近亲结婚所致一遗传性非综合征型耳聋家系的调查

耳聋是一种最常见的人类感觉系统缺陷，在已发现的遗传性耳聋中，有70％属于非综合征型听力缺损。据估计非综合征型遗传性耳聋基因总数在100个以上，目前已经确定了近80个非综合征型遗传性耳聋的遗传位点，其中23个基因已经被成功克隆。本报道一遗传性非综合征型耳聋家系。该家系中存在2代近亲结婚，共2代13人出现聋哑症状。经遗传分析，该家系的遗传方式与常染色体显性或隐性遗传均不符合，提示此家系中的非综合征型遗传性耳聋可能为线粒体突变所致。     

重视遗传性耳聋的基因诊断

聋是最常见的感觉障碍性疾病,是交流障碍最常见的病因。据世界卫生组织2002年估计,全球至少有二亿五千万人罹患中度以上听力损失。我国听力言语残疾人口已达到2000余万,居各种残疾之首。新生儿中极重度聋的发病率约为1／1000,其中半数以上与遗传因素相关。据报道平均每8个人中,就有1人携带隐性耳聋基因。在这些有遗传倾向的耳聋患者中,1％属性连锁遗传,9％属常染色体显性遗传,90％属常染色体隐性遗传。非综合征性耳聋是遗传性耳聋中最常见的类型,大约占遗传性耳聋的80％,综合征性耳聋占20％-30％。遗传性耳聋具有高度的遗传异质性,到目前为止,己定位的耳聋相关基因位点有100多个,其中超过70个耳聋相关基因己被克隆,有超过400种综合征与耳聋相关。估计人类全部基因中有1％的基因参与听力的形成,换言之,这些基因都有可能成为耳聋的致病基因。     

GJB2基因突变在遗传性非综合征性耳聋中的研究进展

遗传性耳聋可分为综合征性耳聋和非综合征性耳聋。在我国GJB2基因突变是最重要的导致遗传性耳聋的因素之一。在常染色体隐性遗传的非综合征性耳聋中,有50%的患者存在GJB2基因突变。在不同种族中GJB2基因的突变位点不同,中国人以235delC突变最常见,其次为299～300delAT、176del 16bp和35delG。目前发现GJB2基因突变不但可引起遗传性耳聋,还可引起获得性耳聋。现就GJB2基因突变致非综合征性耳聋的相关发病机制、临床表型及检测方法等最新研究进展予以综述。     

连接蛋白与遗传性耳聋研究现状和基因治疗的研究展望

遗传性耳聋可分为综合征性耳聋（syndromic hearing impairment,SHI）和非综合征性耳聋（nonsyndromic hearing impairment,NSHI）。综合征性耳聋除听力损伤外,还有非听力方面的症状和体征,约占遗传性耳聋的30%;其余70%为非综合征性耳聋,即只有听力损害,不伴有非听力方面的症状和体征。学语前耳聋中绝大多数属于后者。人类约有15种连接蛋白,现已证实有6种与遗传性耳聋有关。迄今,对非综合征性常染色体显性遗传耳聋（ARNSHL）研究较多的基因是Connexin 26（Cx26）基因,它的高频突变与NSHI密切相关,同时Connexin 26基因突变与常染色体显性遗传性耳聋DFNA3和常染色体隐性遗传性耳聋DFNB1也有关,故称其为耳聋易感基因。本文主要从基因突变类型、器官和组织的表达,以及引起耳聋的机制和相关的治疗研究加以综述,重点探讨以Connexin 26为代表的连接蛋白与遗传性耳聋的关系。     

非综合性耳聋基因及在我国的研究现状

目的：综述已克隆的非综合征性耳聋相关基因，总结这些基因的功能和在耳蜗的表达特点，并介绍我国非综合征性耳聋分子遗传研究现状。方法：资料来源于非综合征性耳聋分子遗传学研究相关献，和国内近年来在本研究领域的成果及作的研究经历。结果：已鉴定和克隆非综合征性耳聋相关基因23个，其中有些基因与非综合征性和综合征性耳聋都相关，或与常染色体显性遗传和常染色体隐性遗传的非综合征性耳聋都相关。耳聋基因在耳蜗具有较特异性的表达方式，根据其特点可进行某些功能分类；在个体的遗传背景中存在影响听力受损程度的与耳聋基因相互作用的基因。高频感音神经性耳聋基因GJB3是由我国实验室克隆，我国学还在一些非综合征性耳聋患中发现GJB2和线粒体基因等突变，目前主要致力于非综合征性耳聋新基因的定位和克隆及耳聋基因的功能研究。结论：继续鉴定和克隆耳聋相关基因是非常值得挑战的一个课题。通过对单基因遗传的耳聋基因进行鉴别，可能有助于更多了解听觉分子过程和耳聋的病理机制。     

COCH基因与DFNA9的相关性研究

耳聋是人类的常见疾病,其导致语言交流障碍,严重影响人们的健康和生活质量。引起耳聋的病因很多,其中遗传因素是不可忽视的病因。目前已发现许多基因突变与耳聋有关,其中常染色体显性遗传非综合征型耳聋基因位点有54个,常染色体隐性遗传非综合征型耳聋基因位点有59个,X连锁遗传位点有8个。其中已克隆的与非综合征型耳聋基因相关的基因包括常染色体显性遗传和常染色体隐性遗传耳聋基因各有21个,其中两者共有基因6个,X染色体上有1个基因[1]。COCH(coagulation factor C homology)基因是人类发现的第1个伴前庭功能障碍的常染色体显性遗传非…     

非综合征显性遗传性耳聋家系致病基因排除性定位研究

耳聋是人类最常见的遗传病之一。20世纪80年代以来，对遗传性聋的基因定位和基因克隆的研究发展飞速。目前国际上已定位了143个非综合征型遗传性聋的基因座，并成功克隆了24个显性遗传性耳聋相关基因。在已登录的常染色体显性遗传聋57个基因座（DFNA1～DFNA57）中，有29个位点（DFNA1～DFNA18，DFNA20，DFNA25～DFNA28,DFNA30，DFNA32，DFNA34，DFNA36～DFNA38）被定位于染色体的狭窄区段，提供用于筛查的微卫星标记物。     

新疆地区汉族遗传非综合征型耳聋人群GJB3基因突变分析

目的:探讨新疆汉族地区缝隙连接蛋白编码基因31(GJB3)突变在中国遗传非综合征型耳聋人群中的特征.方法:应用聚合酶链反应产物商接测序方法对新疆地区对非综合征型遗传性聋患者50名、对照组55名进行GJB3基因编码区突变检测及鉴定编码区突变检测及鉴定.结果:在50名患者中发现GJB3基因的2种单核苷酸改变,其中有1种碱基变化导致了氨基酸的改变,其中一个突变(357C→T)与夏家辉等报道相同;另一个突变形式(766G→A)为本研究首次发现.55名正常对照组中未发现同样突变.结论:国人非综合征型遗传性聋者GJB3基因突变筛查研究发现了一个GJB3基因新的突变形式(766G→A),为进一步开展耳聋相关基因的筛查研究打下了基础.     

重视耳聋基因的临床应用研究

在过去的10年中,遗传性耳聋领域研究飞速发展,自从1995年发现第一个非综合征型耳聋基因,目前已经定位131个非综合征型耳聋基因位点,其中已经克隆的耳聋相关基因有41个（http：／／webhost．ua．ac．be／hhh／）。这些基因涉及编码肌球蛋白在内的细胞骨架蛋白、细胞外基质蛋白、通道和缝隙连接蛋白、转录因子的基因,线粒体基因,还有一些未知功能的基因。这些研究成果已经大大推进了对于听觉、平衡功能过程中分子水平的知识以及耳聋病理机制。     

240例耳聋患者常见耳聋基因筛查分析

目的 分析非综合征型耳聋患者常见耳聋基因突变情况,探讨遗传性耳聋基因芯片检测的临床意义。方法 2013年3-8月来自沈阳市和平区残联的非综合征型耳聋患者240例,患者或监护人签署知情同意后提取被检者外周静脉血基因组DNA,采用晶芯？遗传性耳聋基因检测试剂盒对常见的4个耳聋基因（GJB2、GJB3、SLC26A4以及线粒体12S rRNA）的9个突变位点进行检测。结果 240例受检者中,102例存在被检测基因突变,其中GJB2基因突变44例（18.33%,44/240）,SLC26A4基因突变38例（15.83%,38/240）,线粒体12S rRNA基因突变17例（7.08%,17/240）,GJB3 538 C〉T 1例（0.39%,1/240）。明确诊断为遗传性耳聋60例,提示遗传性耳聋42例,占全部耳聋患者的42.5%（102/240）。结论 非综合征型耳聋患者耳聋基因携带率较高,对高危人群进行耳聋基因突变的筛查和遗传咨询是防止和控制遗传性耳聋、优生优育的重要步骤。     

河南汉族64例非综合征性耳聋的基因芯片诊断

目的 对河南汉族64例非综合征性耳聋患者进行基因芯片诊断. 方法 对河南汉族64个非综合征性耳聋标本采静脉血提取DNA并进行PCR扩增,与晶芯9项遗传性耳聋基因检测试剂盒的芯片微阵列进行杂交,经过耳聋基因专用软件进行扫描并判读结果. 结果 用耳聋基因芯片对64个样本进行耳聋基因突变检测,GJB2、SLC26A4、线粒体12SrRNA、GJB3基因的9个基因位点检出阳性人数22例,占总筛检人数的34.4％,GJB2基因阳性突变总检出率为10.9％ (7/64),SLC26A4基因阳性突变总检出率18.7％(12/64),GJB3阳性突变检出率3.1％(2/64),线粒体12S rRNA阳性突变检出率为1.6％ (1/64),GJB2和SLC26A4基因突变占总突变的86.4％ (19/22). 结论 中国人常见的4个致聋基因突变在河南省人群中都有一定的检出率,GJB2基因235delC突变和SLC26A4基因的2168A＞G突变是常见的突变方式.     

Deafness genes for nonsyndromic hearing loss and current studies in China

Objectives To review the identified deafness genes related to nonsyndromic hearing loss (NSHL) and summarize their expressions and functions in the cochlea and to introduce the current studies of molecular genetics on NSHL in China.Methods The presented data are based on a review of the literature as well as the author’s experience with NSHL and communications with other researchers in China over the past 3 years.Results Currently, 23 deafness genes related to NSHL have been cloned and identified.Some genes are associated with both NSHL and syndromic hearing loss (SHL), in both dominant and recessive deafness.Deafness genes have a highly specific expression pattern in the inner ear.Some functional categories are starting to emerge from a characterization of deafness genes.There are interacting genes in the genetic background that influence the extent of hearing impairment.The GJB3 gene, which is associated with high-frequency hearing impairment, was cloned in a Chinese laboratory.Mutations in some genes, such as GJB2 and mitochondrial 12S rRNA, have been screened in Chinese patients with NSHL.Mapping new deafness gene loci as well as identifying new genes and their functions is an active area of study in China.Conclusions It is challenging for us to continue identifying new deafness genes and analyze gene functions.By identifying genes responsible for monogenic hearing impairment, more insight may be gained into the molecular process of hearing and the pathology of hearing loss.     

Single nucleotide polymorphisms and haplotypes analysis of DFNB1 locus in Chinese sporadic hearing impairment population

Background The DFNB1 locus, which contains the gap junction beta-2 （GJB2） and gap junction beta-6 （GJB6） genes, plays a key role in the nonsyndromic and sporadic hearing impairment. Mutations of DFNB1 result in autosomaJ recessive nonsyndromic hearing impairment （ARNSHI）. Previous researches have identified mutations in GJB2 and GJB6, but single nucleotide polymorphisms （SNPs） of DFNB1 locus have not been studied. So we chose five SNPs to evaluate whether there is difference between deafness people and normal-hearing people in Han Chinese. Methods Five SNPs in the DFNB1 region were examined using a case-control association study between cases with sporadic hearing impairment and controls with normal hearing. The HWEsoft and SHEsis softwares were used to analyze the results. Results Single-locus association analysis showed a positive association for three SNPs： rs9315400, rs2274084 and 235delC. When we compared the distributions of the haplotypes, we also found significant differences between cases and controls in the haplotype combination of rs2274084 and rs2274083 （Х^2=12.978, df=3, global P=0.004719）. Conclusions The haplotypes composed of rs2274084 and rs2274083 suggested that C-C may be a risk haplotype for the sporadic hearing impairment while T-T may be protective against hearing impairment. From that point of view, we can conclude that the SNPs of DFNB1 locus also plays an important role in sporadic hearing impairment cases.     

Phenotype and genotype analysis of a Chinese family with prelingual X-linked hereditary hearing impairment

Background X-linked hearing impairment is clinically and genetically a heterogeneous disease. Although many disorders manifest with hearing loss, a limited number of sex-linked loci and only one gene （POU3F4） have been shown to be implicated in X-linked non-syndromic hearing impairment. In the present study, we have performed a clinical and genetic analysis of a Chinese family with X-linked non-syndromic hearing loss, with emphasis on audiological findings and genomic mapping.
Methods The clinical features of Family JX01 were evaluated by physical and audiometric examination in eighteen family members. Mutation screening of POU3F4 was identified by polymerase chain reaction （PCR） amplification and sequencing. Molecular evaluation consisted of X-chromosome wide genotyping by microsatellite makers （STR）, followed by analyzing using MLINK computer program.
Results Five affected males demonstrated bilateral, symmetrical sensorineural and profound hearing loss. The hearing impairment started prelingual. The female carriers did not have any complain of hearing loss, however, two of them were tested with milder loss with high frequency. No causative mutations in POU3F4 gene were detected by DNA sequencing. Linkage analysis indicated that the responsible gene was linked to locus DXS1227 （maximum Iod score=2.04 at θ=0）.
Conclusions The affected males in Family JX01 have profound prelingual sensorineural hearing impairment. In addition, two female carriers showed mild to moderate hearing losses. However, none of females complained of any hearing loss. Analysis of hereditary deafness in this family mapped most compatibly to the Xq27.2.     

Single nucleotide polymorphisms and haplotypes analysis of DFNB1 locus in Chinese sporadic hearing impairment population

Background The DFNB1 locus, which contains the gap junction beta-2 (GJB2) and gap junction beta-6 (GJB6) genes, plays a key role in the nonsyndromic and sporadic hearing impairment. Mutations of DFNB1 result in autosomal recessive nonsyndromic hearing impairment (ARNSHI). Previous researches have identified mutations in GJB2 and GJB6, but single nucleotide polymorphisms (SNPs) of DFNB1 locus have not been studied. So we chose five SNPs to evaluate whether there is difference between deafness people and normal-hearing people in Han Chinese. Methods Five SNPs in the DFNB1 region were examined using a case-control association study between cases with sporadic hearing impairment and controls with normal hearing. The HWEsoft and SHEsis softwares were used to analyze the results.Results Single-locus association analysis showed a positive association for three SNPs: rs9315400, rs2274084 and 235delC. When we compared the distributions of the haplotypes, we also found significant differences between cases and controls in the haplotype combination of rs2274084 and rs2274083 (X2=12.978, df=3, global P=0.004719).Conclusions The haplotypes composed of rs2274084 and rs2274083 suggested that C-C may be a risk haplotype for the sporadic hearing impairment while T-T may be protective against hearing impairment. From that point of view, we can conclude that the SNPs of DFNB1 locus also plays an important role in sporadic hearing impairment cases.     

Single nucleotide polymorphisms and haplotypes analysis of DFNB1 locus in Chinese sporadic hearing impairment population

Background The DFNB1 locus, which contains the gap junction beta-2 (GJB2) and gap junction beta-6 (GJB6) genes, plays a key role in the nonsyndromic and sporadic hearing impairment. Mutations of DFNB1 result in autosomal recessive nonsyndromic hearing impairment (ARNSHI). Previous researches have identified mutations in GJB2 and GJB6, but single nucleotide polymorphisms (SNPs) of DFNB1 locus have not been studied. So we chose five SNPs to evaluate whether there is difference between deafness people and normal-hearing people in Han Chinese. Methods Five SNPs in the DFNB1 region were examined using a case-control association study between cases with sporadic hearing impairment and controls with normal hearing. The HWEsoft and SHEsis softwares were used to analyze the results.Results Single-locus association analysis showed a positive association for three SNPs: rs9315400, rs2274084 and 235delC. When we compared the distributions of the haplotypes, we also found significant differences between cases and controls in the haplotype combination of rs2274084 and rs2274083 (X2=12.978, df=3, global P=0.004719).Conclusions The haplotypes composed of rs2274084 and rs2274083 suggested that C-C may be a risk haplotype for the sporadic hearing impairment while T-T may be protective against hearing impairment. From that point of view, we can conclude that the SNPs of DFNB1 locus also plays an important role in sporadic hearing impairment cases.     

Single nucleotide polymorphisms and haplotypes analysis of DFNB1 locus in Chinese sporadic hearing impairment population

Background The DFNB1 locus, which contains the gap junction beta-2 (GJB2) and gap junction beta-6 (GJB6) genes, plays a key role in the nonsyndromic and sporadic hearing impairment. Mutations of DFNB1 result in autosomal recessive nonsyndromic hearing impairment (ARNSHI). Previous researches have identified mutations in GJB2 and GJB6, but single nucleotide polymorphisms (SNPs) of DFNB1 locus have not been studied. So we chose five SNPs to evaluate whether there is difference between deafness people and normal-hearing people in Han Chinese. Methods Five SNPs in the DFNB1 region were examined using a case-control association study between cases with sporadic hearing impairment and controls with normal hearing. The HWEsoft and SHEsis softwares were used to analyze the results.Results Single-locus association analysis showed a positive association for three SNPs: rs9315400, rs2274084 and 235delC. When we compared the distributions of the haplotypes, we also found significant differences between cases and controls in the haplotype combination of rs2274084 and rs2274083 (X2=12.978, df=3, global P=0.004719).Conclusions The haplotypes composed of rs2274084 and rs2274083 suggested that C-C may be a risk haplotype for the sporadic hearing impairment while T-T may be protective against hearing impairment. From that point of view, we can conclude that the SNPs of DFNB1 locus also plays an important role in sporadic hearing impairment cases.     

Single nucleotide polymorphisms and haplotypes analysis of DFNB1 locus in Chinese sporadic hearing impairment population

Background The DFNB1 locus, which contains the gap junction beta-2 (GJB2) and gap junction beta-6 (GJB6) genes, plays a key role in the nonsyndromic and sporadic hearing impairment. Mutations of DFNB1 result in autosomal recessive nonsyndromic hearing impairment (ARNSHI). Previous researches have identified mutations in GJB2 and GJB6, but single nucleotide polymorphisms (SNPs) of DFNB1 locus have not been studied. So we chose five SNPs to evaluate whether there is difference between deafness people and normal-hearing people in Han Chinese. Methods Five SNPs in the DFNB1 region were examined using a case-control association study between cases with sporadic hearing impairment and controls with normal hearing. The HWEsoft and SHEsis softwares were used to analyze the results.Results Single-locus association analysis showed a positive association for three SNPs: rs9315400, rs2274084 and 235delC. When we compared the distributions of the haplotypes, we also found significant differences between cases and controls in the haplotype combination of rs2274084 and rs2274083 (X2=12.978, df=3, global P=0.004719).Conclusions The haplotypes composed of rs2274084 and rs2274083 suggested that C-C may be a risk haplotype for the sporadic hearing impairment while T-T may be protective against hearing impairment. From that point of view, we can conclude that the SNPs of DFNB1 locus also plays an important role in sporadic hearing impairment cases.     

Single nucleotide polymorphisms and haplotypes analysis of DFNB1 locus in Chinese sporadic hearing impairment population

Background The DFNB1 locus, which contains the gap junction beta-2 (GJB2) and gap junction beta-6 (GJB6) genes, plays a key role in the nonsyndromic and sporadic hearing impairment. Mutations of DFNB1 result in autosomal recessive nonsyndromic hearing impairment (ARNSHI). Previous researches have identified mutations in GJB2 and GJB6, but single nucleotide polymorphisms (SNPs) of DFNB1 locus have not been studied. So we chose five SNPs to evaluate whether there is difference between deafness people and normal-hearing people in Han Chinese. Methods Five SNPs in the DFNB1 region were examined using a case-control association study between cases with sporadic hearing impairment and controls with normal hearing. The HWEsoft and SHEsis softwares were used to analyze the results.Results Single-locus association analysis showed a positive association for three SNPs: rs9315400, rs2274084 and 235delC. When we compared the distributions of the haplotypes, we also found significant differences between cases and controls in the haplotype combination of rs2274084 and rs2274083 (X2=12.978, df=3, global P=0.004719).Conclusions The haplotypes composed of rs2274084 and rs2274083 suggested that C-C may be a risk haplotype for the sporadic hearing impairment while T-T may be protective against hearing impairment. From that point of view, we can conclude that the SNPs of DFNB1 locus also plays an important role in sporadic hearing impairment cases.