PMID:27080696 SUPPORT Human Clinical

"This finding emphasizes the importance of screening individuals with JOAG for MYOC mutations irrespective of a negative family history."

Supports MYOC screening in JOAG regardless of family history, reflecting the occurrence of de novo variants in sporadic cases.

CYP1B1 (Causative)

Gene: CYP1B1 hgnc:2597 relationship_type: CAUSATIVE variant_origin: GERMLINE

Autosomal Recessive

Show evidence (2 references)

PMID:39998747 SUPPORT Human Clinical

"Analysis reveals a higher prevalence of CYP1B1 gene variants (22.5%) relative to MYOC gene variants (4.5%), suggesting that CYP1B1 is the predominant gene implicated in JOAG among Indian patients."

Establishes CYP1B1 as a causative gene for JOAG that can predominate over MYOC in specific populations.

PMID:32421983 PARTIAL Human Clinical

"PCG is classified as an autosomal recessive disorder involving four loci. The main culprit is CYP1B1, at locus GLC3A."

Supports CYP1B1 (GLC3A) as the principal recessive locus for developmental glaucoma; this gene also contributes to JOAG.

💊

Medical Actions

4

Topical IOP-Lowering Pharmacotherapy

Action: Pharmacotherapy NCIT:C15986

Topical pressure-lowering drops (e.g., prostaglandin analogs, beta-blockers) are typically first attempted, but in JOAG medical therapy alone is often insufficient to control the characteristically high IOP, and many patients progress to surgery.

Show evidence (1 reference)

PMID:34536459 PARTIAL Human Clinical

"JOAG is characterized by high intraocular pressures (IOP), with many patients needing surgery."

Indicates that medical therapy is frequently insufficient in JOAG and many patients require surgical intervention, contextualizing the role of topical pharmacotherapy.

Genetic Counseling

Action: Genetic Counseling NCIT:C15240

Genetic counseling is recommended for JOAG patients and at-risk family members, given autosomal dominant MYOC inheritance with high penetrance, documented de novo variants, and the importance of early detection through family screening irrespective of family history.

Show evidence (1 reference)

PMID:27080696 SUPPORT Human Clinical

"This finding emphasizes the importance of screening individuals with JOAG for MYOC mutations irrespective of a negative family history."

Supports genetic screening/counseling in JOAG irrespective of family history, given high-penetrance autosomal dominant MYOC inheritance and de novo variants.

Trabeculectomy with Mitomycin-C

Action: trabeculectomy MAXO:0001082

Incisional filtration surgery (commonly trabeculectomy augmented with mitomycin-C) is the most common primary surgery for JOAG, reflecting the surgery-first management imperative driven by high IOP poorly controlled medically. A substantial fraction of patients require additional surgery over long-term follow-up.

Show evidence (2 references)

PMID:37725790 SUPPORT Human Clinical

"Trabeculectomy with mitomycin C was the most common primary surgery performed in Thai patients with JOAG, and successfully reduced intraocular pressure without significant complications."

Supports trabeculectomy with mitomycin-C as the most common, effective primary surgery for JOAG.

PMID:37725790 SUPPORT Human Clinical

"By 10 years, half of the patients required additional surgery and risk factors for failure included myopia and the number of medications."

Documents that a substantial fraction of JOAG patients require additional surgery over long-term follow-up, reflecting disease severity.

Glaucoma Drainage / Shunt Surgery

Action: Surgical Procedure NCIT:C15329

Filtration shunt procedures (e.g., EX-PRESS mini glaucoma shunt with mitomycin-C) are alternative incisional options for early-onset glaucoma and may offer good IOP control in pediatric and juvenile glaucoma.

Show evidence (1 reference)

PMID:28146442 SUPPORT Human Clinical

"In this review, patients with pediatric glaucoma managed with EX-PRESS shunt with MMC compared with trabeculectomy with MMC appear to have better intraocular pressure control, better visual acuities, and fewer complications and reoperations."

Supports glaucoma shunt surgery (EX-PRESS with MMC) as an effective surgical option for early-onset (congenital/juvenile) glaucoma.

🔬

Biochemical Markers

1

Intraocular Pressure (Elevated)

Context: Characteristically high IOP, frequently exceeding the adult POAG range, often requiring surgery

Show evidence (1 reference)

PMID:34536459 SUPPORT Human Clinical

"JOAG is characterized by high intraocular pressures (IOP), with many patients needing surgery."

Supports markedly elevated IOP as the defining biochemical/clinical feature of JOAG.

{ }

Source YAML

click to show

name: Juvenile Open Angle Glaucoma
creation_date: "2026-06-08T00:00:00Z"
category: Mendelian
parents:
- Glaucoma
disease_term:
  preferred_term: juvenile open angle glaucoma
  term:
    id: MONDO:0020367
    label: juvenile open angle glaucoma
description: >
  Juvenile open-angle glaucoma (JOAG) is an early-onset subset of primary
  open-angle glaucoma diagnosed between approximately 3 and 40 years of age,
  bridging the gap between primary congenital glaucoma (onset before 3 years)
  and adult-onset POAG. It is clinically distinct from adult POAG: the
  drainage angle is open and grossly normal on gonioscopy, but the eye
  presents with markedly high intraocular pressure (frequently >30-40 mmHg),
  large optic discs with deep steep cupping, frequent myopia, and a strong
  tendency to require surgery rather than respond durably to topical drops.
  Most familial cases are autosomal dominant with high penetrance and are
  caused by myocilin (MYOC) mutations; in some populations CYP1B1 variants
  predominate. The underlying defect is immaturity/dysgenesis of the
  conventional (trabecular) aqueous outflow pathway. This entry is scoped to
  the juvenile-onset entity and its gene-linked subtypes, and deliberately
  does not re-derive the generic adult POAG content captured in Glaucoma.yaml.
has_subtypes:
- name: MYOC JOAG
  display_name: MYOC-related Juvenile Open-Angle Glaucoma
  description: >
    Autosomal dominant JOAG caused by mutations in myocilin (MYOC, the GLC1A
    locus), the most commonly identified genetic cause. Mutations cluster in
    the olfactomedin domain, are highly penetrant, and are associated with
    severe, surgery-prone glaucoma. Mutant myocilin misfolds and aggregates
    intracellularly in trabecular meshwork cells rather than being secreted,
    triggering ER stress and TM cell death with consequent IOP elevation.
- name: CYP1B1 JOAG
  display_name: CYP1B1-related Juvenile Open-Angle Glaucoma
  description: >
    JOAG associated with variants in cytochrome P450 1B1 (CYP1B1, the GLC3A
    locus classically implicated in primary congenital glaucoma). CYP1B1
    variants are typically recessive and contribute to anterior-segment /
    trabecular meshwork developmental dysgenesis; in some populations (e.g.,
    North Indian cohorts) CYP1B1 is the predominant gene implicated in JOAG,
    exceeding MYOC.
- name: Non-familial JOAG
  display_name: Sporadic / Non-familial Juvenile Open-Angle Glaucoma
  description: >
    JOAG occurring without an identifiable family history. A substantial
    fraction of sporadic cases have no MYOC mutation, and de novo MYOC
    variants have been documented, so screening is warranted irrespective of
    family history. Proportions of familial versus sporadic disease vary by
    population.
pathophysiology:
- name: Trabecular Meshwork Immaturity and Outflow Obstruction
  conforms_to: "glaucoma_optic_neuropathy#Trabecular Meshwork Outflow Dysfunction"
  downstream:
  - target: Pressure-Induced Glaucomatous Optic Neuropathy
  description: >
    The core lesion in JOAG is immaturity/dysgenesis of the conventional
    (trabecular) aqueous outflow pathway. Unlike acquired age-related
    trabecular dysfunction in adult POAG, the juvenile outflow apparatus is
    developmentally underdeveloped, producing high outflow resistance and
    markedly elevated intraocular pressure despite a grossly open and normal
    drainage angle.
  locations:
  - preferred_term: Eye Trabecular Meshwork
    term:
      id: UBERON:0005969
      label: eye trabecular meshwork
  - preferred_term: Iridocorneal Angle
    term:
      id: UBERON:0006206
      label: iridocorneal angle
  cell_types:
  - preferred_term: Trabecular Meshwork Cell
    term:
      id: CL:0002367
      label: trabecular meshwork cell
  biological_processes:
  - preferred_term: Trabecular Meshwork Development
    term:
      id: GO:0002930
      label: trabecular meshwork development
    modifier: ABNORMAL
  evidence:
  - reference: PMID:34536459
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The pathophysiology underlying the disease is immaturity of the conventional outflow pathways, which may or may not be observed on gonioscopy and anterior segment optical coherence tomography."
    explanation: >
      Identifies immaturity of the conventional (trabecular) outflow pathway
      as the central pathophysiology of JOAG, distinguishing it from acquired
      adult trabecular dysfunction.
  - reference: PMID:39998747
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Juvenile onset open-angle glaucoma (JOAG) manifests in individuals under the age of 40, resulting in elevated intraocular pressure and significant optic nerve damage."
    explanation: >
      Confirms that JOAG (onset under 40 years) is characterized by elevated
      IOP driven by outflow dysfunction with consequent optic nerve damage.
- name: Mutant Myocilin Misfolding and Trabecular Cell Stress
  conforms_to: "glaucoma_optic_neuropathy#Trabecular Meshwork Outflow Dysfunction"
  downstream:
  - target: Trabecular Meshwork Immaturity and Outflow Obstruction
  description: >
    In MYOC-related JOAG, mutations (predominantly in the olfactomedin domain)
    cause a gain of toxic function: mutant myocilin aggregates intracellularly
    in trabecular meshwork cells instead of being secreted. The resulting ER
    stress and unfolded-protein response causes an early, accelerated timeline
    of TM cell death, elevated IOP, and downstream glaucomatous optic
    neuropathy. The early-onset, severe phenotype of JOAG reflects the
    high-penetrance, toxic gain-of-function nature of these alleles.
  locations:
  - preferred_term: Eye Trabecular Meshwork
    term:
      id: UBERON:0005969
      label: eye trabecular meshwork
  cell_types:
  - preferred_term: Trabecular Meshwork Cell
    term:
      id: CL:0002367
      label: trabecular meshwork cell
  biological_processes:
  - preferred_term: Endoplasmic Reticulum Unfolded Protein Response
    term:
      id: GO:0030968
      label: endoplasmic reticulum unfolded protein response
    modifier: INCREASED
  - preferred_term: Protein Folding
    term:
      id: GO:0006457
      label: protein folding
    modifier: ABNORMAL
  - preferred_term: Apoptotic Process
    term:
      id: GO:0006915
      label: apoptotic process
    modifier: INCREASED
  evidence:
  - reference: PMID:37217093
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "The prevailing pathogenic mechanism involves a gain of toxic function whereby mutant myocilin aggregates intracellularly instead of being secreted, which causes cell stress and an early timeline for TM cell death, elevated intraocular pressure, and subsequent glaucoma-associated retinal degeneration."
    explanation: >
      Describes the myocilin gain-of-toxic-function mechanism: intracellular
      aggregation, TM cell stress and early death, elevated IOP, and
      glaucomatous degeneration, which underlies the severe early-onset
      MYOC-JOAG phenotype.
  - reference: PMID:37217093
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: "While myocilin is expressed in numerous tissues, mutant myocilin is only associated with disease in the anterior segment of the eye, in the trabecular meshwork."
    explanation: >
      Establishes that mutant myocilin pathology is restricted to the
      trabecular meshwork of the anterior segment, the site of outflow
      obstruction in JOAG.
- name: Anterior-Segment / Trabecular Dysgenesis in CYP1B1-related Disease
  conforms_to: "glaucoma_optic_neuropathy#Trabecular Meshwork Outflow Dysfunction"
  downstream:
  - target: Trabecular Meshwork Immaturity and Outflow Obstruction
  description: >
    In CYP1B1-related JOAG, recessive variants in cytochrome P450 1B1 (GLC3A)
    impair normal development of the eye's aqueous outflow system, producing
    trabeculodysgenesis and anterior-chamber angle developmental
    abnormalities that obstruct aqueous outflow and elevate IOP. CYP1B1 is the
    classic primary congenital glaucoma gene, and its involvement in JOAG
    links juvenile-onset disease to a developmental, dysgenetic mechanism
    rather than purely degenerative outflow failure.
  locations:
  - preferred_term: Eye Trabecular Meshwork
    term:
      id: UBERON:0005969
      label: eye trabecular meshwork
  - preferred_term: Anterior Chamber of Eyeball
    term:
      id: UBERON:0001766
      label: anterior chamber of eyeball
  biological_processes:
  - preferred_term: Trabecular Meshwork Development
    term:
      id: GO:0002930
      label: trabecular meshwork development
    modifier: ABNORMAL
  - preferred_term: Eye Development
    term:
      id: GO:0001654
      label: eye development
    modifier: ABNORMAL
  evidence:
  - reference: PMID:39998747
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Analysis reveals a higher prevalence of CYP1B1 gene variants (22.5%) relative to MYOC gene variants (4.5%), suggesting that CYP1B1 is the predominant gene implicated in JOAG among Indian patients."
    explanation: >
      Demonstrates that CYP1B1 variants can be the predominant genetic cause
      of JOAG in some populations, supporting CYP1B1-related developmental
      dysgenesis as a distinct JOAG subtype mechanism.
  - reference: PMID:32421983
    supports: PARTIAL
    evidence_source: HUMAN_CLINICAL
    snippet: "It is caused by genetic structural defects in the trabecular meshwork and makes its appearence in newborns and children no older than three years."
    explanation: >
      Establishes CYP1B1 (the GLC3A locus) as causing trabecular meshwork
      structural/developmental defects; this developmental dysgenesis
      mechanism extends to CYP1B1-related juvenile-onset disease.
- name: Pressure-Induced Glaucomatous Optic Neuropathy
  conforms_to: "glaucoma_optic_neuropathy#Retinal Ganglion Cell Apoptosis"
  description: >
    Sustained, markedly elevated IOP in JOAG causes mechanical and ischemic
    stress on the optic nerve head, producing retinal ganglion cell loss and
    characteristic large discs with deep, steep cupping. Because the disease
    affects young patients, the cumulative lifetime burden of optic nerve
    damage and projected disability is higher than in adult-onset glaucoma.
  locations:
  - preferred_term: Optic Disc
    term:
      id: UBERON:0001783
      label: optic disc
  - preferred_term: Retina
    term:
      id: UBERON:0000966
      label: retina
  cell_types:
  - preferred_term: Retinal Ganglion Cell
    term:
      id: CL:0000740
      label: retinal ganglion cell
  biological_processes:
  - preferred_term: Apoptotic Process
    term:
      id: GO:0006915
      label: apoptotic process
    modifier: INCREASED
  evidence:
  - reference: PMID:34536459
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The unique optic nerve head features include large discs with deep, steep cupping associated with high IOP-induced damage."
    explanation: >
      Documents the distinctive JOAG optic nerve head phenotype (large discs,
      deep steep cupping) driven by high IOP-induced damage.
  - reference: PMID:34536459
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Progression rates among JOAG patients are comparable to adult primary glaucomas, but as the disease affects younger patients, the projected disability from this disease is higher."
    explanation: >
      Supports the higher projected lifetime disability of JOAG due to early
      onset, motivating aggressive management of the optic neuropathy.
phenotypes:
- name: Open-Angle Glaucoma
  category: Ophthalmological
  diagnostic: true
  description: Glaucoma with an open, grossly normal drainage angle on gonioscopy, diagnosed in juvenile-onset patients.
  phenotype_term:
    preferred_term: Open angle glaucoma
    term:
      id: HP:0012108
      label: Open angle glaucoma
  evidence:
  - reference: PMID:34536459
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Juvenile-onset open-angle glaucoma (JOAG) is a subset of primary open-angle glaucoma that is diagnosed before 40 years of age."
    explanation: Establishes JOAG as an open-angle glaucoma diagnosed before 40 years of age.
- name: Markedly Elevated Intraocular Pressure
  category: Ophthalmological
  frequency: VERY_FREQUENT
  diagnostic: true
  description: High intraocular pressure, frequently substantially above the adult POAG range, is a hallmark of JOAG.
  phenotype_term:
    preferred_term: Ocular hypertension
    term:
      id: HP:0007906
      label: Ocular hypertension
  evidence:
  - reference: PMID:34536459
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "JOAG is characterized by high intraocular pressures (IOP), with many patients needing surgery."
    explanation: >
      Identifies high IOP as a defining feature of JOAG, distinct from the
      more modest pressures often seen in adult POAG, and links it to the
      surgical management imperative.
- name: Optic Nerve Cupping
  category: Ophthalmological
  frequency: VERY_FREQUENT
  diagnostic: true
  description: Large optic discs with deep, steep cupping reflecting glaucomatous optic neuropathy.
  phenotype_term:
    preferred_term: Optic disc cupping
    term:
      id: HP:0012796
      label: Increased cup-to-disc ratio
  evidence:
  - reference: PMID:34536459
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The unique optic nerve head features include large discs with deep, steep cupping associated with high IOP-induced damage."
    explanation: Documents the characteristic deep, steep optic disc cupping of JOAG.
- name: Visual Field Loss
  category: Ophthalmological
  frequency: FREQUENT
  description: Progressive glaucomatous visual field defects from retinal ganglion cell loss.
  phenotype_term:
    preferred_term: Visual field defect
    term:
      id: HP:0001123
      label: Visual field defect
  evidence:
  - reference: PMID:39998747
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Juvenile onset open-angle glaucoma (JOAG) manifests in individuals under the age of 40, resulting in elevated intraocular pressure and significant optic nerve damage."
    explanation: >
      Significant optic nerve damage in JOAG produces glaucomatous visual
      field loss; supports the visual field defect phenotype.
- name: Myopia
  category: Ophthalmological
  frequency: FREQUENT
  description: Myopia is a common refractive association in JOAG and is linked to surgical failure.
  phenotype_term:
    preferred_term: Myopia
    term:
      id: HP:0000545
      label: Myopia
  evidence:
  - reference: PMID:34536459
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Myopia is a common association."
    explanation: Identifies myopia as a common refractive association in JOAG.
  - reference: PMID:37725790
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Myopia and the number of baseline glaucoma medications were significantly associated with surgical failure."
    explanation: Supports myopia as a clinically relevant JOAG association linked to surgical failure.
biochemical:
- name: Intraocular Pressure
  presence: Elevated
  context: "Characteristically high IOP, frequently exceeding the adult POAG range, often requiring surgery"
  evidence:
  - reference: PMID:34536459
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "JOAG is characterized by high intraocular pressures (IOP), with many patients needing surgery."
    explanation: Supports markedly elevated IOP as the defining biochemical/clinical feature of JOAG.
genetic:
- name: MYOC
  association: Causative
  relationship_type: CAUSATIVE
  variant_origin: GERMLINE
  notes: >
    GLC1A locus; most commonly identified genetic cause of JOAG. Mutations
    cluster in the olfactomedin domain and act through a toxic gain-of-function
    mechanism. De novo MYOC variants occur, so screening is warranted even
    without a family history.
  inheritance:
  - name: Autosomal Dominant
    inheritance_term:
      preferred_term: Autosomal dominant inheritance
      term:
        id: HP:0000006
        label: Autosomal dominant inheritance
    penetrance: INCOMPLETE
  gene_term:
    preferred_term: MYOC
    term:
      id: hgnc:7610
      label: MYOC
  evidence:
  - reference: PMID:27080696
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Pathogenic variants in the Myocilin gene (MYOC) cause juvenile open angle glaucoma (JOAG) in 8-36% of cases, and display an autosomal dominant inheritance with high penetrance."
    explanation: >
      Establishes MYOC as a causative gene for JOAG in 8-36% of cases with
      autosomal dominant, high-penetrance inheritance.
  - reference: PMID:32300215
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "A 90% penetrance for the Gly367Arg variant was seen by the age of 40 years in our patients."
    explanation: >
      Quantifies high (90%) penetrance by age 40 for a specific MYOC variant
      in JOAG, supporting the high-penetrance autosomal dominant pattern.
  - reference: PMID:27080696
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "This finding emphasizes the importance of screening individuals with JOAG for MYOC mutations irrespective of a negative family history."
    explanation: >
      Supports MYOC screening in JOAG regardless of family history, reflecting
      the occurrence of de novo variants in sporadic cases.
- name: CYP1B1
  association: Causative
  relationship_type: CAUSATIVE
  variant_origin: GERMLINE
  notes: >
    GLC3A locus; classically the primary congenital glaucoma gene. CYP1B1
    variants are typically recessive and can be the predominant cause of JOAG
    in some populations (e.g., North Indian cohorts), contributing to
    anterior-segment/trabecular developmental dysgenesis.
  inheritance:
  - name: Autosomal Recessive
    inheritance_term:
      preferred_term: Autosomal recessive inheritance
      term:
        id: HP:0000007
        label: Autosomal recessive inheritance
  gene_term:
    preferred_term: CYP1B1
    term:
      id: hgnc:2597
      label: CYP1B1
  evidence:
  - reference: PMID:39998747
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Analysis reveals a higher prevalence of CYP1B1 gene variants (22.5%) relative to MYOC gene variants (4.5%), suggesting that CYP1B1 is the predominant gene implicated in JOAG among Indian patients."
    explanation: >
      Establishes CYP1B1 as a causative gene for JOAG that can predominate
      over MYOC in specific populations.
  - reference: PMID:32421983
    supports: PARTIAL
    evidence_source: HUMAN_CLINICAL
    snippet: "PCG is classified as an autosomal recessive disorder involving four loci. The main culprit is CYP1B1, at locus GLC3A."
    explanation: >
      Supports CYP1B1 (GLC3A) as the principal recessive locus for
      developmental glaucoma; this gene also contributes to JOAG.
treatments:
- name: Topical IOP-Lowering Pharmacotherapy
  description: >
    Topical pressure-lowering drops (e.g., prostaglandin analogs, beta-blockers)
    are typically first attempted, but in JOAG medical therapy alone is often
    insufficient to control the characteristically high IOP, and many patients
    progress to surgery.
  context: Initial medical management, frequently inadequate for durable control in JOAG
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
  evidence:
  - reference: PMID:34536459
    supports: PARTIAL
    evidence_source: HUMAN_CLINICAL
    snippet: "JOAG is characterized by high intraocular pressures (IOP), with many patients needing surgery."
    explanation: >
      Indicates that medical therapy is frequently insufficient in JOAG and
      many patients require surgical intervention, contextualizing the role of
      topical pharmacotherapy.
- name: Genetic Counseling
  description: >
    Genetic counseling is recommended for JOAG patients and at-risk family
    members, given autosomal dominant MYOC inheritance with high penetrance,
    documented de novo variants, and the importance of early detection through
    family screening irrespective of family history.
  context: Family screening and risk communication for gene-linked JOAG
  treatment_term:
    preferred_term: Genetic Counseling
    term:
      id: NCIT:C15240
      label: Genetic Counseling
  evidence:
  - reference: PMID:27080696
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "This finding emphasizes the importance of screening individuals with JOAG for MYOC mutations irrespective of a negative family history."
    explanation: >
      Supports genetic screening/counseling in JOAG irrespective of family
      history, given high-penetrance autosomal dominant MYOC inheritance and de
      novo variants.
- name: Trabeculectomy with Mitomycin-C
  description: >
    Incisional filtration surgery (commonly trabeculectomy augmented with
    mitomycin-C) is the most common primary surgery for JOAG, reflecting the
    surgery-first management imperative driven by high IOP poorly controlled
    medically. A substantial fraction of patients require additional surgery
    over long-term follow-up.
  context: Primary surgical management for medically uncontrolled JOAG
  treatment_term:
    preferred_term: trabeculectomy
    term:
      id: MAXO:0001082
      label: trabeculectomy
  evidence:
  - reference: PMID:37725790
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Trabeculectomy with mitomycin C was the most common primary surgery performed in Thai patients with JOAG, and successfully reduced intraocular pressure without significant complications."
    explanation: >
      Supports trabeculectomy with mitomycin-C as the most common, effective
      primary surgery for JOAG.
  - reference: PMID:37725790
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "By 10 years, half of the patients required additional surgery and risk factors for failure included myopia and the number of medications."
    explanation: >
      Documents that a substantial fraction of JOAG patients require
      additional surgery over long-term follow-up, reflecting disease severity.
- name: Glaucoma Drainage / Shunt Surgery
  description: >
    Filtration shunt procedures (e.g., EX-PRESS mini glaucoma shunt with
    mitomycin-C) are alternative incisional options for early-onset glaucoma
    and may offer good IOP control in pediatric and juvenile glaucoma.
  context: Surgical alternative to trabeculectomy in congenital/juvenile glaucoma
  treatment_term:
    preferred_term: Surgical Procedure
    term:
      id: NCIT:C15329
      label: Surgical Procedure
  evidence:
  - reference: PMID:28146442
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "In this review, patients with pediatric glaucoma managed with EX-PRESS shunt with MMC compared with trabeculectomy with MMC appear to have better intraocular pressure control, better visual acuities, and fewer complications and reoperations."
    explanation: >
      Supports glaucoma shunt surgery (EX-PRESS with MMC) as an effective
      surgical option for early-onset (congenital/juvenile) glaucoma.
diagnosis:
- name: Tonometry (Intraocular Pressure Measurement)
  description: >
    Measurement of intraocular pressure is central to JOAG diagnosis and
    monitoring; affected patients characteristically show markedly elevated IOP.
  diagnosis_term:
    preferred_term: tonometry
    term:
      id: MAXO:0000974
      label: tonometry
  evidence:
  - reference: PMID:34536459
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "JOAG is characterized by high intraocular pressures (IOP), with many patients needing surgery."
    explanation: >
      High intraocular pressure is the measurable hallmark of JOAG, making
      tonometry a core diagnostic and monitoring modality.
- name: Gonioscopy and Anterior Segment Optical Coherence Tomography
  description: >
    Gonioscopy confirms an open, grossly normal drainage angle (distinguishing
    JOAG from angle-closure and overt anterior-segment dysgenesis), and
    anterior segment OCT can reveal immaturity of the conventional outflow
    pathway.
  diagnosis_term:
    preferred_term: gonioscopy
    term:
      id: MAXO:0000970
      label: gonioscopy
  evidence:
  - reference: PMID:34536459
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "The pathophysiology underlying the disease is immaturity of the conventional outflow pathways, which may or may not be observed on gonioscopy and anterior segment optical coherence tomography."
    explanation: >
      Establishes gonioscopy and anterior segment OCT as the diagnostic
      modalities used to assess the conventional outflow pathway in JOAG.
classifications:
  harrisons_chapter:
  - classification_value: NEUROLOGIC
datasets:
references:
- reference: PMID:34536459
  title: "Juvenile-onset open-angle glaucoma - A clinical and genetic update."
- reference: PMID:9005853
  title: "Identification of a gene that causes primary open angle glaucoma."

📚

References & Deep Research

References

2

PMID:34536459

Juvenile-onset open-angle glaucoma - A clinical and genetic update.

No top-level findings curated for this source.

PMID:9005853

Identification of a gene that causes primary open angle glaucoma.

No top-level findings curated for this source.

Deep Research

1

Falcon ▸

Juvenile Open-Angle Glaucoma (JOAG) — Disease Characteristics Research Report

Edison Scientific Literature 30 citations 2026-06-08T10:40:00.560080

Juvenile Open-Angle Glaucoma (JOAG) — Disease Characteristics Research Report

Target disease: Juvenile open-angle glaucoma (JOAG)
MONDO: MONDO:0020367 (via OpenTargets disease mapping) (OpenTargets Search: juvenile open angle glaucoma)
Category: Mendelian (early-onset glaucoma frequently follows Mendelian inheritance) (pan2024exploringthegenetic pages 1-2)

Executive overview (current understanding)

Juvenile open-angle glaucoma (JOAG) is a primary childhood/early-onset open-angle glaucoma characterized by elevated intraocular pressure (IOP), glaucomatous optic neuropathy, and corresponding visual field defects, typically presenting in childhood, adolescence, or young adulthood, classically before age 40 (or sometimes before ~35 in certain definitions). It differs from primary congenital glaucoma by the absence of congenital anterior-segment abnormalities (e.g., Haab striae, enlarged corneal diameter, anterior segment dysgenesis) and by a later onset, yet it often shows more severe IOP elevation and faster progression than typical adult-onset primary open-angle glaucoma (POAG). (almulhim2024agesexand pages 1-2, huang2018detectionofmutations pages 1-2, pan2024exploringthegenetic pages 9-11)

1. Disease information

1.1 Definition and overview

A recent childhood glaucoma genetics review describes a modern consensus classification in which childhood glaucoma is divided into primary vs secondary forms, and primary childhood glaucoma includes primary congenital glaucoma (PCG) and JOAG. In this framework, JOAG may be asymptomatic and identified incidentally or during family screening. (pan2024exploringthegenetic pages 1-2)

Clinical definition used in recent JOAG cohorts: * Saudi tertiary-center cohort (2015–2022) defined inclusion as symptom onset between 3 and 40 years, glaucomatous optic neuropathy with compatible visual field loss, persistent elevated IOP (>22 mmHg on ≥2 occasions), and open angles. (almulhim2024agesexand pages 2-4)

1.2 Key identifiers

MONDO: MONDO:0020367 (OpenTargets mapping) (OpenTargets Search: juvenile open angle glaucoma)
Other identifiers (OMIM/Orphanet/ICD/MeSH): not directly retrievable from the accessible full-text sources in this run; should be added from OMIM/Orphanet/ICD/MeSH authoritative records in a subsequent curation pass.

1.3 Synonyms / alternative names

Commonly used terms in the literature include: * “juvenile open-angle glaucoma (JOAG)” (almulhim2024agesexand pages 1-2, pan2024exploringthegenetic pages 1-2) * “juvenile-onset open-angle glaucoma” (JOAG) (huang2018detectionofmutations pages 1-2) * “juvenile-onset primary open-angle glaucoma” (juvenile-onset POAG) (huang2018detectionofmutations pages 1-2)

1.4 Evidence type

The information below is derived from: * Aggregated disease-level resources/reviews (systematic review; narrative reviews) (kumar2024geneticchangesand pages 1-2, pan2024exploringthegenetic pages 1-2) * Human clinical cohorts/case series (retrospective cohorts and surgical series) (almulhim2024agesexand pages 5-7, un2024surgicalapproachesto pages 1-2) * Human genetics case report (de novo MYOC variant) (souzeau2016anovelde pages 2-5) * In vitro / biochemical variant interpretation (MYOC olfactomedin-domain assays) (scelsi2023quantitativedifferentiationof pages 1-3)

2. Etiology

2.1 Disease causal factors (primary causes)

JOAG is predominantly genetic and is classically considered a Mendelian disorder in early-onset glaucoma; one review notes: “early-onset cases (before 40 years) typically displaying Mendelian inheritance patterns”. (pan2024exploringthegenetic pages 1-2)

Causal genetic factors are most strongly supported for MYOC (myocilin) in autosomal dominant JOAG, with additional genes sometimes implicated in juvenile/early-onset open-angle glaucoma phenotypes (e.g., CYP1B1, OPTN, FOXC1; and biallelic CPAMD8 in some childhood/juvenile open-angle glaucoma cases). (OpenTargets Search: juvenile open angle glaucoma, huang2018detectionofmutations pages 1-2, kumar2024geneticchangesand pages 1-2, pan2024exploringthegenetic pages 9-11)

2.2 Risk factors

Genetic risk factors * MYOC pathogenic variants: A 2024 systematic review of childhood glaucoma genetics reports: “MYOC variants … with prevalence up to 36% among patients with juvenile open angle glaucoma.” (kumar2024geneticchangesand pages 1-2) * A Saudi JOAG cohort review within a clinical cohort paper notes MYOC mutations were found in ~3.6–9.5% of JOAG patients (literature figure cited within that paper). (almulhim2024agesexand pages 1-2)

Non-genetic / demographic risk factors JOAG is frequently associated with myopia and family history in clinic-based cohorts (see Phenotypes and Epidemiology below), but robust, JOAG-specific environmental risk factor quantification was not available in the retrieved corpus.

2.3 Protective factors

JOAG-specific protective factors were not identified from the retrieved sources. (No relevant evidence in current corpus.)

2.4 Gene–environment interactions

No JOAG-specific gene–environment interaction evidence was identified in the retrieved sources. (No relevant evidence in current corpus.)

3. Phenotypes

3.1 Core clinical phenotype (human)

Hallmarks: elevated IOP with glaucomatous optic nerve damage and corresponding visual field defects in an anatomically open angle. (almulhim2024agesexand pages 2-4, pan2024exploringthegenetic pages 1-2)

Severity: A 2024 review states JOAG is characterized by “extremely elevated IOP, often exceeding 50 mmHg, necessitating surgical treatment” and is inherited as an autosomal dominant trait. (pan2024exploringthegenetic pages 9-11)

Cohort phenotype statistics (Saudi, 2015–2022): * Mean age 26.91 years; range 6–38 (45 patients; 87 eyes) (almulhim2024agesexand pages 2-4) * Bilateral disease: 93.3% (42/45) (almulhim2024agesexand pages 2-4) * Myopia: 93.3% (42/45) (almulhim2024agesexand pages 4-5) * Family history of glaucoma: 51.1% (23/45) (almulhim2024agesexand pages 4-5) * Optic nerve: mean cup–disc ratio 0.73±0.14 (OD) and 0.66±0.17 (OS) (almulhim2024agesexand pages 2-4) * Visual field severity: severe defects in 57.1% (OD) and 44.4% (OS) (almulhim2024agesexand pages 4-5)

Suggested HPO terms (examples; not exhaustive): * Elevated intraocular pressure — HP:0000506 * Glaucomatous optic disc cupping — HP:0030539 (or Optic disc cupping) * Visual field defect — HP:0001123 * Retinal nerve fiber layer thinning (OCT) — HP:0030791 (if used) * Myopia — HP:0000545

3.2 Quality-of-life impact

Direct JOAG-specific QoL instruments (EQ-5D, VFQ-25, etc.) were not located in the retrieved sources. However, JOAG can cause substantial irreversible vision loss through severe early visual field defects, implying significant functional impact. (almulhim2024agesexand pages 1-2, almulhim2024agesexand pages 4-5)

4. Genetic / molecular information

4.1 Causal genes (and evidence)

MYOC (myocilin) * A 2024 review explicitly states: “genes … associated with PCG; and MYOC (myocilin), associated with JOAG.” (pan2024exploringthegenetic pages 1-2) * JOAG genetic loci include GLC1A (contains MYOC) and others (GLC1J/K/M/N) (pan2024exploringthegenetic pages 9-11)

Other genes reported in JOAG / juvenile-onset open-angle glaucoma contexts * CYP1B1 and OPTN in a Chinese JOAG exome-sequenced cohort (huang2018detectionofmutations pages 1-2) * FOXC1 and other childhood glaucoma genes are discussed for pediatric glaucoma; FOXC1 is referenced as relevant in childhood glaucoma and may be seen in early-onset glaucomas (kumar2024geneticchangesand pages 1-2, pan2024exploringthegenetic pages 1-2) * OpenTargets also links MONDO:0020367 to MYOC, CYP1B1, FOXC1, and others (disease–target association view) (OpenTargets Search: juvenile open angle glaucoma)

4.2 Pathogenic variants (examples from primary literature)

MYOC variant spectrum * Review synthesis (2024): “over 250 MYOC mutations” have been reported; “37.7% are considered pathogenic”; and “approximately 97% of disease-causing MYOC mutations localize to exon 3” (and it references myocilin.com). (pan2024exploringthegenetic pages 9-11) * Key alleles highlighted for JOAG include p.Gln368stop (aggregation), p.Pro370Leu (severe), and p.Tyr437His (earlier onset, higher IOP) (pan2024exploringthegenetic pages 9-11)

Example JOAG variants identified via exome sequencing (Chinese cohort, n=67) * Heterozygous MYOC: c.1109C>T (p.P370L); c.1150G>C (p.D384H) * Heterozygous OPTN: c.985A>G (p.R329G); c.1481T>G (p.L494W) * Homozygous CYP1B1: c.1412T>G (p.I471S); c.1169G>A (p.R390H) (huang2018detectionofmutations pages 1-2)

De novo MYOC in sporadic JOAG * A case report identified a de novo MYOC:c.761C>T, p.(Pro254Leu) in a 14-year-old male with sporadic JOAG and no family history, emphasizing that MYOC testing can be relevant even without family history. (souzeau2016anovelde pages 2-5)

4.3 Inheritance, penetrance, expressivity

JOAG is described as autosomal dominant in the 2024 review and is commonly framed as a Mendelian early-onset disorder. (pan2024exploringthegenetic pages 1-2, pan2024exploringthegenetic pages 9-11)
Variable penetrance/expressivity is noted broadly for childhood glaucoma Mendelian genes (“strong penetrance but variable expressivity”), but JOAG-specific penetrance estimates were not available from the accessible full text in this run. (pan2024exploringthegenetic pages 1-2)

4.4 Functional consequences and variant interpretation (recent development)

A 2023 Disease Models & Mechanisms study positions MYOC-associated open-angle glaucoma as a toxic gain-of-function driven by misfolding/aggregation and provides a precision-medicine approach for variant interpretation: * “Inherited missense mutations in the myocilin (MYOC) gene … constitute the strongest genetic link to primary open-angle glaucoma via a toxic gain of function” (scelsi2023quantitativedifferentiationof pages 1-3) * It proposes a single biophysical discriminator: “pathogenicity can be predicted by a thermal stability cutoff of 47 °C” for the olfactomedin domain, supporting improved classification of rare MYOC variants seen in population databases. (scelsi2023quantitativedifferentiationof pages 1-3)

5. Environmental information

JOAG is principally a genetic disease entity in the retrieved sources. No JOAG-specific environmental toxins, infectious triggers, or protective lifestyle factors were identified in the retrieved corpus. (No relevant evidence in current corpus.)

6. Mechanism / pathophysiology

6.1 Causal chain (MYOC-centered, current consensus)

Upstream trigger: germline MYOC pathogenic variant (dominant; toxic gain-of-function) (scelsi2023quantitativedifferentiationof pages 1-3, pan2024exploringthegenetic pages 9-11)
Molecular mechanism: misfolding/aberrant trafficking → ER retention/accumulation → unfolded protein response (UPR) → ER stress → trabecular meshwork (TM) dysfunction/cell death (pan2024exploringthegenetic pages 9-11)
Tissue-level effect: reduced aqueous humor outflow through TM/Schlemm’s canal pathways → sustained IOP elevation (pan2024exploringthegenetic pages 9-11)
Clinical manifestations: optic nerve head damage (cupping/notching), retinal nerve fiber layer loss, progressive visual field defects (almulhim2024agesexand pages 2-4, souzeau2016anovelde pages 2-5)

A 2024 review states: “mutated MYOC tends to accumulate in the endoplasmic reticulum (ER) rather than proper release, leading to activation of the unfolded protein response (UPR) and subsequent ER stress”, and that TM cells may die, “thereby contributing to elevated IOP and the development of glaucoma.” (pan2024exploringthegenetic pages 9-11)

6.2 Pathways, cell types, and ontology suggestions

Key cell types (CL): * Trabecular meshwork cell — suggested (Cell Ontology term usage varies; may map to TM cell types) * Schlemm’s canal endothelial cell — suggested * Retinal ganglion cell — CL:0000740 (primary neurodegeneration target)

Biological processes (GO) – suggested: * Unfolded protein response — GO:0030968 * Response to endoplasmic reticulum stress — GO:0034976 * Protein folding / proteostasis — GO:0006457 * Apoptotic process — GO:0006915 * Regulation of intraocular pressure — suggested process mapping

7. Anatomical structures affected

Primary ocular structures (UBERON suggestions): * Trabecular meshwork (aqueous outflow) — UBERON:0001769 (commonly used) * Schlemm’s canal — UBERON:0001797 (commonly used) * Optic nerve head / optic disc — UBERON mapping dependent on use case * Retina / retinal nerve fiber layer; retinal ganglion cells — UBERON mappings

JOAG is defined by open angles and glaucomatous optic neuropathy with visual field loss, consistent with primary involvement of aqueous outflow tissues and retinal ganglion cell/optic nerve structures. (pan2024exploringthegenetic pages 1-2, almulhim2024agesexand pages 2-4)

8. Temporal development

Onset: childhood to young adulthood; commonly defined as onset/diagnosis between ages 3–40; some reviews describe occurrence “before the age of 35.” (almulhim2024agesexand pages 2-4, pan2024exploringthegenetic pages 9-11)

Course/progression: often progressive with severe IOP elevation and significant visual field loss at presentation in clinic-based cohorts; may be asymptomatic early. (pan2024exploringthegenetic pages 1-2, almulhim2024agesexand pages 4-5)

9. Inheritance and population

9.1 Epidemiology (recently extracted quantitative data)

Estimates vary substantially by setting: * A 2024 Ethiopian tertiary-center childhood glaucoma cohort reported JOAG = 15.5% of glaucomatous eyes (28/181; 95% CI 10.5–21.6). (mulugeta2024childhoodglaucomaprofile pages 1-3) * A 2024 surgical JOAG series reports JOAG as ~0.7% of glaucoma referrals in Caucasians and 3.3% of glaucoma admissions in a tertiary Indian center (as literature context). (un2024surgicalapproachesto pages 1-2) * A registry-oriented summary text reports: “The occurrence of JOAG is estimated at 1 in 50,000 individuals in the United States” (literature-cited figure within that text). (diel2024resultsofa pages 23-26)

9.2 Inheritance pattern

Often autosomal dominant for MYOC-driven JOAG; early-onset glaucoma is described as typically Mendelian. (pan2024exploringthegenetic pages 1-2, pan2024exploringthegenetic pages 9-11)

9.3 Founder effects / population-specific variants

The retrieved corpus did not provide robust, quantified founder-effect estimates for JOAG variants. However, MYOC p.Gln368stop is highlighted as a common mutation in JOAG. (pan2024exploringthegenetic pages 9-11)

10. Diagnostics

10.1 Clinical diagnostic criteria and tests

CGRN childhood glaucoma criteria (applies to childhood glaucoma diagnosis broadly): diagnosis requires ≥2 of: 1) IOP ≥21 mmHg
2) glaucomatous optic nerve damage (cupping/notching/C:D asymmetry ≥0.2)
3) corneal changes (e.g., increased corneal diameter or Haab striae)
4) visual field defects consistent with glaucomatous optic nerve damage
(pan2024exploringthegenetic pages 1-2)

Common clinical evaluations in JOAG cohorts: * Gold-standard IOP measurement series (thresholds >21 or >22 depending on protocol) (almulhim2024agesexand pages 2-4) * Gonioscopy confirming open angles (almulhim2024agesexand pages 2-4) * Visual fields (Humphrey 24-2 SITA standard in the Saudi cohort) (almulhim2024agesexand pages 2-4) * Optic nerve evaluation (cup–disc ratio) (almulhim2024agesexand pages 2-4)

Differential diagnosis considerations (from cohort definition logic): * Primary congenital glaucoma / anterior segment dysgenesis glaucomas (distinguished by corneal enlargement, Haab striae, abnormal anterior segment) (almulhim2024agesexand pages 1-2, pan2024exploringthegenetic pages 1-2) * Secondary glaucomas (e.g., steroid-induced, post-surgical) in pediatric populations (mulugeta2024childhoodglaucomaprofile pages 1-3)

10.2 Genetic testing (current state)

A 2024 systematic review emphasizes that testing practices are variable and that multiple genes are implicated; it reports that MYOC variants can be detected in up to 36% of JOAG in the literature, supporting MYOC-first or panel-based approaches in early-onset open-angle glaucoma. (kumar2024geneticchangesand pages 1-2)

Suggested approach (evidence-informed): 1) MYOC sequencing (coding + splice regions), with attention to exon 3/olfactomedin domain enrichment in pathogenic variants (pan2024exploringthegenetic pages 9-11) 2) If negative or phenotype suggests broader etiology, consider multi-gene childhood glaucoma / early-onset glaucoma panel including CYP1B1, OPTN, FOXC1 (and others per contemporary panels) (huang2018detectionofmutations pages 1-2, kumar2024geneticchangesand pages 1-2) 3) Consider exome/genome sequencing in unsolved cases (as demonstrated by JOAG exome cohort studies) (huang2018detectionofmutations pages 1-2)

11. Outcome / prognosis

JOAG often presents with severe visual field defects in clinic-based series, reflecting potentially advanced disease at first diagnosis and risk for irreversible vision loss if untreated. In the Saudi cohort, severe visual field defects were common (44–57% of eyes), implying substantial morbidity. (almulhim2024agesexand pages 4-5)

Long-term JOAG-specific survival/mortality is not applicable; vision-related outcomes dominate prognosis. Robust, multi-year JOAG progression models were not available in the retrieved sources.

12. Treatment

12.1 Current applications and real-world implementations

IOP lowering is the principal modifiable factor, achieved with topical medications and frequently surgery in JOAG.

Real-world cohort outcomes (Saudi, 2015–2022): * Surgical group: mean IOP decreased from 30.58±7.10 to 14.92 mmHg (p<0.01). (almulhim2024agesexand pages 5-7) * Non-surgical group: mean IOP decreased from 32.97±6.36 to 13.50 mmHg (p<0.01). (almulhim2024agesexand pages 5-7)

Surgical case series (2019–2022): multiple approaches were used: trabeculectomy with antimetabolite, glaucoma drainage device (Ahmed valve), deep sclerectomy/external trabeculotomy, and gonioscopy-assisted transluminal trabeculotomy (GATT). IOP fell from 27.62±7.17 to 17.62±13.06 mmHg, and 76.9% achieved IOP control without additional surgery during mean 15.6 months follow-up. (un2024surgicalapproachesto pages 1-2)

Modern Schlemm’s canal/outflow surgery (GATT) outcomes (3-year, 2025 study; included for completeness): * IOP decreased from 29.89±9.43 mmHg pre-op to 15.70±4.39 at 12 months and 17.33±3.37 at 36 months; complete success declined from 73.7% (12 mo) to 51.7% (36 mo). (hu2025threeyearoutcomesof pages 1-2)

12.2 MAXO terms (suggested)

Topical intraocular pressure–lowering therapy — MAXO:0000742 (approximate; verify exact MAXO mapping)
Trabeculectomy — MAXO term for trabeculectomy (ontology mapping required)
Glaucoma drainage device implantation — MAXO term
Trabeculotomy / GATT — MAXO term

12.3 Expert opinion / analysis (authoritative synthesis)

A 2024 genetic landscape review frames JOAG as frequently requiring surgical treatment due to extreme IOP elevation (>50 mmHg in some cases) and emphasizes MYOC-driven disease biology (ER accumulation → UPR/ER stress → TM cell loss). (pan2024exploringthegenetic pages 9-11)

13. Prevention

No primary prevention methods specific to JOAG were identified in the retrieved corpus. The most evidence-supported preventive strategy is secondary prevention via early detection in at-risk individuals (family screening) given the heritable nature and potential asymptomatic early course. (pan2024exploringthegenetic pages 1-2, souzeau2016anovelde pages 2-5)

14. Other species / natural disease

The retrieved corpus did not include naturally occurring JOAG in non-human species (OMIA/VetCompass) evidence.

15. Model organisms

A 2024 review summarizes MYOC model evidence supporting gain-of-function mechanisms and notes that MYOC knockout models do not reproduce glaucoma phenotypes, while expression of specific pathogenic human MYOC mutations (e.g., p.Y437H) in relevant ocular tissues can elevate IOP in mice under certain experimental strategies. (pan2024exploringthegenetic pages 9-11)

Visual evidence

Figure evidence supporting MYOC’s exon/domain organization and pathogenic-variant clustering is available from the 2024 review (Figure 5: MYOC gene structure and variants). (pan2024exploringthegenetic media 1a72f31d)

Summary tables

The following table consolidates high-yield disease facts, genetics, phenotypes, epidemiology, and treatment outcomes from the evidence base assembled here.

Domain	Key points	Quantitative data	Key sources
Clinical Definition & Onset	Primary open-angle glaucoma (POAG) subtype presenting in older children and young adults; features open angles and normal anterior segments without congenital anomalies (e.g., Haab's striae or increased corneal diameter).	Typical age of onset defined between 3 and 40 years, or sometimes specified as <35 years.	(almulhim2024agesexand pages 1-2, huang2018detectionofmutations pages 1-2, pan2024exploringthegenetic pages 9-11, almulhim2024agesexand pages 2-4)
Diagnostic Criteria	CGRN childhood glaucoma criteria require ≥2 findings: elevated IOP, glaucomatous optic nerve (ON) damage, corneal changes, or visual field (VF) defects. Cohort inclusions specify persistent IOP elevation and ON changes with open angles.	IOP ≥21 mmHg (CGRN) or >22 mmHg on 2+ occasions; C/D asymmetry ≥0.2.	(pan2024exploringthegenetic pages 1-2, almulhim2024agesexand pages 2-4)
Genetic Etiology	MYOC is the primary gene (autosomal dominant, variable penetrance); mutant proteins accumulate and misfold in the endoplasmic reticulum (ER) causing ER stress and trabecular meshwork cell death. CYP1B1, OPTN, FOXC1, and CPAMD8 variants are also implicated in JOAG/pediatric cohorts.	MYOC mutations explain 3.6%–9.5% (Saudi cohort) up to 36% of JOAG cases; >250 MYOC variants identified (37.7% pathogenic; 97% in exon 3, e.g., p.Gln368stop, p.Pro370Leu).	(OpenTargets Search: juvenile open angle glaucoma, huang2018detectionofmutations pages 1-2, pan2024exploringthegenetic pages 9-11, kumar2024geneticchangesand pages 1-2, almulhim2024agesexand pages 1-2)
Epidemiology	Rare globally, but comprises a notable fraction of childhood glaucoma cases. Incidence/prevalence varies significantly by region and referral population.	Estimated US incidence: 1 in 50,000; Accounts for ~0.7% of Caucasian glaucoma referrals and up to 15.5%–29.3% of childhood glaucoma cohorts.	(un2024surgicalapproachesto pages 1-2, diel2024resultsofa pages 23-26, mulugeta2024childhoodglaucomaprofile pages 1-3)
Clinical Phenotype	Patients often present with high myopia, significant family history, extremely high IOP, and rapid, severe visual field progression. Often asymptomatic until advanced.	Myopia prevalence ~93%; Family history ~51%; Preoperative mean IOP ~27–30 mmHg (can exceed 50 mmHg); Severe VF defects in 44%–57% of eyes; Mean C/D ratio 0.66–0.73.	(pan2024exploringthegenetic pages 9-11, almulhim2024agesexand pages 5-7, almulhim2024agesexand pages 2-4, almulhim2024agesexand pages 4-5, hu2025threeyearoutcomesof pages 1-2)
Treatment & Outcomes (2024-2025)	Highly refractory to medications; often requires surgery (e.g., GATT, trabeculectomy, deep sclerectomy). GATT is safe and effective, though complete success declines over a 3-year period.	Mean IOP reduction post-surgery: ~13–17 mmHg (down to ~14–17 mmHg final); Surgical control without reoperation: 76.9%–85.3%; GATT complete success: 73.7% at 1 yr, 51.7% at 3 yrs.	(un2024surgicalapproachesto pages 1-2, almulhim2024agesexand pages 4-5, hu2025threeyearoutcomesof pages 1-2, mulugeta2024childhoodglaucomaprofile pages 1-3)

Table: A summary table of recent (2024-2025) and core literature findings on Juvenile Open-Angle Glaucoma (JOAG), detailing diagnostic criteria, genetic etiology, clinical phenotypes, and surgical treatment outcomes.

Key recent developments (prioritized 2023–2024)

1) Systematic evidence synthesis (2024): Childhood glaucoma genetics review aggregates 196 studies and reports that MYOC variant prevalence can be up to 36% in JOAG and that CYP1B1, MYOC, and FOXC1 are among the most frequently studied genes across pediatric glaucoma. (kumar2024geneticchangesand pages 1-2, kumar2024geneticchangesand pages 2-5) 2) Updated mechanistic synthesis (2024): Review integrates MYOC proteostasis mechanism—ER retention and UPR/ER stress leading to TM cell loss and IOP elevation—and provides curated mutation statistics (e.g., >250 MYOC variants, ~97% of pathogenic variants in exon 3). (pan2024exploringthegenetic pages 9-11) 3) Precision variant interpretation (2023): MYOC variant pathogenicity can be differentiated using a biophysical metric (OLF thermal stability cutoff), enabling more actionable clinical genetics for rare variants. (scelsi2023quantitativedifferentiationof pages 1-3) 4) Contemporary real-world cohort characterization (2024): Tertiary-center cohort reports high myopia (93%), family history (51%), severe visual field defects, and large IOP reductions with both surgical and non-surgical management. (almulhim2024agesexand pages 4-5, almulhim2024agesexand pages 5-7)

Primary source URLs and publication dates (from retrieved corpus)

Pan Y, Iwata T. Exploring the Genetic Landscape of Childhood Glaucoma. Children. Published 2024-04-09. https://doi.org/10.3390/children11040454 (pan2024exploringthegenetic pages 1-2, pan2024exploringthegenetic pages 9-11)
Kumar A, Han Y, Oatts JT. Genetic changes and testing associated with childhood glaucoma: a systematic review. PLOS ONE. Published 2024-02. https://doi.org/10.1371/journal.pone.0298883 (kumar2024geneticchangesand pages 1-2)
Almulhim A, Almulhim A. Age, Sex, and Clinical Characteristics of JOAG Patients… Medicina. Published 2024-09. https://doi.org/10.3390/medicina60101591 (almulhim2024agesexand pages 5-7)
Huang C et al. Detection of mutations in MYOC, OPTN, … in Chinese JOAG using exome sequencing. Scientific Reports. Published 2018-03. https://doi.org/10.1038/s41598-018-22337-2 (huang2018detectionofmutations pages 1-2)
Souzeau E et al. A novel de novo MYOC variant in sporadic JOAG. BMC Medical Genetics. Published 2016-04. https://doi.org/10.1186/s12881-016-0291-5 (souzeau2016anovelde pages 2-5)
Scelsi HF et al. Quantitative differentiation of benign and misfolded glaucoma-causing MYOC variants… Disease Models & Mechanisms. Published 2023-01. https://doi.org/10.1242/dmm.049816 (scelsi2023quantitativedifferentiationof pages 1-3)

Limitations of this report (evidence availability)

OMIM/Orphanet/ICD/MeSH identifier fields and certain guideline-level treatment algorithms were not directly retrievable from the full texts accessed in this run.
JOAG-specific penetrance estimates, modifier genes, epigenetic signatures, and high-quality JOAG-specific QoL outcomes were not present in the retrieved evidence corpus.

References

(OpenTargets Search: juvenile open angle glaucoma): Open Targets Query (juvenile open angle glaucoma, 35 results). Buniello, A. et al. (2025). Open Targets Platform: facilitating therapeutic hypotheses building in drug discovery. Nucleic Acids Research.
(pan2024exploringthegenetic pages 1-2): Yang Pan and Takeshi Iwata. Exploring the genetic landscape of childhood glaucoma. Children, 11:454, Apr 2024. URL: https://doi.org/10.3390/children11040454, doi:10.3390/children11040454. This article has 15 citations.
(almulhim2024agesexand pages 1-2): Amar Almulhim and Abdulmohsen Almulhim. Age, sex, and clinical characteristics of juvenile open-angle glaucoma patients in a saudi tertiary hospital: a retrospective study of surgical and non-surgical outcomes. Medicina, 60:1591, Sep 2024. URL: https://doi.org/10.3390/medicina60101591, doi:10.3390/medicina60101591. This article has 3 citations.
(huang2018detectionofmutations pages 1-2): Chukai Huang, Lijing Xie, Zhenggen Wu, Yingjie Cao, Yuqian Zheng, Chi-Pui Pang, and Mingzhi Zhang. Detection of mutations in myoc, optn, ntf4, wdr36 and cyp1b1 in chinese juvenile onset open-angle glaucoma using exome sequencing. Scientific Reports, Mar 2018. URL: https://doi.org/10.1038/s41598-018-22337-2, doi:10.1038/s41598-018-22337-2. This article has 58 citations and is from a peer-reviewed journal.
(pan2024exploringthegenetic pages 9-11): Yang Pan and Takeshi Iwata. Exploring the genetic landscape of childhood glaucoma. Children, 11:454, Apr 2024. URL: https://doi.org/10.3390/children11040454, doi:10.3390/children11040454. This article has 15 citations.
(almulhim2024agesexand pages 2-4): Amar Almulhim and Abdulmohsen Almulhim. Age, sex, and clinical characteristics of juvenile open-angle glaucoma patients in a saudi tertiary hospital: a retrospective study of surgical and non-surgical outcomes. Medicina, 60:1591, Sep 2024. URL: https://doi.org/10.3390/medicina60101591, doi:10.3390/medicina60101591. This article has 3 citations.
(kumar2024geneticchangesand pages 1-2): Anika Kumar, Ying Han, and Julius T. Oatts. Genetic changes and testing associated with childhood glaucoma: a systematic review. PLOS ONE, 19:e0298883, Feb 2024. URL: https://doi.org/10.1371/journal.pone.0298883, doi:10.1371/journal.pone.0298883. This article has 20 citations and is from a peer-reviewed journal.
(almulhim2024agesexand pages 5-7): Amar Almulhim and Abdulmohsen Almulhim. Age, sex, and clinical characteristics of juvenile open-angle glaucoma patients in a saudi tertiary hospital: a retrospective study of surgical and non-surgical outcomes. Medicina, 60:1591, Sep 2024. URL: https://doi.org/10.3390/medicina60101591, doi:10.3390/medicina60101591. This article has 3 citations.
(un2024surgicalapproachesto pages 1-2): Y Un, S Imamoglu, O Alpogan, and R Bolac. Surgical approaches to juvenile open-angle glaucoma. European Eye Research, pages 42-50, Jan 2024. URL: https://doi.org/10.14744/eer.2023.39306, doi:10.14744/eer.2023.39306. This article has 4 citations.
(souzeau2016anovelde pages 2-5): Emmanuelle Souzeau, Kathryn P. Burdon, Bronwyn Ridge, Andrew Dubowsky, Jonathan B. Ruddle, and Jamie E. Craig. A novel de novo myocilin variant in a patient with sporadic juvenile open angle glaucoma. BMC Medical Genetics, Apr 2016. URL: https://doi.org/10.1186/s12881-016-0291-5, doi:10.1186/s12881-016-0291-5. This article has 15 citations and is from a peer-reviewed journal.
(scelsi2023quantitativedifferentiationof pages 1-3): Hailee F. Scelsi, Kamisha R. Hill, Brett M. Barlow, Mackenzie D. Martin, and Raquel L. Lieberman. Quantitative differentiation of benign and misfolded glaucoma-causing myocilin variants on the basis of protein thermal stability. Disease Models & Mechanisms, Jan 2023. URL: https://doi.org/10.1242/dmm.049816, doi:10.1242/dmm.049816. This article has 11 citations and is from a domain leading peer-reviewed journal.
(almulhim2024agesexand pages 4-5): Amar Almulhim and Abdulmohsen Almulhim. Age, sex, and clinical characteristics of juvenile open-angle glaucoma patients in a saudi tertiary hospital: a retrospective study of surgical and non-surgical outcomes. Medicina, 60:1591, Sep 2024. URL: https://doi.org/10.3390/medicina60101591, doi:10.3390/medicina60101591. This article has 3 citations.
(mulugeta2024childhoodglaucomaprofile pages 1-3): Tarekegn Mulugeta, Guteta Gebremichael, and Sufa Adugna. Childhood glaucoma profile in a southwestern ethiopia tertiary care center: a retrospective study. BMC Ophthalmology, Jan 2024. URL: https://doi.org/10.1186/s12886-023-03268-7, doi:10.1186/s12886-023-03268-7. This article has 2 citations and is from a peer-reviewed journal.
(diel2024resultsofa pages 23-26): Results of a pilot study at the Department of Ophthalmology at Mainz University Medical Center to establish a nationwide registry for childhood glaucoma in Germany This article has 0 citations and is from a peer-reviewed journal.
(hu2025threeyearoutcomesof pages 1-2): Baiyu Hu, Suju Liu, Hanying Fan, and Liuzhi Zeng. Three-year outcomes of gonioscopy-assisted transluminal trabeculotomy for juvenile-onset primary open-angle glaucoma: a retrospective study. BMC Ophthalmology, Apr 2025. URL: https://doi.org/10.1186/s12886-025-03930-2, doi:10.1186/s12886-025-03930-2. This article has 3 citations and is from a peer-reviewed journal.
(pan2024exploringthegenetic media 1a72f31d): Yang Pan and Takeshi Iwata. Exploring the genetic landscape of childhood glaucoma. Children, 11:454, Apr 2024. URL: https://doi.org/10.3390/children11040454, doi:10.3390/children11040454. This article has 15 citations.
(kumar2024geneticchangesand pages 2-5): Anika Kumar, Ying Han, and Julius T. Oatts. Genetic changes and testing associated with childhood glaucoma: a systematic review. PLOS ONE, 19:e0298883, Feb 2024. URL: https://doi.org/10.1371/journal.pone.0298883, doi:10.1371/journal.pone.0298883. This article has 20 citations and is from a peer-reviewed journal.

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Juvenile Open-Angle Glaucoma (JOAG) — Disease Characteristics Research Report

Executive overview (current understanding)

1. Disease information

1.1 Definition and overview

1.2 Key identifiers

1.3 Synonyms / alternative names

1.4 Evidence type

2. Etiology

2.1 Disease causal factors (primary causes)

2.2 Risk factors

2.3 Protective factors

2.4 Gene–environment interactions

3. Phenotypes

3.1 Core clinical phenotype (human)

3.2 Quality-of-life impact

4. Genetic / molecular information

4.1 Causal genes (and evidence)

4.2 Pathogenic variants (examples from primary literature)

4.3 Inheritance, penetrance, expressivity

4.4 Functional consequences and variant interpretation (recent development)

5. Environmental information

6. Mechanism / pathophysiology

6.1 Causal chain (MYOC-centered, current consensus)

6.2 Pathways, cell types, and ontology suggestions

7. Anatomical structures affected

8. Temporal development

9. Inheritance and population

9.1 Epidemiology (recently extracted quantitative data)

9.2 Inheritance pattern

9.3 Founder effects / population-specific variants

10. Diagnostics

10.1 Clinical diagnostic criteria and tests

10.2 Genetic testing (current state)

11. Outcome / prognosis

12. Treatment

12.1 Current applications and real-world implementations

12.2 MAXO terms (suggested)

12.3 Expert opinion / analysis (authoritative synthesis)

13. Prevention

14. Other species / natural disease

15. Model organisms

Visual evidence

Summary tables

Key recent developments (prioritized 2023–2024)

Primary source URLs and publication dates (from retrieved corpus)

Limitations of this report (evidence availability)

Artifacts