Definition:

Congenital aural atresia (CAA) is an autosomal dominant defect that is characterized by hypoplasia of the external auditory canal, often in association with dysmorphic features of auricle, middle ear, and, occasionally, the inner ear structures. Recently, heterozygous mutations in TSHZ1 was described to cause CAA in human. TSHZ1 has been shown to be important for murine middle-ear development.