目的:研究GJB6基因[连接蛋白30(Cx30)-]在中国非综合征遗传性聋人群中的突变情况。方法:用特定引物对372例非综合征遗传性聋患者(其中295例分子病因不明,77例携带GJB2病理性单等位基因突变)和182例正常对照者进行聚合酶链反应,检测GJB6基因的342kb大片段缺失del(GJB6〉D13S1830),并进行GJB6基因编码区扩增,以产物直接测序方法进行突变检测及鉴定。结果:372例耳聋患者中未发现GJB6 del(GJB6〉D13S1830),其中1例发现携带GJB6基因点突变404C〉A,导致了氨基酸的错义改变T135K,多物种Cx30氨基酸序列进化分析证实该点位于Cx30高度保守的第3跨膜区。对照组中未发现同样突变。结论:GJB6基因突变在中国耳聋人群中整体发生频率较低,GJB6基因可暂不列为第一线耳聋基因检测项目。
Objective:To investigate the contribution of GJB6 gene (encoding connexin 30) mutation in Chinese population with sporadic non-syndromic hearing impairment. Method: Three hundred and seventy-two nonsyndromic hearing impairment patients and 182 normal controls were first tested for GJB6 del(GJB6〉D13S1830) using specific PCR primers. Then PCR was performed with a pair of primer flanking the whole coding sequence of GJB6 gene. Sequencing of GJB6 whole coding sequence PCR products was subsequently applied in all subjects with hearing loss and normal controls. Result: None of the patients and normal controls carried GJB6 del ( GJB6 〉D13S1830). Two single base pair changes were detected , one in the patient group and the other in the control group. The mutation found in the patient group was not detected in the control subjects. Conclusion: Mutation of GJB6 gene is not frequent in Chinese non-syndromic hearing-loss population. Screening for GJB6 gene can be ranked as unconventional deaf gene test in China temporarily.