FGFR3

fibroblast growth factor receptor 3

13 disorders 8 untyped 3 causative 1 unknown 1 susceptibility 4p16.3 gene with protein product

HGNC:3690 Monarch NCBI Gene 2261 ENSG00000068078 UniProt P22607 OMIM 134934

Previous symbols: ACH. Aliases: CEK2, JTK4, CD333.

In the knowledge base · computed from kb/ at build time

Disorders

Relationship is the entry's genetic[].relationship_type. untyped means the entry has a genetic record for the gene but does not type it; its free-text association is shown instead.

Disorder	Relationship	Where the gene appears
Achondroplasia	causative germline CLINGEN: definitive	mechanism: FGFR3 p.Gly380Arg gain-of-function with impaired receptor down-regulation
CATSHL Syndrome	unknown germline CLINGEN: moderate	mechanism: FGFR3 Coding Missense Variation; FGFR3 Kinase-Domain Loss of Function
Crouzon Syndrome with Acanthosis Nigricans	causative	mechanism: FGFR3 A391E Transmembrane Dimer Stabilization
Thanatophoric Dysplasia	causative de novo CLINGEN: definitive	mechanism: Graded FGFR3 Gain-of-Function Activation subtype: TD1; TD2
Wolf-Hirschhorn_Syndrome	susceptibility	mechanism: Candidate FGFR3-Dependent Neural-Crest Signaling Defect
Bladder Urothelial Carcinoma	untyped Somatic Activating Mutation or Fusion
FGFR-Altered Urothelial Carcinoma	untyped Somatic Activating Mutations and Fusions
Hypochondroplasia	untyped Causative; Pathogenic Variants	mechanism: FGFR3 constitutive activation animal model: Mouse
Muenke Syndrome	untyped Causative; Pathogenic Variants
SADDAN	untyped Causative	mechanism: Constitutive FGFR3 kinase activity; FGFR3 p.Lys650Met mutation
Thanatophoric Dysplasia Type 1	untyped Causative	mechanism: FGFR3 constitutive activation via cysteine mutations animal model: Mouse
Thanatophoric Dysplasia Type 2	untyped Causative	mechanism: Constitutive FGFR3 kinase activation by K650E animal model: Mouse (Mus musculus)
Transitional Cell Carcinoma	untyped somatic

ClinGen gene–disease validity · snapshot 2026-10-03 · matched to entries by MONDO

An entry matches when ClinGen's MONDO disease is the entry's own disease term, a subtype term, or an exact-match mapping. An amber status marks an entry ClinGen supports the gene for (Definitive, Strong or Moderate) whose own record does not type it. A Limited, Disputed or Refuted tier on such an entry is not a gap.

ClinGen disease	MOI	Classification	dismech entry
achondroplasia MONDO:0007037	AD	Definitive 2023-09-28	Achondroplasia causative
hypochondroplasia MONDO:0007793	AD	Definitive 2023-09-28	Hypochondroplasia untyped
Muenke syndrome MONDO:0011274	AD	Definitive 2022-03-29	Muenke Syndrome untyped
camptodactyly-tall stature-scoliosis-hearing loss syndrome MONDO:0012504	SD	Moderate 2026-08-24	CATSHL Syndrome unknown
Crouzon syndrome-acanthosis nigricans syndrome MONDO:0012833	AD	Definitive 2021-11-18	Crouzon Syndrome with Acanthosis Nigricans causative
severe achondroplasia-developmental delay-acanthosis nigricans syndrome MONDO:0014658	AD	Moderate 2022-05-09	SADDAN untyped
thanatophoric dysplasia MONDO:0017042	AD	Definitive 2022-01-13	Thanatophoric Dysplasia causative

Mechanism modules · computed from kb/

fgfr_gain_of_function_skeletal_dysplasia via Achondroplasia, Crouzon Syndrome with Acanthosis Nigricans, Hypochondroplasia, SADDAN, Thanatophoric Dysplasia, Thanatophoric Dysplasia Type 1, Thanatophoric Dysplasia Type 2 named in the module itself

Identity from HGNC (snapshot 2026-10-01). Page layers are described in the gene pages documentation.