Clinical features and linkage analysis for a Chinese family with autosomal dominant central areolar choroidal dystrophy

Background A Chinese family with autosomal dominant central areolar choroidal dystrophy （CACD） was identified. The purpose of this study was to collect the clinical findings from the family and to identify the genetic entity by linkage analysis.
Methods Forty-three individuals from 3 generations of the family underwent ophthalmologic examinations, including best-corrected visual acuity, examination of the anterior segments, and inspection of the ocular fundus after pharmacologic mydriasis. Affected family members further underwent color vision test, color fundus photography, fluorescein angiography, automated perimetry, and electroretinography. The family was followed up for 30 months. Peripheral venous blood or buccal swabs were collected from each family member and genomic DNA was extracted. Linkage analysis was performed for candidate genes or loci using microsatellite markers.
Results Seven family members in 3 continuous generations were diagnosed as having autosomal dominant CACD. The family showed progressive development of the disease, affecting both male and female. Age of onset of visual disturbances varied between 11 and 50 years. Phenotypic variability among affected individuals was apparent and ranged from relatively normal-appearing fundus with mild parafoveal pigment mottling to geographic atrophy of the macula. Fluorescein angiography showed hyperfluorescent parafoveal changes in early stage or well-demarcated area of chorioretinal atrophy with enhanced visibility of the residual underlying choroidal vessels in the late stage. Peripheral retina and visual fields were normal in affected individuals. Electroretinogram showed normal or mild reduction in the photopic amplitude. Eight candidate genes （STGD4, RCD1, peripherin/RDS, GUCA 1A, RIMS1, UNC119, GUCY2D, and AIPL1） and two genetic loci （4p15.2-16.3, and 17p13） were excluded to be responsible for the disease by linkage analysis.
Conclusions The clinical findings Of this Chinese family with CACD shared similarities with previously reported families of other ethnicities. Linkage analysis excluded the known genes and genetic loci, indicating genetic heterogeneity of the disease.     

一个常染色体显性视网膜色素变性家系表型分析和RHO基因突变检测

目的分析一常染色体显性视网膜色素变性(autosomal dominant retinitis pigmentosa,adRP)家系的临床表型,确定该家系与视紫红质(rhodopsin,RHO)基因的关系。方法依据RP诊断标准及患者临床表型,确定一连续4代发病的adRP家系遗传的特点;采集家系中13位成员外周血8-10ml,提取基因组DNA;聚合酶链反应(polymerase chain reaction,PCR)扩增RHO基因的第1-5外显子基因片段,产物纯化后直接测序;测序结果与美国国立生物技术信息中心(National Center forBiotechnology Information,NCBI)数据库上公布的核酸标准序列进行比对分析。结果该家系临床特点为所有患者均于10岁左右出现夜盲,1例22岁出现视野损害,2例40岁左右出现视野损害,并且于50岁左右双眼相继发生急性闭角型青光眼和并发性白内障。该家系5例患者在RHO基因外显子、上下游非编码序列以及内含子及外显子拼接部中均未发现碱基改变。结论本研究家系患者存在遗传异质性和表型异质性,RHO基因不是该家系的致病基因。     

异体组织埋藏治疗视网膜色素变性对视力和眼底荧光造影变化的影响

目的　观察异体组织埋藏法治疗视网膜色素变性 (RP)患者视力、视野和眼底荧光血管造影变化 ,探讨治疗作用机理。方法　异体组织埋藏法治疗 5 2例 (10 1眼 )视网膜色素变性患者 ;术前、术后分别检查视力、视野和眼底荧光血管造影。结果　治疗后 ,患者视力显著提高 (P <0 .0 1) ,视野显著扩大 (P <0 .0 1) ,眼底荧光血管造影表现好转 (P <0 .0 5 )。结论　异体组织埋藏法治疗RP可以改善视网膜 -脉络膜血液循环 ,从而改善视网膜 -脉络膜营养状态。     

视紫红质和Peripherin/RDS基因在视网膜色素变性家系中的突变检测

目的 对一常染色体显性视网膜色素变性(autosomal dominant retinitis pigmentosa,adRP) 家系进行视紫红质基因(rhodopsin,RHO)、盘膜边缘蛋白/ 视网膜变性慢基因(Peripherin/retinal degeneration slow,Peripherin/RDS)、视杆外节盘膜蛋白1 基因(retinal outer segment membrane protein 1,ROM1)、神经视网膜亮氨酸拉链基因(neural retinal leucine zipper,NRL) 和视锥杆细胞同源盒基(cone-rod homeobox-containing gene,CRX) 基因的突变检测.方法 采集一连续3 代发病的adRP 家系28 名成员外周血,提取基因组DNA,采用聚合酶链反应(polymerase chain reaction,PCR) 和直接测序技术,对RHO、Peripherin/RDS、ROM1、NRL 和CRX 基因进行检测,结果与标准核酸序列进行比对和分析.结果 该家系成员在RHO、Peripherin/RDS、ROM1、NRL 和CRX 基因中未发现致病突变,但是在Peripherin/RDS 基因第1 外显子和第3 外显子编码区发现4 处单核苷酸改变.结论 该家系在RHO、Peripherin/RDS、ROM1、NRL 和CRX 基因中未检测到致病突变,Peripherin/RDS 基因外显子中4 处单核苷酸改变属于单核苷酸多态性(single nucleotide polymorphisms,SNPs).     

常染色体显性遗传性听神经病家系全外显子组测序分析

目的：在多年围绕1个常染色体显性遗传性非综合征型听神经病家系开展系统分子遗传学研究的基础上,进一步探讨该家系耳聋的致病机制,以期发现新的听神经病致病基因和突变位点。方法：对3例耳聋患者和1例配偶进行全外显子组测序,初步筛选出与家系耳聋相关的候选致病基因。采用PCR-Sanger测序法,检测上述候选基因变异是否与家系表型共分离。最后,以50例与研究家系无关的听力正常人为对照,检测候选致病突变在正常群体中的突变频率和SNPs遗传多态性。结果：全外显子测序分析得到41个候选致病基因突变;用PCR-Sanger测序法对核心家系的9名成员和2名家系外听力正常人进行验证,仅发现1个基因突变（ALOX15B 7942797 C>T）与家系耳聋表型共分离。选取50例家系外正常对照的DNA样本对ALOX15B基因进行PCR扩增和序列分析,结果显示有2例听力正常人也检测到该基因的同一变异,提示该变异为SNPs遗传多态性。结论：对核心家系成员的全外显子组测序分析和Sanger测序法验证未发现有意义的突变位点,排除了该家系耳聋由基因编码区突变及Indels致病的可能性。     

湖北地区一扩张型心肌病家系致病基因筛查

目的 对湖北地区一个扩张型心肌病家系成员进行致病候选基因筛查,寻求家族性扩张型心肌病致病基因,探讨基因型和表型关系.方法 先证者及其家族成员来自湖北省大冶市,先证者于2017年4月在武汉大学人民医院确诊为扩张型心肌病,已有家族成员死亡.详细询问先证者及其家属成员病史、家族史,并进行体格检查、血液指标、心脏超声和心电图检查.对患者的病史、家族史及检查结果分析.与先证者及其家属签订知情同意书,由武汉大学人民医院临床分子诊断中心对先证者候选致病基因全外显子高通量测序,获得可疑突变后,利用Sanger测序验证家系成员是否存在可疑突变.结果 家系先证者(Ⅲ3)和妹妹(Ⅲ2)携带肌联蛋白(TTN)c.100126A>G(P.Thr33376Ala)错义突变.先证者目前心功能下降并伴有恶性心律失常,而其妹妹无明显临床症状,心脏超声检查无异常.结论 本研究发现湖北地区一家族性扩张型心肌病家系存在TTN基因c.100126A>G(p.Thr33376Ala)错义突变,TTN与扩张型心肌病密切相关,是家族性扩张型心肌病重要致病基因.     

视网膜色素变性家系应用助视器的效果随访分析

目的探讨助视器在视网膜色素变性(RP)患者中的应用价值。方法分析一例RP家系的患病家谱、患者的生活视力以及验配助视器后的效果。结果该家系4代人中患病12例,其中3人日常生活视力均≤0.12,应用2.8×2.8倍眼镜式远用助视器后,其康复视力分别达到了0.4、0.4、0.6,摆脱了低视力困扰。结论助视器可提高RP患者的生活视力和生活质量,其临床价值应得到重视。     

Identification of Two Disease-causing Genes TJP2 and GJB2 in a Chinese Family with Unconditional Autosomal Dominant Nonsyndromic Hereditary Hearing Impairment

Background:

There are more than 300 genetic loci that have been found to be related to hereditary hearing impairment (HHI), including 92 causative genes for nonsyndromic hearing loss, among which 34 genes are related to autosomal dominant nonsyndromic HHI (ADNSHHI). Traditional linkage analysis and candidate gene sequencing are not effective at detecting the ADNSHHI, especially for the unconditional families that may have more than one pathogenic cause. This study identified two disease-causing genes TJP2 and GJB2 in a Chinese family with unconditional ADNSHHI.

Methods:

To decipher the genetic code of a Chinese family (family 686) with ADNSHHI, different gene screening techniques have been performed, including linkage analysis, candidate genes screening, high-throughput sequencing and Sanger sequencing. These techniques were done on samples obtained from this family over a period of 10 years.

Results:

We identified a pathogenic missense mutation, c. 2081G>A (p.G694E), in TJP2, a gene that plays a crucial role in apoptosis and age-related hearing loss (ARHL). The mutation was co-segregated in this pedigree in all, but not in the two patients who presented with different phenotypes from the other affected family members. In one of the two patients, we confirmed that the compound heterozygosity for p. Y136* and p.G45E in the GJB2 gene may account for the phenotype shown in this patient.

Conclusions:

We identified the co-occurrence of two genetic causes in family 686. The possible disease-causing missense mutation of TJP2 in family 686 presents an opportunity for further investigation into ARHL. It is necessary to combine various genes screening methods, especially for some unconventional cases.     

Molecular genetic analysis of autosomal dominant late-onset cataract in a Chinese Family

Congenital cataract is a highly heterogeneous disorder at both the genetic and the clinical-phenotypic levels.A unique cataract was observed in a 4-generation Chinese family,which was characterized by autosomal dominant inheritance and late-onset.Mutations in the 13 known genes (CRYAA,CRYAB,CRYBB1,CRYBB2,CRYGC,CRYBA1/A3,CRYGD,Connexin50,Connexin46,intrinsic membrane protein LIM2,cytoskeletal protein BFSP2,the major intrinsic protein-MIP and the heat shock factor HSF4) have previously been demonstrated to be the frequent reason for isolated congenital cataracts,but the exact molecular basis and underlying mechanisms of congenital cataract still remain unclear.This study was designed to find whether these 13 genes developed any mutation in the family members and to identify the disease-causing gene.Polymerase chain reaction (PCR) and direct DNA sequence analysis were carried out to detect the 13 genes.The results showed that no mutation causing amino acid alternations was found in these potential candidate genes among all patients in the family,and only several single-nucleotide polymorphisms (SNPs) were identified.A transitional mutation in the fourth intron of CRYBB2 and some silent mutations in the first exon of BFSP2 and CRYGD were found in the cataract family,but further study showed that these mutations could also be found in normal controls.It was concluded that some unidentified genes may underlie the occurrence of late-onset cataract in this family.A genome-wide screening will be carried out in the next study.     

EPB41基因突变导致遗传性椭圆形红细胞增多症一家系的分子诊断研究

  目的  对临床诊断为遗传性椭圆形红细胞增多症（HE）的一个家系进行遗传学病因分析。  方法  应用靶向捕获及高通量测序技术对先证者和家系中4名成员的外周血基因组DNA进行高通量测序,经过数据分析筛选可能的致病变异,同时使用生物信息学软件对变异进行功能预测,在家系中对检出的可疑致病性变异进行Sanger测序验证。同时对50例健康对照抽取外周血,进行正常人群突变位点检测。  结果  高通量测序结果显示临床表现为中度贫血的先证者和其母在EPB41基因第13外显子均存在杂合c.1215G>A（p.Trp405Ter）无义突变,为功能缺失型突变,有极强的致病性（very strong pathogenicity,PVS1）。该位点G碱基突变为A碱基,导致其编码的蛋白质链第405位的色氨酸的密码子变为终止密码子,使蛋白合成提前终止,形成截短蛋白,部分功能区域丧失。该变异在人群中极为罕见,为尚未报道的致病性突变。Sanger测序结果显示先证者外祖母亦携带这一杂合突变,且在此家系中观察到基因型和表型共分离。50例无亲缘关系的健康对照均未检测到突变。  结论  EPB41基因的c.1215G>A突变是本例HE家系的可疑致病原因。首次在中国HE家系中发现了EPB41基因致病性突变。     

初诊与缓解期AML患者家属心理状况调查比较

目的:比较初诊急性白血病患者家属与缓解期急性白血病患者家属抑郁、焦虑心理状况。方法:对20例初诊急性白血病患者家属进行焦虑自评量表(SAS)、抑郁自评量表(SDS)分析评定;随机选取20例住院的缓解期急性白血病患者家属进行SAS、SDS评定,并行比较两组的结果。结果:白血病患者家属多伴有抑郁情绪,少部分患者家属伴焦虑情绪;初诊急性白血病患者家属全部表现轻中度抑郁,缓解期急性白血病患者家属表现为轻度抑郁,两者差别有统计学意义(P<0.01);初诊急性白血病患者家属少数(15%)有轻度焦虑,而缓解期急性白血病患者家属有25%表现为轻度焦虑,两者差别无统计学意义(P>0.05)。结论:对急性白血病患者家属进行适当心理支持是必要的。     

43例复发性多软骨炎耳部表现并文献复习

目的 总结43 例复发性多软骨炎(relapsing polychondritis,RP) 患者临床特征并与国内外资料比较,提高对该病的认识.方法 结合文献回顾43 例RP 临床资料,重点分析RP 耳部表现及治疗.结果 43 例患者男女发病比例1.5∶1,平均发病年龄40.3(13-72) 岁,平均病程15 个月.以耳部表现起病者17 例(39.5%),病程中累及耳部的38 例(88.4%),其中耳廓软骨炎33 例(76.7%)、咽鼓管功能障碍3 例(7%)、外耳炎6 例(14%)、眩晕4 例(9.3%)、耳鸣12 例(28%)、感音性听觉丧失7 例(16.3%).所有患者均接受糖皮质激素治疗,37 例联合其他免疫抑制剂治疗,出院之前症状均有明显缓解.结论 RP 主要依靠临床症状诊断,实验室及病理学检查对诊断有辅助作用.对于耳部病变者,耳科医师与风湿科医师共同诊治,有助于早期诊断和治疗.     

3个 VHL 综合征家族的基因检测及临床调查

目的：明确 von Hippel-Lindau 综合征(VHL 综合征)家族基因突变及临床表现特点,筛查出家族内基因突变携带者行临床筛查,综合家族发病特点行家族健康指导。方法通过流行病学调查,共3例先证者临床诊断 VHL 综合征。抽取先证者及家族自愿者外周血,应用聚合酶链反应(PCR)体外扩增得到 vhl 基因片段,通过测序得到基因信息;再对家族内具有 vhl 基因突变的携带者进行头颅 MRI、腹部 B 超等对全身多系统行临床筛查;综合家族发病特点给出家族健康指导。结果3例先证者均发现 vhl 基因发生突变,家族1中5例成员基因阳性,突变方式为外显子1 c.330C > A;家族2先证者外显子3488delC;家族3发现7例基因阳性者,突变方式为外显子1 c.233G > A。其中,家族成员1III3、3III1、3III4、3IV3确定为基因突变携带者,临床检查显示其中3例成员已发病,1III3表现为双肾多发囊肿,胰腺多发囊肿;3III1表现为胰腺多发囊肿;3III4表现为视网膜血管母细胞瘤、胰腺多发囊肿,视网膜血管母细胞瘤接受激光治疗。3IV3由于年龄较小,临床检查未见明显异常。所有基因携带者接受规范化随访。结论基因检测可早期确诊 VHL 综合征,临床上对 vhl 基因突变患者需进行严密随访,从而提高患者治疗效果、延长生存期或改善生活质量。     

常染色体显性视网膜色素变性家系基因定位

目的探讨一常染色体显性视网膜色素变性（autosomal dominant retinitis pigmentosa,adRP）家系致病基因与盘膜边缘蛋白/视网膜变性慢基因（eripherin/retinal degeneration slow,RDS）、视杆外节盘膜蛋白1基因（retinal outer segment membraneprotein 1,ROM1）、视锥杆细胞同源盒基因（cone-rod homeobox gene,CRX）、神经视网膜亮氨酸拉链基因（neural retinalleucine zipper,NRL）、鸟甘酸环化酶激活1B基因（guanylate cyclase activator 1B,GUCA1B）、肌动蛋白同源2基因（fascinhomolog 2,FSCN2）和拓扑异构酶结合1基因（topoisomerase I binding,TOPORS）多发突变位点的关系。方法采集一个连续4代发病的RP家系14个成员外周血4~5 ml,提取基因组DNA,采用聚合酶链反应（plymerase chain reaction,PCR）对常见的7个adRP候选基因的17个外显子多发突变位点进行扩增,PCR产物纯化后直接测序,测序结果与美国国立生物技术信息中心（National Center for Biotechnology Information,NCBI）数据库中公布的核酸标准序列进行比对分析。结果该家系视网膜色素变性为常染色体显性遗传,家系成员在RDS、ROM1、CRX、NRL、GUCA1B、FSCN2和TOPORS基因中未发现致病突变,仅在RDS基因第1外显子和第3外显子编码区发现5处单核苷酸改变。结论 RDS、ROM1、CRX、NRL、GUCA1B、FSCN2和TOPORS不是本研究家系的致病基因,RDS基因外显子中的5处单核苷酸的改变为单核苷酸多态性（single nucleotide polymorphism,SNP）。     

云南玉溪市一家族性肥厚型心肌病家系致病基因筛查

目的 对云南省玉溪市一个家族性肥厚型心肌病的家系成员进行候选致病基因筛查, 分析基因型和表型之间的关系, 为家族性肥厚型心肌病的分子遗传学机制研究、早期筛查、早期干预治疗提供重要的理论基础.方法 对家系成员进行详细的病史采集、体格检查、常规十二导联心电图、心脏彩超检查;采集外周静脉血样本进行基因学检测.绘制家系遗传图谱, 分析家系遗传特点、基因型及临床表型.结果 该家系肥厚型心肌病的遗传方式以X连锁显性遗传为主.候选基因筛查发现家系中携带GLA、ZFPM2、SCN5A基因的错义突变, 且翻译的氨基酸发生改变.结论 X连锁显性遗传是该家系HCM主要的遗传方式.GLA c.167G>A (p.Cys56Tyr) 杂合或半合子错义突变可能是该家系肥厚型非梗阻性心肌病的主要致病突变.ZFPM2 c.1332G>C (p.Lys444Asn) 杂合错义突变和SCN5A c.5216G>A (p.Arg1739Gln) 杂合错义突变在该家系中临床意义未明.     

胰岛素受体底物2基因突变可能与青少年起病的成人型糖尿病有关：一例报道及其遗传学分析

青少年起病的成人型糖尿病（MODY）是一类以胰岛β细胞功能障碍为特征的、有较高遗传异质性的单基因遗传糖尿病。截至2022年8月,已发现14种明确的MODY致病基因。本文报道了1例疑似MODY患者,通过外显子组测序鉴定了1个胰岛素受体底物2(IRS2)基因突变,并在患者11名家系成员中进行了验证,提出IRS2基因是一个新的MODY候选致病基因,为MODY的诊断和治疗提供更多的参考资料。     

遗传性长QT综合征合并房颤家系的临床研究

[目的]探讨一个遗传性长QT综合征（LQTS）合并房颤家系的临床特点。[方法]对该家系包括先证者在内的三代44例家族成员进行常规临床检查、心电图、动态心电图、超声心动图等检查。[结果]先证者诊断LQTS合并阵发性房颤。6例临床确诊LQTS,8例疑诊LQTS。先证者母亲有晕厥和房颤病史,包括先证者在内2例LQTS合并房颤,另外1例为持续性房颤合并Ⅲ度房室传导阻滞;阵发性房速2例,有可疑房颤症状2例。2例青少年家族成员心电图表现早期复极综合征,其中1例有晕厥,疑诊LQTS。[结论]LQTS合并房颤是一种少见的临床情况,同时又合并传导阻滞临床罕见。早期复极综合征可能不一定总是良性临床经过。遗传性疾病的家系研究是进一步基因学 研究的基石。     

颗粒状角膜营养不良家系的BIGH3基因突变

目的 以基因突变分析一角膜营养不良家系的致病分子基础.方法 应用PCR产物直接DNA测序及限制性内切酶分析检测家系中7例患者和6例表型正常成员的K3、K12和BIGH3基因突变情况.结果 该家系患者成员在K3与K12基因的编码序列区没有发现突变,而BIGH3基因外显子12存在CGG＞TGG(R555W)突变杂合子,家系表现正常成员及正常对照均无BIGH3基因突变;限制性内切酶分析结果显示突变与疾病表现型呈完全共分离.结论 利用基因突变分析确诊我国首例报道的Meesmann角膜营养不良家系属于颗粒状角膜营养不良,且为BIGH3 R555W杂合突变类型.