Pedigree and genetic study of a bilateral congenital microtia family

Microtia can be defined as a malformation of the auricle; the varying severity that results can range from mild distortion of the anatomic landmarks to the complete absence of the ear. No specific study has been reported analyzing a family of several generations with bilateral congenital concha-type microtia so far.

The authors obtained medical records and blood samples from a Chinese family with bilateral congenital concha-type microtia that involved 56 members of five generations. There were 20 patients with bilateral congenital concha-type microtia in this pedigree, and 14 patients were still alive. Pedigree analysis and genetic study were carried out to obtain the information in this family.

With regard to pedigree, 35.7 percent of the members of this family were affected by bilateral congenital concha-type microtia and showed the possibility of autosomal dominant inheritance model. Missense mutation A deletion on site 76234730 in goosecoid gene exon 3 occurred in eight cases in the family, which resulted in a frame shift mutation.

The goosecoid gene mutation in exon 3 may be involved in the malformation events in this family. The mutation can be accompanied by potential environmental risk factors, such as exposure to poison and hazardous materials, alcohol abuse, and disease during the mother's pregnancy. Further study is needed to clarify the relationship between the genetic and environmental factors associated with the congenital malformation.