Angeli S, Utrera R, Dib S, Chiossone E, Naranjo C, Henríquez O, Porta M
Department of Otorhinolaryngology, Hospital San Juan de Dios, Caracas, Venezuela.
Acta Otolaryngol. 2000 Mar;120(2):133-6. doi: 10.1080/000164800750000766.
The frequency of childhood deafness is estimated at 1:1,000 and at least half of these cases are genetic. Recently, mutations in the GJB2 gene have been found in a great number of familial and sporadic cases of congenital deafness in Caucasians. The most common mutation (70%) is the frameshift mutation of a single guanine in position 35 (35delG). More than 20 mutations in the GJB2 gene are associated with DFNB1, a prevalent type of autosomal recessive non-syndromic neurosensory deafness. Last year we initiated a systematic screening programme to evaluate the causes of deafness in the population of prelingually deaf children who are referred to our cochlear implant programme. All of the deaf children and their parents undergo a comprehensive medical review, directed to identify causes of acquired deafness and manifestations of syndromic hearing impairment. DNA is extracted from the blood of all of the children. The technique AS-PCR (allele-specific polymerase chain reaction) is used for the identification of the mutation 35delG. Screening for other GJB2 gene mutations is carried out by single-strand conformation polymorphisms (SSCP). Our results on the identification of DFNB1 will be presented, as well as a discussion on the implications of an aetiological diagnosis in cochlear implantation.
儿童期耳聋的发生率估计为1:1000，其中至少一半病例是遗传性的。最近，在高加索人群中大量先天性耳聋的家族性和散发性病例中发现了GJB2基因突变。最常见的突变（70%）是第35位单个鸟嘌呤的移码突变（35delG）。GJB2基因中20多种突变与DFNB1相关，DFNB1是常染色体隐性非综合征性神经感觉性耳聋的一种常见类型。去年，我们启动了一项系统筛查计划，以评估转诊至我们人工耳蜗植入计划的语前聋儿童群体中耳聋的病因。所有耳聋儿童及其父母都接受了全面的医学检查，旨在确定后天性耳聋的病因和综合征性听力障碍的表现。从所有儿童的血液中提取DNA。采用等位基因特异性聚合酶链反应（AS-PCR）技术鉴定35delG突变。通过单链构象多态性（SSCP）对其他GJB2基因突变进行筛查。我们将展示关于DFNB1鉴定的结果，以及关于病因诊断在人工耳蜗植入中的意义的讨论。
