metaphyseal chondrodysplasia, Jansen type
Findings
No curated finding names metaphyseal chondrodysplasia, Jansen type yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Jansen's metaphyseal chondrodysplasia (JMC) is a very rare autosomal dominant skeletal dysplasia characterized by short-limbed short stature (due to severe metaphyseal changes that are often discovered in childhood by imaging), waddling gait, bowed legs, contracture deformities of the joints, short hands with clubbed fingers, clinodactyly, prominent upper face and small mandible, as well as chronic parathyroid hormone-independent hypercalcemia, hypercalciuria, and mild hypophosphatemia.
Definition from the Mondo Disease Ontology (MONDO:0007982), read 2026-09-29. CC BY 4.0.
Features
40 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.
- Delayed eruption of teethHPOHP:0000684
- 3 of 3 reported patients
- Downslanted palpebral fissuresHPOHP:0000494
- 6 of 6 reported patients
- Occasional (5% to 29% of cases)
- Flat palateHPOHP:6001411
- 6 of 6 reported patients
- HypertelorismHPOHP:0000316
- 6 of 6 reported patients
- Frequent (30% to 79% of cases)
- Low-set earsHPOHP:0000369
- 6 of 6 reported patients
- PtosisHPOHP:0000508
- 6 of 6 reported patients
Show the remaining 28
- Bowing of the long bonesHPOHP:0006487
- Frequent (30% to 79% of cases)
- Conductive hearing impairmentHPOHP:0000405
- 3 of 5 reported patients
- Dental malocclusionHPOHP:0000689
- 3 of 5 reported patients
- Disproportionate short-limb short statureHPO · MondoHP:0008873
- Frequent (30% to 79% of cases)
- Elevated circulating alkaline phosphatase concentrationHPOHP:0003155
- Frequent (30% to 79% of cases)
- High palateHPOHP:0000218
- Frequent (30% to 79% of cases)
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.
- PTH1RHGNC:9608
- Definitive · G2P · Autosomal dominant · 2023
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal dominant · 2023
- Strong · PanelApp Australia · Autosomal dominant · 2025
- Supportive · Orphanet · Autosomal dominant · 2021
Where it sits
Other names
4 names
Resolves to: metaphyseal chondrodysplasia, Jansen type
- Also called
- Jansen Type Metaphyseal Chondrodysplasiametaphyseal chondrodysplasia murk Jansen typemetaphyseal chondrodysplasia, murk Jansen typemurk Jansen type metaphyseal chondrodysplasia