非综合征型聋患儿 SLC26A4基因突变分析

摘要

Objective To study the SLC26A4 mutations in children with non -syndromic hearing loss by ge-netic testing method ,for the purpose of investigating etiology and mutation regularity of hearing loss ,and to provide basic information for the molecular diagnosis of hearing loss .Methods Blood samples and clinical data of 137 spo-radic cases with non -syndromic hearing loss and 126 normal controls were collected .The SLC26A4 gene of the pa-tients and normal controls were amplified by polymerase chain reaction (PCR) ,then subjected to automatic DNA se-quencing .Results Pathologic SLC26A4 mutations were identified in 23 out of 137 patients ,and in 23 out of 119 bi-lateral deafness ,mutate rate were 16 .79% and 19 .33% ,respectively .SLC26A4 mutations were identified in 19 out of 20(95% ) patients with bilateral LVA .A total of 11 mutations were identified in the present study ,including 4 novel mutations (E29K(c .85G>A) ,R79X(c .235C> T) ,C282G(c .844T>G) ,V285I(c .853G>A) )and 7 repor-ted mutations .In the present study ,IVS7-2A>G was the most common mutation ,and was detected in 19 out of 23(82 .61% ) patients with SLC26A4 mutations .Conclusion SLC26A4 mutations ,the common reason for non -syndromic hearing loss ,were closely related with LVA .IVS7-2A>G was the most common mutation in SLC26A4 mutant .%目的应用基因检测技术分析非综合征型聋患儿SLC26A4基因突变情况，探讨其病因及突变规律。方法收集137例6个月～13岁散发非综合征型聋患儿（耳聋组，双侧聋119例，单侧聋18例）和126例正常对照者（对照组）的外周血样本和临床资料，应用聚合酶链反应（PCR）和直接测序法对耳聋组和对照组进行SLC26A4基因突变检测。结果耳聋组中23例发现SLC26A4基因突变，占16．79％（23/137），占双侧耳聋患者的19．33％（23/119）；20例双侧前庭水管扩大（LVA）的患者中SLC26A4基因突变19例，占95．0％（19/20）。共发现11种突变，包括4种国际上尚未报道的突变：E29K（c ．85G＞ A）、R79X（c ．235C＞ T）、C282G（c ．844T＞ G）和 V285I（c ．853G＞A），7种已报道突变，其中IVS7-2A＞G是最常见的突变，23例SLC26A4基因突变患者中有19例有IVS7-2A＞G突变，约占82．61％（19/23）。对照组中未检出SLC26A4基因致病突变。结论 SLC26A4基因突变与LVA密切相关，是非综合征型聋的常见病因，其中IVS7-2A＞G突变最常见。