syndactyly type 8
Findings
No curated finding names syndactyly type 8 yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Syndactyly type 8 is a rare, genetic, non-syndromic, congenital limb malformation characterized by unilateral or bilateral fusion of the fourth and fifth metacarpals with no other associated abnomalities. Patients present shortened fourth and fifth metacarpals with excessive separation between their distal ends, resulting in marked ulnar deviation of the little finger and an inability to bring the fifth finger in parallel with the other fingers.
Definition from the Mondo Disease Ontology (MONDO:0010669), read 2026-09-29. CC BY 4.0.
- Inheritance
- X-linked recessive inheritance
- Onset and course
- Congenital onset
HPO, annotations 2026-09-02
Features
4 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- 4-5 metacarpal synostosisHPOHP:0005867
- 2 of 2 reported patients
- Short 5th metacarpalHPOHP:0010047
- 2 of 2 reported patients
- 2-3 toe cutaneous syndactylyHPOHP:0005709
- 1 of 2 reported patients
- Clinodactyly of the 5th fingerHPOHP:0004209
- 1 of 2 reported patients
Genes
1 gene
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- FGF16HGNC:3672
- Strong · Labcorp Genetics (formerly Invitae) · X-linked · 2021
- Strong · PanelApp Australia · X-linked · 2025
- Supportive · Orphanet · Autosomal dominant · 2021
Where it sits
- A kind of
Other names
4 names
Resolves to: syndactyly type 8
- Also called
- FGF16 non-syndromic syndactylyfusion of metacarpals 4 and 5metacarpal 4-5 fusion, X-linked recessivenon-syndromic syndactyly caused by mutation in FGF16