广州市188例聋校学生耳聋相关基因筛查结果分析

The Deafness-related Gene Detection Results of 188 Hearing-impaired Students in Guangzhou

目的探讨基因芯片及酶切法在非综合征性耳聋患者检测中的意义，初步了解广州地区耳聋患者的相关基因突变。方法选取广州市聋校学生188人作为研究对象，采用遗传性耳聋基因芯片进行4个常见基因（GJB2、GJB3、SLC26A4和线粒体DNA12SrRNA）9个致聋突变位点的检测，并用聚合酶链反应一限制性片段长度多态性（polymerasechainreaction-restrictionfragmentlengthpolymorphism，PCR-RFLP）对线粒体DNAA1555G突变、GJB2基因的235delC突变：〉DSLC26A4基因的IVS7-2A〉G突变位点进行检测。结果188例耳聋患者中检出42人携带耳聋相关基因突变，检出阳性率为22．34％，其中GJB2的235delc纯合突变12例，杂合突变3例，299—300delAT杂合突变l例，总检出率为8．51％；SLC26A4基因的IVS7-2A〉G纯合突变7例，IVS7-2A〉G、2168A〉G复合杂合突变1例，IVS7-2A〉G杂合突变17例，2168A〉G杂合突变2例，总检出率为13．83％。基因芯片的检测结果均与酶切法检测结果一致。结论基因芯片与传统的酶切法相比具有操作简单快速、高通量、高准确性、低成本等特点，易于对人群进行大规模且快速准确的筛查。

Objective To explore the significance of gene chips and restriction fragment length polymorphism（RFLP） in testing the patients with non-syndromic deafness and to investigate the common deaf-related gene mutations in Guangzhou. Methods The gene chip and RCR-RFLP were used to test 4 common deaf-related genes in 188 hearing-impaired students at schools for the deaf, including GJB2, GJB3, SLC26A4 and mitochondrial DNA t2S rRNA. Results 42 individuals carrying deafness-related gene mutations were detected in 188 cases and the positive rate was 22.34%. The 235delC homozygous mutation of GJB2 was found in 12 cases.The 235delC heterozygous mutation of GJB2 was found in 3 cases.The 299_300delAT beterozygous mutation of GJB2 was found in one case. The positive rate of GJB2 mutations was 8.51%. SLC26A4 gene IVS7-2A〉G homozygous mutation was found in 7 cases. IVS7-2A〉G/2168A〉G compound heterozygous mutation was found in one case while 17 cases were heterozygous of IVS7-2A〉G and 2 cases were heterozygous of 2168A〉G. The positive rate of SLC26A4 mutations was 13.83%. The gene chip test results were consistent with the results of enzyme assay. Conclusion The gene chips have advantages over RCR-RFLP because of its rapidness, high-throughput, high accuracy, low cost, simple operation and applicable for large-scale detection of deafness-related gene mutations.