> Trialight public data. Index of pages: https://trialight.com/llms.txt
> Web page: https://trialight.com/data/condition/erythrocytosis-familial-4-b6fc07cf-50d1-5a33-942c-4ef87e7fcb15
> Record changed: 2026-10-13

# Erythrocytosis, familial, 4

Therapeutic area

Hematology

Rare disease

No

## Definition and classification

**Definition**

Any familial polycythemia in which the cause of the disease is a mutation in the EPAS1 gene.

**Genetic basis**

Yes

**Non-human condition**

No

**Rare disease**

No

**Listing at source**

Listed

**Condition name**

Erythrocytosis, familial, 4

**Therapeutic area**

Hematology

### Alternative names (6)

- erythrocytosis, familial, 4
- EPAS1 familial polycythemia
- erythrocytosis, familial, 4
- erythrocytosis, familial, type 4
- familial polycythemia caused by mutation in EPAS1
- ECYT4

## Clinical profile

**Severity**

Mild

### Disease mechanisms (2)

- Genetic
- Hereditary

### All therapeutic areas (3)

- Hematology
- Immunology
- Rheumatology

## Identifiers

**MONDO ID**

MONDO:0012729

Source: [monarchinitiative.org](https://monarchinitiative.org/MONDO:0012729)

**Parent condition**

MONDO:0001115

## Related records

### Broader conditions (13)

- Bone marrow disorder
- Disease
- Disease by body system or component
- Disease by etiologic mechanism
- Disease of genetic or genomic mechanism
- Familial polycythemia
- Hematologic disorder
- Hereditary disease
- Human disease
- [Immune system disorder](https://trialight.com/data/condition/immune-system-disorder-24846188-b462-515c-bb34-142255a648c8.md)
- Musculoskeletal system disorder
- Polycythemia
- Skeletal system disorder

### Trials (2)

- [A Phase 1 Study of AB521 Monotherapy and Combination Therapies in Renal Cell Carcinoma and Other Solid Tumors](https://trialight.com/data/trial/a-phase-1-study-of-ab521-monotherapy-and-combination-e1b2f8d0-943b-4fb4-a208-30e7ab9efff0.md)
- Assessment of Salivary Biomarker Levels in Individuals With Various Periodontal Diseases

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