Genetic analysis in a Chinese family with autosomal dominant nonsyndromic deafness / 解放军医学杂志

ABSTRACT

Objective To analyze and determine the genetic characteristics of a large Chinese family with autosomal dominant nonsyndromic deafness(named pedigree Z029).Methods A hereditary deafness family was found from the profuse genetic resource established in the Otolaryngology Institute of PLA General Hospital.A sequence of bilateral sensorineural hearing impairment transmitted through five generations was found by investigating 47 individuals in the pedigree.The genetic forms of hearing loss in 18 members of the Z029 pedigree were diagnosed by otologic,audiologic,and physical examination,as well as by the study on their family history.Pedigree map was drawn by using Cyrillic2.1 software.Results The phynotype of Z029 family showed that most affected individuals had sensorineural hearing impairment with subsequent gradual progression covering all frequencies.The phynotype was transmitted from 1 to 5 generations.One of the parents of every patient was definitely a patient of the same disease.The affected ratio was same in both sexes,and the incidence of deafness declined through the first to fifth generation.Conclusion The phenotype characteristics of Z029 family were of autosomal dominant nonsyndromic hereditary deafness.In this pedigree,hearing impairment occurred in the majority of affected individuals after their twentieth year of age,and the penetrance of the impairment appeared to be age-correlated.No obvious vestibular dysfunction and other associated abnormalities were found.It may provide a foundation for the study of gene mapping and gene cloning of the pathogenic gene to analyze and determine the phenotype characteristics of this pedigree.This pedigree also provided an excellent model for the further study on the pathological and molecular mechanisms of hereditary hearing impairment related to age.