Pan Jing, Xu Ping, Tang Weibo, Cui Zhongtao, Feng Miao, Wang Chunying
Department of Laboratory, The Fourth Affiliated Hospital of Harbin Medical University, 37 Yiyuan Street, Harbin, 150001, Heilongjiang province, China.
Department of Otolaryngology Head and Neck Surgery, The Fourth Affiliated Hospital of Harbin Medical University, 37 Yiyuan Street, Harbin, 150001, Heilongjiang province, China.
Int J Pediatr Otorhinolaryngol. 2017 Jul;98:39-42. doi: 10.1016/j.ijporl.2017.04.018. Epub 2017 Apr 12.
The molecular etiology of nonsyndromic deafness in Chinese population has not been investigated systematically, our study is aim to investigate the molecular etiology of nonsyndromic deafness patients from Northern China (Heilongjiang province), in order to provide genetic test and counseling to families.
380 unrelated patients with hearing loss who attended to the Department of Otolaryngology, The Fourth Affiliated Hospital of Harbin Medical University were enrolled to our study. All patients were diagnosed with nonsyndromic deafness by audiologic evaluation, 202 normal-hearing individuals were taken as controls. Mutations in three common deafness-causing genes (GJB2, SLC26A4 and 12S rRNA) were screened by direct sequencing.
Mutations (homozygote or compound heterozygote) in GJB2 accounted for 8.9% (34/380) of the patients, mutations in SLC26A4 accounted for 10.0% (38/380) of the patients screened. Only one case was found to carry 12S rRNA 1555A > G (1/380, 0.26%). Five types of mutations in GJB2 were identified, GJB2 235delC was the most prevalent mutation in our patient group (76/380, 20.0%), followed by 299-300delAT with a frequency of 7.4% (28/380). Two types of mutations in SLC26A4 were detected in our patient group (IVS7-2A > G and 2168A > G). IVS7-2A > G was identified in 27 patients (27/380, 7.1%) and 2168A > G was identified in 14 patients (14/380, 3.7%).
Our results demonstrate that 19.2% patients with nonsyndromic deafness were caused by mutations in three common deafness genes (GJB2, SLC26A4 and 12S rRNA) in our northern China patient group. GJB2 235delC was the most prevalent mutation, same as in the most Asian populations. These data enrich the database of deafness mutations and provide the standard for clinical diagnose, treatment and genetic counseling in Northern China population.
中国人群非综合征性耳聋的分子病因尚未得到系统研究，本研究旨在调查中国北方（黑龙江省）非综合征性耳聋患者的分子病因，以便为家庭提供基因检测和咨询服务。
选取哈尔滨医科大学附属第四医院耳鼻咽喉科就诊的380例无血缘关系的听力损失患者纳入研究。所有患者均通过听力学评估诊断为非综合征性耳聋，选取202例听力正常个体作为对照。采用直接测序法筛查三个常见致聋基因（GJB2、SLC26A4和12S rRNA）的突变情况。
GJB2基因的突变（纯合子或复合杂合子）占患者的8.9%（34/380），SLC26A4基因的突变占筛查患者的10.0%（38/380）。仅发现1例携带12S rRNA 1555A>G突变（1/380，0.26%）。共鉴定出GJB2基因的五种突变类型，其中GJB2 235delC是本患者组中最常见的突变（76/380，20.0%），其次是299-300delAT，频率为7.4%（28/380）。在本患者组中检测到SLC26A4基因的两种突变类型（IVS7-2A>G和2168A>G）。IVS7-2A>G在27例患者中被鉴定出（27/380，7.1%），2168A>G在14例患者中被鉴定出（14/380，3.7%）。
我们的研究结果表明，在中国北方患者组中，19.2%的非综合征性耳聋患者是由三个常见致聋基因（GJB2、SLC26A4和12S rRNA）的突变引起的。GJB2 235delC是最常见的突变，与大多数亚洲人群相同。这些数据丰富了耳聋突变数据库，为中国北方人群的临床诊断、治疗和遗传咨询提供了标准。
