A case report of diagnosis of a hearing loss gene carrier

Abstract

We report a case in which we diagnosed a carrier of a hearing loss gene. A 35-year-old man with hearing loss presented to us seeking to undergo genetic analysis for his sensory hearing loss. There were no persons among his family members or relatives, besides him, who suffered from hearing loss, except for his father who had mild bilateral hearing loss. The genetic analysis revealed that the patient was heterozygous for the G45E/Y136X mutation in the GJB2 gene. Then, his wife visited our hospital seeking carrier-state diagnosis of the hearing loss gene. Her hearing was normal. She wanted to understand the probability of hearing loss in her still unborn children. Although her pure-tone audiogram was almost normal, heterozygous 176-191del 16bp mutation of the GJB2 gene was detected. The rate of recurrence of hearing loss in their yet-to-be-born children was estimated to be 25-50%. It is necessary to perform carrier diagnosis according to the guideline on genetic testing and diagnosis, in cooperation with medical specialists in clinical hereditary disorders.