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Familial microtia in four generations with variable expressivity and incomplete penetrance in association with type I

S Balci1, K Boduroğlu, S Kaya

  • 1Department of Pediatrics, Hacettepe University Faculty of Medicine, Ankara, Turkey.

The Turkish Journal of Pediatrics
|January 5, 2002
PubMed

Insights

This study reports a rare familial case of microtia, ear canal atresia, and conductive deafness. Autosomal dominant inheritance with variable expressivity was observed across four generations.

Area of Science:

  • Genetics
  • Otolaryngology
  • Medical Genetics

Background:

  • Familial microtia with external ear canal atresia and conductive deafness is a rare condition.
  • Previous reports suggest both autosomal dominant and recessive inheritance patterns.
  • Microtia is often an isolated finding, but can be associated with other malformations.

Observation:

  • A family spanning four generations exhibited microtia, external auditory canal atresia, and conductive deafness.
  • The index case presented with an association of microtia and type I syndactyly.
  • Pedigree analysis revealed variable expressivity, incomplete penetrance, and generation skipping.

Findings:

  • The mode of inheritance in this family was determined to be autosomal dominant.
  • The co-occurrence of microtia with type I syndactyly is a novel observation.
  • Genetic factors influencing the expression and inheritance of these traits are highlighted.

Implications:

  • This case expands the understanding of the genetic basis of microtia and related ear malformations.
  • The findings emphasize the importance of detailed family history and genetic counseling in managing such conditions.
  • Further research into the specific genes and mechanisms involved in this familial syndrome is warranted.

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