中文摘要：

目的分析mtDNA A1555G突变在库尔勒、滨州，成都和上海四个不同经济发展地区的携带情况。方法对4个地区332例耳聋者进行临床资料采集，外周静脉血抽取。血样经基因组DNA提取，进行线粒体DNA A1555G突变的酶切和直接测序检测，比较4个地区的携带率差异。结果332例耳聋者中共发现A1555G突变者11例，携带率为3．31％（11／332）。库尔勒、滨州、成都和上海四个地区mtDNA A1555G携带率分别为9．09％、6．67％、0和0。上海．成都合计与新疆汉族、滨州合计比较有统计学意义（P=0．000）。结论mtDNA A1555G突变在中国经济相对落后地区非综合征性耳聋患者中阳性率高于经济发达地区，中国不同地区间mtDNA A1555G突变检出率存在显著差异。

英文摘要：

Objective To investigate the prevalence of mitochondrial DNA （mtDNA） A1555G mutation in patients with nonsyndromic hearing impairment from Korla in Xinjiang, Binzhou in Shandong, Chengdu in Sichuan and Shanghai. Methods The medical histories of 332 hearing- impaired patients from four Chinese regions were collected and the blood samples obtained from these patients with informed consents. The mitochondrial DNA target fragments were amplified by polymerase chain reaction （PCR）. The mutations were detected by restriction-fragment-length polymorphism and sequence analysis. Results The detection rate of mtDNA A1555G mutation was 3.31% （11/332） among patients with sensorineural hearing loss. The carrier frequencies of mtDNA A1555G mutation in four regions were 9.09%, 6.67%, 0 and 0, respectively. There was significant difference in mtDNA A1555G mutation prevalence between the patients from Korla and Binzhou and those from Chengdu and Shanghai （Fisher＇s exact,P=0.000）. Conclusion The results showed that the prevalence of mtDNA A1555G was higher in less-developed regions than that in the developed. There were significant differences in the detection rate of mtDNA A1555G between different regions of China.