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Treacher Collins syndrome 2

Synonyms
POLR1D-Related Treacher Collins Syndrome; TREACHER COLLINS SYNDROME 2, AUTOSOMAL RECESSIVE

Summary

Excerpted from the GeneReview: Treacher Collins Syndrome
Treacher Collins syndrome (TCS) is characterized by lower eyelid abnormalities, malar hypoplasia, downslanted palpebral fissures, and micro- or retrognathia due to symmetric hypoplasia of the zygomatic bones, maxilla, and mandible. External ear anomalies include absent, small, malformed, and/or posteriorly rotated ears and atresia or stenosis of the external auditory canals. About 40%-50% of individuals have conductive hearing loss attributed most commonly to malformation of the ossicles and hypoplasia of the middle ear cavities. Inner ear structures tend to be normal. Significant respiratory and feeding difficulties can be present in infancy. Other, less common abnormalities include cleft palate and unilateral or bilateral choanal stenosis or atresia. Typically, intellect is normal.
Full text of GeneReview (by section):
Summary
Diagnosis
Clinical Characteristics
Genetically Related (Allelic) Disorders
Differential Diagnosis
Management
Genetic Counseling
Resources
Molecular Genetics
Chapter Notes
References
Authors:
Mafalda Barbosa
Ethylin Wang Jabs
Sara Huston
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Available tests

45 tests are in the database for this condition.

Check Related conditions for additional relevant tests.

Clinical tests (45 available)

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: AC19, POLR1C, RPA16, RPA9, RPAC2, RPC16, RPO1-3, TCS2, POLR1D
    Summary: RNA polymerase I and III subunit D

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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