一个常染色体显性遗传非综合征型聋家系的听力学及遗传学特征分析

目的 分析一个常染色体显性遗传非综合征型聋家系的听力学和遗传学特征.方法 对收集到的一个常染色体显性遗传非综合征型聋家系成员进行家系调查、听力学检测和全身体格检查,绘制家系图谱,整理、分析家系成员的听力学和遗传学特征;提取外周血DNA,对已知常见耳聋基因GJB2、GJB3、COCH、EYA4以及线粒体DNA全序列进行筛查.结果 该家系由5代53名成员组成,现存4代42人,耳聋患者11人;耳聋表型连续遗传,男女均可患病,符合常染色体显性遗传规律,均表现为对称性语后感音神经性聋(12～36岁之间发病),起初为高频听力下降,随着年龄的增长,逐渐累及中低频听力.已知常见致聋基因全编码序列突变检测分析无阳性发现.结论 该常染色体显性遗传非综合征型聋家系中耳聋者表现为对称性、迟发性、进行性、高频下降为主的语后感音神经性聋.     

常染色体显性遗传非综合征性耳聋家系临床听力学特征分析及致病基因定位研究

目的 分析一个连续六代遗传的耳聋家系临床听力学特征及遗传特征,应用连锁分析的方法定位致聋基因.方法 通过家系调查,对一个高频感音神经性聋家系的资料进行了收集、整理及临床听力学和遗传学特征的分析.对家系成员进行调查并绘制系谱图.对调查的家系成员进行病史采集、体检、纯音测听和声导抗检查.结果 该耳聋家系遗传方式为常染色体显性遗传,耳聋患者表现为语后、迟发、渐进、以高频下降为主的听力损失,早期以高频听力损失为主,随着年龄增长逐渐累及全频听力,听力曲线由下降型变为平坦型.结论 该耳聋家系为常染色体显性遗传方式,表现为高频感音神经性耳聋,通过全基因组SNP扫描及连锁分析,初步定位于4号染色体190384723-190669832区域.     

一个常染色体显性遗传非综合征型聋家系分析

目的分析一个连续5代遗传的常染色体显性遗传性聋家系的临床听力学及遗传学特征。方法对一个常染色体显性遗传高频感音神经性聋家系成员进行全面体检及临床听力学检查,整理、分析家系资料,确定遗传规律,绘制遗传图谱并进行听力学特征分析。应用Sanger测序技术对该家系成员进行候选基因鉴定。结果该耳聋家系遗传方式为常染色体显性遗传,发病年龄各代间较稳定,在30-45岁之间。听力学表型为代代相传、迟发性、渐进性的中度至重度听力损失,患者早期以高频听力下降为主,随着年龄增长逐渐累及全频听力。应用Sanger测序技术进行候选基因鉴定,未发现致聋突变位点。结论该家系遗传学特征符合常染色体显性遗传方式,听力学具有早期高频听力下降并逐渐累及全频的特征,在候选基因中进行测序未发现致聋突变位点。因此希望通过对家系进一步的表型分析或者运用新一代测序技术,可以找到该家系的致聋基因。     

一个中国河北省遗传性低频感音神经性耳聋家系临床表型及遗传学特征分析

目的分析一个常染色体显性遗传性耳聋家系的临床听力学特征及遗传规律。方法对一个国人常染色体显性遗传低频感音神经性耳聋家系的资料进行了收集、整理及临床遗传学特征的分析。对家系成员进行调查并绘制系谱图。对调查的家系成员进行病史、体检、纯音测听、声导抗检查,两名患者进行耳声发射、听性脑干反应、前庭功能及颞骨CT扫描检查以排除听神经病及听觉系统的其他病变。结果该耳聋家系遗传方式为常染色体显性遗传,耳聋患者表现为一种迟发型的、渐进性的、以低频下降为主的听力损失,发病年龄介于10～25岁,早期以低频损失为主,听力曲线呈上升型,随着年龄增长逐渐累及全频听力,听力曲线由上升型变为平坦型。结论该耳聋家系为常染色体显性遗传方式,表现为低频感音神经性耳聋,通过全基因组扫描及连锁分析,有望发现新的低频感音神经性聋的相关基因。     

一个常染色体显性遗传低频感音神经性聋家系听力学及遗传学特征分析

目的分析一个常染色体显性遗传性聋家系的临床听力学特征及遗传规律。方法对一个常染色体显性遗传低频感音神经性聋家系28名成员进行病史采集、体检及纯音测听、声导抗检查并绘制系谱图。其中,5名患者进行耳声发射、听性脑干反应检查,2名患者进行前庭功能及颞骨CT扫描检查以排除听神经病及听觉系统的其他病变。全部成员均应用微卫星标记对DFNA21个位点23个基因进行初步筛查,数据分析采用连锁分析方法。结果该耳聋家系（命名为BJ—L046）遗传方式为常染色体显性遗传,耳聋患者表现为迟发型的、渐进性的、以低频下降为主的听力损失,发病年龄5～28岁,早期以低频损失为主,听力曲线呈上升型,随着年龄增长逐渐累及全频听力,听力曲线由上升型变为平坦型。全部家系成员FNA21个位点23个基因筛查均为阴性。结论该耳聋家系为常染色体显性遗传方式,表现为低频感音神经性聋,数据连锁分析无阳性发现,初步排除了21个DFNA位点23个已知基因。     

常染色体显性遗传非综合征型耳聋家系听力学及遗传学特征分析

目的分析一个连续5代遗传的耳聋大家系的临床听力学特征及遗传规律。方法通过家系调查,对家系成员进行全身系统检查及临床听力学检测,分析遗传规律,绘制遗传图谱并进行听力学特征分析。结果此耳聋家系成员共计35人。其先证者为感音神经性聋,无全身其他系统异常。耳聋遗传方式为常染色体显性遗传,发病年龄各代间较稳定,为15～30岁。听力表型为代代相传、迟发性、渐进性的中度至重度听力损失,听力损失初以高频下降为主,随着年龄增长逐渐累及全频听力,听力曲线由下降型变为平坦型。结论该家系遗传学特征分析符合非综合征型常染色体显性遗传方式,该研究为进一步致病基因的定位与克隆奠定了基础。     

进行性非综合征型聋家系临床表型及遗传学分析

目的分析一个连续五代常染色体显性遗传性非综合征型聋家系的临床表型及遗传学特征。方法对该耳聋家系成员进行病史采集、全身及听力学检查,绘制遗传图谱并进行遗传学特征分析。应用微卫星标记连锁分析方法及外显子序列分析对常染色体显性遗传(DFNA)23个基因的22个位点进行初步筛查。结果该耳聋家系共五代,现存家系成员44人,参与本研究的39人中耳聋患者16人,除1人为语前聋外,其他患者均表现为迟发性、渐进性听力下降,发病年龄介于14～40岁,早期以中频听力下降为主,逐渐累及高频,随着年龄的增长,呈全频听力下降。除DFNA5外,各DFNA位点连锁分析所得LOD值均<-2,提示该家系的致聋基因与这些位点均不连锁。对家系中2例患者和2例正常者DFNA5的所有外显子进行测序分析,未发现突变。结论该家系遗传方式符合常染色体显性遗传规律,表现为以中高频听力下降为主的感音神经性聋;对已知耳聋基因位点进行筛查,未发现明确的阳性位点;通过新一代测序技术进行全外显子组分析可能发现新的感音神经性聋致病基因。     

一个常染色体显性遗传非综合征性聋家系分析

目的:分析一个连续5代遗传的常染色体显性高频听力损失家系的听力学及遗传学特征。方法:通过对家系成员进行全面体检及临床听力学检测,整理、分析家系资料,确定遗传规律,绘制遗传图谱并进行听力学特征分析。应用Affymetrix 5.0SNP芯片对该家系参与连锁分析的32例成员进行全基因组扫描及连锁分析,行致病基因的染色体定位。结果:该耳聋家系(命名为SX-G087)成员共计91例。其先证者为感音神经性聋,无全身其他系统异常。耳聋遗传方式为常染色体显性遗传,发病年龄各代间较稳定,为20～35岁。听力表型为代代相传、迟发性、渐进性的中度至重度听力损失,以高频下降为主,部分患者随着年龄增长逐渐累及全频听力,听力曲线由下降型变为平坦型。应用芯片进行全基因组扫描,1～22号染色体未发现有显著连锁的区段。结论:该家系遗传学特征符合常染色体显性遗传方式,表现为早期高频听力下降并逐渐累积全频的特征,全基因组扫描未发现有显著连锁的区段。因此希望通过对该家系进一步的表型分析或者运用新一代测序技术,可以找到该家系高频感音神经性聋的致病基因。     

一噪声相关常染色体显性遗传耳聋家系遗传性分析

目的分析一个与噪声接触相关的常染色体显性遗传性耳聋家系的听力学及遗传学特征,制定致聋基因鉴定策略。方法对该常染色体显性遗传性耳聋家系进行问卷调查,听力学检测及全身体查,绘制该耳聋家系的遗传图谱,分析其听力学及遗传学特点。应用Sanger测序技术进行候选基因鉴定。结果该家系共5代,进行听力学检测者为13人,听力下降者6人,其中3人有明显的噪声接触史。听力学表现为双侧迟发性感音神经性耳聋,先以高频听力损失为主,随后逐渐加重累及全频听力下降,听力开始下降年龄在16-37岁之间。起病后3年症状明显加重。应用Sanger测序技术进行候选基因鉴定,未发现致聋突变位点。结论这个家系成员为高频听力下降为主的迟发性感音神经性耳聋,符合常染色体显性遗传非综合征型耳聋特点,且怀疑有噪声易感因素。计划下一步通过对家系的表型分析运用新一代测序技术希望鉴定出该家系的致聋基因。     

常染色体显性遗传耳聋家系听力学及遗传学特征分析

目的分析一个常染色体显性遗传性耳聋家系的听力学及遗传学特征,制定致聋基因鉴定策略。方法对该常染色体显性遗传性耳聋家系进行问卷调查,听力学检测,绘制该耳聋家系的遗传图谱,分析其听力学及遗传学特征。结果该家系共5代,进行听力学检测者为33人,听力下降者19人.听力学表现为双侧对称的感音神经性耳聋,以高频听力损失为主,听力损失呈进行性加重,但该家系内2个不同分支听力下降时间明显不同,分别为10-30岁和60岁。该家系A组符合常染色体显性遗传感音神经性耳聋特点,B组符合显性遗传老年性聋特点。结论这个家系的两组成员分别表现出2种不同的听力学表型。A组成员为高频听力下降为主的感音神经性耳聋,符合常染色体显性遗传非综合征型耳聋特点;B组成员为高频听力下降为主的老年性聋,符合显性遗传规律,这2组成员可能分别由不同的致病基因导致,需要根据各自的听力学表型及遗传学特征分别制定耳聋基因筛查策略。     

常染色体显性遗传性聋家系的临床表型及候选致病基因分析

目的探讨线粒体DNA 961delT/insC（n）突变与氨基甙类药物性耳聋的相关性。方法对一个耳聋家系11个成员采集氨基甙类抗生素用药史、进行听力学检查、表型分析,采集外周静脉血样本,从白细胞中提取DNA,用聚合酶链反应扩增线粒体DNA（mtDNA）全序列,对扩增片段进行DNA测序,对发现的基因突变与耳聋表型进行分离分析。结果参与研究的所有9例母系成员均检出mtDNA 961delT/insC（n）突变。有明确氨基甙类抗生素用药史的4例中只有2例耳聋患者,其中1例为用药之前出现的先天性聋,另1例为用药后38年出现的轻度耳聋。突变不与耳聋共分离。结论本研究不支持mtDNA 961delT/insC（n）突变是该家系耳聋的致病突变,mtDNA 961位点附近可能是一个多变异的区域,mtDNA 961delT/insC（n）可能是一个与氨基甙类药物性耳聋不明确相关的多态。     

Audiologic aspects of the search for DFNA20: a gene causing late-onset, progressive, sensorineural hearing loss.

OBJECTIVE: The purpose of this research was to identify the gene responsible for a novel form of nonsyndromic, late-onset, bilateral, progressive, sensorineural hearing loss in a Michigan family of English descent. This report describes the audiologic aspects of the search. DESIGN: Fifty-eight members of the family served as subjects for the study. Family pedigree information was gathered from family interviews, family records, birth and death registration records and census data. Audiologic evaluation was used to describe the hearing loss (phenotype) and classify family members as affected or unaffected based on hearing status. These data then were used in a linkage analysis, a process in which the inheritance of a trait is compared with the inheritance of genetic markers and statistically significant associations are sought. RESULTS: The team mapped the hearing loss to the long arm of chromosome 17 at band 17q25. The pattern of inheritance is autosomal dominant. The search for the gene is continuing using a candidate gene approach. CONCLUSIONS: The hearing loss demonstrated by this mid-Michigan family is a novel form of nonsyndromic, genetic, late-onset, bilateral, progressive, sensorineural hearing loss. The locus of the gene, the 20th for autosomal dominant hearing loss, is at band 17q25 of chromosome 17.     

Autosomal dominant midfrequency hearing impairment

At present, 48 different gene loci have been localised and nine gene mutations have been characterised for non-syndromic hearing impairment. We have identified a large five-generation family with mid-and high-frequency hearing impairment. Family members were considered to be affected only if they had bilateral sensorineural hearing loss below the 90th percentile of an age and sex-dependent control audiometric curve of ISO class B. The inheritance of hearing impairment was autosomal dominant. Of seven affected individuals, six were females and one was male. The hearing loss among affected family members was bilateral, sensorineural and varies from mild to moderate. The type of audiogram was U-shaped. Genetic linkage studies are in progress and our preliminary data show exclusion in chromosome 6, chromosome 11 and chromosome 19 in already known loci for midfrequency hearing impairment. This means, we are mapping a novel locus for autosomal dominant midfrequency hearing impairment.     

Family cancer syndrome: a study of the kindred of a man with osteogenic sarcoma of the mandible

Several familial cancer syndromes have been identified. The syndrome of sarcomas, breast cancer and other neoplasms, known as Li-Fraumeni syndrome, is characterized by several different neoplasms presenting at young ages with autosomal dominant transmission and a high incidence of second primaries. In this paper, we studied six generations (51 people) of the family of a 24-year-old man with osteogenic sarcoma of the mandible. Twelve malignancies in 11 people, including several rare tumors, were revealed. Mean age of presentation was 24 years old. Nine of the 11 patients died of disease. One developed a second primary. Two tumors presented in the head and neck. Transmission was autosomal dominant. The karyotypes of two family members were normal. Identification of Li-Fraumeni syndrome in a family is important in determining appropriate follow-up for the patient and family. Such families are models for studying carcinogenesis.     

Phenotype determination guides swift genotyping of a DFNA2/KCNQ4 family with a hot spot mutation (W276S).

OBJECTIVE: Genotype a family trait with autosomal dominant nonsyndromic sensorineural hearing impairment guided only by the phenotype. STUDY DESIGN: Family study. SETTING: Tertiary referral center. PATIENTS: Fifteen family members. METHODS: In the first phase, sequence analysis was performed on DNA isolated from buccal swabs of the proband and her daughter, guided by the phenotype based on audiometric data that were already available. After detection of the W276S missense mutation in the KCNQ4 gene in both patients, this finding was confirmed in the other affected family members. All participants completed a questionnaire, were clinically examined, and underwent standard pure-tone audiometry. The results were analyzed to refine the phenotypic features of the family trait. RESULTS: All clinically affected participants were carriers of the W276S hotspot mutation in exon 5 of the KCNQ4 gene on chromosome 1p34. Refined phenotypic features confirmed previously described phenotypes of DFNA2 families. CONCLUSIONS: Phenotype determination can be cost saving and very effective in detecting the genotype of autosomal dominant nonsyndromic hearing impairment, especially when phenotype analyses can be performed on data that are already available or easily collected.     

Familial sensorineural hearing loss: a correlative study of audiologic, radiographic, and vestibular findings

A multidisciplinary approach to the study of a family with autosomal dominant sensorineural hearing loss is presented. The affected family members underwent extensive clinical and laboratory evaluation. They were found to have various degrees of bilateral congenital inner ear anomalies as imaged by computed tomography. The degree of structural abnormalities in the inner ears correlated with the severity of hearing impairment. Vestibular testing revealed nonspecific abnormalities generally correlating with audiologic and radiographic findings. This report presents a unique form of sensorineural hearing loss not previously described and is the first in-depth clinical study of nonsyndromal "Mondini dysplasia" occurring in a family.     

Otological manifestations of a new familial polyostotic bone disorder

Fifty members of a family with a unique autosomal dominant bone disease were investigated. Nineteen of the family members were either known to have, or were strongly suspected of having the disease. All but one of these had a hearing loss which was conductive in the younger age group and mixed in the older members. The common finding in those who had middle ear surgery was replacement of the long process of incus by a fibrous band. The histological features were similar to those found in Paget's disease. The age of onset, distribution of lesions and radiographic findings, however, were not typical of this disorder.