Haghighat-Nia Asieh, Keivani Azadeh, Nadeali Zakiye, Fazel-Najafabadi Esmat, Hosseinzadeh Majid, Salehi Mansoor
Medical Genetics Laboratory, Alzahra University Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.
Medical Genetics Laboratory, Alzahra University Hospital, Isfahan University of Medical Sciences, Isfahan, Iran; Department of Medical Genetics, School of Medicine, Tehran University of Medical Science, Tehran, Iran.
Int J Pediatr Otorhinolaryngol. 2015 Nov;79(11):1892-5. doi: 10.1016/j.ijporl.2015.08.039. Epub 2015 Sep 2.
To identify the spectrum of mutations in connexin 26 gene and frequency of two deletions in connexin 30 gene in central Iran.
After extraction of DNA from 300 blood samples, connexin 26 gene coding region was amplified using specific primers. PCR products were used for bidirectional sequencing. Multiplex PCR was used for detection of del(GJB6-D13S1830) and del(GJB6-D13S1854) in the GJB6 gene.
Eighteen different mutations including two novel variants in GJB2 gene were detected. The GJB2 mutations were observed in 23.3% of all the subjects. In addition, none of the deaf patients carried the del(GJB6-D13S1830) and del(GJB6-D13S1854) in the GJB6 gene. The 35delG mutation was the most common mutation, accounting for 32.65% of the mutant alleles.
The present study indicates that mutations in the GJB2 gene particularly 35delG are important causes for ARNSHL. 60% of the patients were heterozygous carriers. Thus, further investigation is needed to detect the genetic cause of hearing loss in patients with mono allelic mutations in the coding region of GJB2.
确定伊朗中部连接蛋白26基因的突变谱以及连接蛋白30基因中两种缺失的频率。
从300份血液样本中提取DNA后，使用特异性引物扩增连接蛋白26基因编码区。PCR产物用于双向测序。多重PCR用于检测GJB6基因中的del(GJB6-D13S1830)和del(GJB6-D13S1854)。
检测到18种不同的突变，包括GJB2基因中的两种新变异。在所有受试者中，23.3%观察到GJB2突变。此外，耳聋患者中均未携带GJB6基因中的del(GJB6-D13S1830)和del(GJB6-D13S1854)。35delG突变是最常见的突变，占突变等位基因的32.65%。
本研究表明，GJB2基因中的突变尤其是35delG是常染色体隐性非综合征性听力损失的重要原因。60%的患者为杂合子携带者。因此，需要进一步研究以检测GJB2编码区单等位基因突变患者听力损失的遗传原因。
