thrombocytopenia-absent radius syndrome
Findings
No curated finding names thrombocytopenia-absent radius syndrome yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Thrombocytopenia-absent radius (TAR) syndrome is a very rare congenital malformation syndrome characterized by bilateral radial aplasia and thrombocytopenia.
Definition from the Mondo Disease Ontology (MONDO:0010121), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal recessive inheritance
- Onset and course
- Congenital onset
HPO, annotations 2026-09-02
Features
81 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.
- Adducted thumbHPOHP:0001181
- 1 of 1 reported patient
- Occasional (5% to 29% of cases)
- AnemiaHPOHP:0001903
- 1 of 1 reported patient · Infantile onset
- Bilateral radial aplasiaHPOHP:0004977
- 67 of 67 reported patients
- CataractHPOHP:0000518
- 1 of 1 reported patient
- Cerebellar vermis hypoplasiaHPOHP:0001320
- 1 of 1 reported patient
- Coarctation of aortaHPOHP:0001680
- 1 of 1 reported patient
- Corneal opacity
Show the remaining 69
- Ulnar deviation of the handHPOHP:0009487
- 1 of 1 reported patient
- Vesicoureteral refluxHPOHP:0000076
- 1 of 1 reported patient
- Short thumbHPOHP:0009778
- 25 of 26 reported patients
- ThrombocytopeniaHPOHP:0001873
- 78 of 82 reported patients
- Very frequent (80% to 99% of cases)
- Absent radiusHPOHP:0003974
- 21 of 26 reported patients
- Very frequent (80% to 99% of cases)
- Abnormality of coagulationHPOHP:0001928
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.
- RBM8AHGNC:9905
- Definitive · ClinGen · Autosomal recessive · 2020
- Definitive · Laboratory for Molecular Medicine · Autosomal recessive · 2020
- Definitive · G2P · Autosomal recessive · 2023
- Strong · Ambry Genetics · Autosomal recessive · 2021
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2021
- Strong · PanelApp Australia · Autosomal recessive · 2025
- Supportive · Orphanet · Autosomal recessive · 2021
Where it sits
Other names
4 names
Resolves to: thrombocytopenia-absent radius syndrome
- Also called
- 1q21.1 susceptibility locus for Thrombocytopenia-Absent Radius (TAR) syndromeradial aplasia-thrombocytopenia syndromeTAR syndromeThrombocytopenia Absent Radius Syndrome