microtia
Findings
No curated finding names microtia yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A congenital malformation of the external ear, seen more frequently in males, that occurs sporadically or is inherited, that is characterized by unilateral (79-93% of cases, 60% of which involve the right ear) or bilateral small and abnormally shaped auricles and that is often associated with atresia or stenosis of the ear canal, attention deficit disorders and delayed language development. The variation in auricle size ranges from grade I, where the auricle is simply smaller than normal, to grade IV, also known as anotia, where there is a complete absence of the external ear and of the auditory canal.
Definition from the Mondo Disease Ontology (MONDO:0010920), read 2026-09-29. CC BY 4.0.
Features
9 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.
- MicrotiaHPOHP:0008551
- Obligate (100% of cases)
- Unilateral conductive hearing impairmentHPOHP:0040119
- Very frequent (80% to 99% of cases)
- Abnormal pinna morphologyHPOHP:0000377
- Frequent (30% to 79% of cases)
- AnotiaHPOHP:0009892
- Frequent (30% to 79% of cases)
- Atresia of the external auditory canalHPOHP:0000413
- Frequent (30% to 79% of cases)
- Delayed speech and language developmentHPOHP:0000750
- Frequent (30% to 79% of cases)
- Hypoplastic helices
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.
- HOXA2HGNC:5103
- Supportive · Orphanet · Autosomal dominant · 2021
Where it sits
- Narrower terms (1)
Other names
5 names
Resolves to: microtia
- Also called
- congenital microtiasM-Amicrotia-anotiamicrotia, congenitalmicrotias, congenital