一个中国人裂手足伴并指趾畸形家系的表型和基因型分析

目的 确定一个中国人裂手足家系的致病性基因突变,探讨基因型-表型关系.方法 收集患者及其家庭成员的外周血,提取基因组DNA.采用PCR扩增P63基因和HOXD13基因的外显子,对PCR产物进行双向测序检测基因突变.结果 在所有患者中检测到P63基因第7外显子的杂合型956G→A突变,导致蛋白产物第280位的精氨酸被组氨酸取代(R280H).在正常家庭成员中未检测到该突变.结论 该家族中的患者以对称性裂手足伴并指趾为主要特征,由P63基因的R280H突变所致.     

一个中国手足裂畸形家系的遗传学分析

目的研究中国人手足裂畸形家系产生的分子遗传基础。方法通过X光片对一家系4代手足裂畸形患者进行了临床分析,采集了家系成员中18人的外周静脉血并提取基因组DNA。利用微卫星标记对该家系进行基因组扫描、连锁分析以及单倍型分析,并对于候选区域内的指趾发育相关基因Dactylin(DAC)基因的编码区、外显子/内含子交界区域以及部分的启动子区域进行测序分析。结果该家系大部分患者食指缺失或者发育不全,中指以缺指或以3、4并指出现,脚趾畸形程度略高于手指,表型特征符合已报道的手足裂畸形症的基本特征。两点间连锁分析在D10S192处获得最大的LOD值Z=3.50(θ=0.00),将该家系临床类型确定为SHFM3型手足裂畸形,单倍型分析将该家系的致病基因定位于D10S185和D10S1693之间约21cM的范围内,在对DAC基因测序中,未检测到任何的序列突变。结论通过对家系内表型分析,可将疾病类型确定为典型的手足裂畸形症,并将致病基因定位于10q23-q26约21cM范围内,测序结果显示DAC基因的点突变不是引发该家系手足裂畸形的原因。     

一个常染色体显性遗传非综合征性耳聋家系的HBSY-012家系基因检测及遗传学特征分析

目的 研究常染色体显性遗传非综合征性耳聋家系的HBSY-012家系致病基因的突变位点，分析基因型与异常表型的关系。方法 采集一个常染色体显性遗传性非综合征型耳聋HBSY-012家系患者的临床资料，分析耳聋表型、遗传方式，并绘制家系图。提取家系成员外周血DNA，利用耳聋相关基因靶向测序，对家系成员进行全基因组外显子测序，寻找致病基因，采用Sanger测序技术验证突变位点。结果 HBSY-012家系现存四代共19人，9人诊断为感音神经性聋，耳聋表型特点为语后聋，发病早期呈现高频感音神经性耳聋，双耳对称，随着疾病进展出现渐进性听力下降，且快速下降，并转变成全频受累的极重度感音神经性耳聋。该家系的9例患者均在5～7岁开始出现听力下降，患者中年龄最大68岁，最小10岁。HBSY-012家系系谱分析该家系符合常染色体显性遗传特征。遗传性耳聋基因筛查检测显示EVI5基因NM＿005665:c.2399C>T变异、ANKMY2基因NM＿020319:c.822＿826del变异以及CCDC50基因c.363C>T(p.Leu121Phe)杂合突变，其中CCDC50基因c.363C>T...     

遗传性多发性外生骨疣－大家系的遗传与治疗研究

目的本文对遗传性多发性外生骨疣（hereditary multiple exostoses，简称EXT或HME）一大家系的家系调查、染色体、致病基因的定位以及中西医结合治疗研究进行了回顾总结。方法作者历时15年对一个HME大家系完成了家系调查，绘制了家系谱，对部分成员外周血淋巴细胞常规培养染色体核型G显带分析、致病基因的定位与测序分析，并对部分患者给予中西药物和手术治疗。结果共调查该家族7代1179人，具有亲缘关系成员646人，发现患者44人，37．32％o，男29人，女15人，男女之比1．933：1。8例患者染色体G显带核型均正常，40例成员致病基因测序分析后发现，有13例家系成员含有骨疣致病基因EXT2的突变。应用四环素、糖皮质激素、六味地黄丸治疗21例，有效率达80．95％，手术治疗12例，一次治愈无复发。结论对该HME家系研究已取得一定成果，针对基因异常的药物开发和积极优生学措施有待进一步研究。     

中国人遗传性B型短指(趾)家系中 ROR2基因突变的鉴定

目的　确定一个中国人 B型短指 (趾 )家系中是否存在 ROR2基因突变。方法　从一个中国人B型短指 (趾 )家系的患者外周血中提取基因组 DNA,PCR扩增 ROR2基因外显子 8和部分外显子 9,PCR产物直接测序 ;同时进行 PCR产物 TA克隆和插入片段测序。结果　在患者中发现 ROR2基因第 9外显子1398～ 1399ins A杂合突变 ,与国外发现的致病性突变一致。结论　本文首次报告中国人 B型短指 (趾 )中的 ROR2基因突变。     

一个先天性静止性夜盲症家系致病基因的突变分析

目的 检测和分析河南1个常染色体显性先天性静止性夜盲症( autosomal dominant congenital stationary night blindness,ADCSNB)家系相关基因的致病突变.方法 从该家系14名成员的外周血提取基因组DNA,根据已报道的ADCSNB的3个致病基因的6个相关位点设计引物.利用PCR扩增相关位点所在的外显子,纯化扩增产物后进行正反向测序.结果 在该家系患者的RHO基因中发现了1个c.281C＞T的杂合错义点突变,该突变在蛋白质水平将导致p.Thr94Ile的改变,而在该家系正常成员以及50名正常对照中未发现此突变.结论 RHO基因c.281C＞T突变(p.Thr94Ile)为该家系先天性静止性夜盲症发病的分子遗传学基础.     

一个先天性头皮单纯少毛症家系的临床表型及CDSN基因突变分析

目的 通过对1个先天性头皮单纯少毛症(hypotrichosis simplex of the scalp,HSS)家系的临床特征调查及CDSN基因突变分析,以确定该家系的疾病类型和致病基因并建立产前诊断的方法.方法 经家系调查及临床检查确定疾病类型;抽取3例患者及7名正常家系成员和100名正常对照的外周血提取基因组DNA,PCR扩增CDSN基因的第1、2外显子,用直接双向测序、BLAST比对进行突变分析.结果 家系中3例患者均表现为先天性头皮单纯少毛症,呈常染色体显性遗传;在3例患者的CDSN基因第2外显子cDNA序列发现717C＞G无义杂合突变(Y239X),正常家系成员和对照中均未发现该突变.结论 CDSN基因Y239X无义突变是该家系先天性头皮单纯少毛症的致病突变,此突变是首次在中国HSS疾病人群中报道.     

中国人并多指(趾)畸形家系中HOXD13基因突变及产前诊断

目的对中国山东一个并多指(趾)，又称Ⅱ型并指(趾)，畸形大家系进行致病基因突变的鉴定．确定中国人并多指(趾)畸形家系中是否存在HOXD13基因突变；通过检测突变HOXD13基因对高危胎儿进行产前基因诊断。方法根据家族史、临床体征和手足X线检查进行临床诊断；采集家系成员外周血标本及受检孕妇羊水和绒毛标本，常规提取基因组DNA；设计并合成1对特异引物，通过PCR扩增HOXD13基因第1外显子内多聚丙氨酸链编码序列；PCR扩增片段经琼脂糖凝胶电泳检测，异常扩增片段经TA克隆后测序鉴定；产前诊断中，通过PCR扩增、变性聚丙烯酰胺凝胶电泳和银染检查HOXD13基因内及基因两侧共3个微卫星多态标记进行单体型分析。结果本家系4代54人，患者16人(男6人，女10人)；手足共同表现为：3／4完全并指伴软组织蹼内多指，4／5并趾伴软组织蹼内多趾．外显率为100％，表现度变异明显。上述表现符合典型常染色体显性并多指(趾)的表型特征。对家系中18人(患者9人)进行HOXD13基因分析，结果显示：全部患者多聚丙氨酸链中丙氨酸残基数由正常的15个延长为24个。通过HOXD13基因多聚丙氨酸链延展突变检测和单体型分析，对家系中1女性患者两次怀孕进行产前诊断，发现胎儿均携带突变HOXD13基因。结论首次在中国人典型并多指(趾)大家系中发现HOXD13基因多聚丙氨酸链延展突变；联合HOXD13基因多聚丙氨酸链延展突变检测和单体型分析，首次完成2例并多指(趾)胎儿的产前基因诊断。     

一个中国人并多指(趾)畸形家系中HOXD13基因突变的检测

目的 在一个中国汉族并多指(趾)畸形家系中检测HOXD13基因致病突变.方法 通过PCR扩增HOXD13基因外显子序列,对产物进行直接测序及TA克隆测序寻找致病突变.结果 在患者中发现HOXD13基因外显子1的5'末端丙氨酸重复区内,具有27bp的不完全三核苷酸重复的插入突变,使其多聚丙氨酸链延长了9个丙氨酸残基.结论 HOXD13基因内9个丙氨酸残基的延展突变为该家系的致病突变.     

一个中国人并多指(趾)畸形家系中HOXD13基因突变的检测

目的 在一个中国汉族并多指(趾)畸形家系中检测HOXD13基因致病突变.方法 通过PCR扩增HOXD13基因外显子序列,对产物进行直接测序及TA克隆测序寻找致病突变.结果 在患者中发现HOXD13基因外显子1的5'末端丙氨酸重复区内,具有27bp的不完全三核苷酸重复的插入突变,使其多聚丙氨酸链延长了9个丙氨酸残基.结论 HOXD13基因内9个丙氨酸残基的延展突变为该家系的致病突变.     

A novel homozygous missense mutation in WNT10B in familial split-hand/foot malformation

Split-hand/foot malformation (SHFM) is a rare limb developmental malformation, characterized by variable degree of median clefts of hands and feet due to the absence of central rays of extremities. To date, six different forms of SHFM have been described. Four of these SHFM1, SHFM3, SHFM4 and SHFM5 show autosomal dominant, SHFM6 autosomal recessive and SHFM2 X-linked pattern of inheritance. In this study a large consanguineous Pakistani family, with autosomal recessive SHFM, appeared in the last two generations, was investigated. In total 15 individuals including 9 males and 6 females were affected with the syndrome. Affected members of the family exhibited SHFM phenotype with involvement of hands and feet. Most of the affected members showed syndactyly/polydactyly in hands and feet, dysplastic hand, aplasia of radial ray of hand and cleft foot. Investigating linkage to known autosomal SHFM loci mapped the family to SHFM6 locus on chromosome 12p11.1-q13.13. Mutation screening of the gene WNT10B revealed a novel sequence variant (c.986C>G, p.Thr329Arg) in all affected individuals who were studied. This is the third mutation reported in gene WNT10B causing autosomal recessive SHFM syndrome.     

Fine mapping of the X-linked split-hand/split-foot malformation (SHFM2) locus to a 5.1-Mb region on Xq26.3 and analysis of candidate genes

Split-hand/split-foot malformation (SHFM) is a genetically heterogeneous disorder, with five known loci, that causes a lack of median digital rays, syndactyly, and aplasia or hypoplasia of the phalanges, metacarpals, and metatarsals. In the only known SHFM2 family, affected males and homozygous females exhibit monodactyly or bidactyly of the hands and lobster-claw feet. This family (1) was revisited to include additional subjects and genealogical data. All 39 affected males and three females fully expressed the SHFM, while 13 carrier females examined exhibited partial expression of SHFM. We narrowed the previously linked 22-Mb genetic interval on Xq24-q26 (2), by analyzing additional family members and typing additional markers. The results define a 5.1-Mb region with a new centromeric boundary at DXS1114 and a telomeric boundary at DXS1192. We did not identify mutations in the exons and exon/intron boundaries of 19 candidate genes. These data suggest that the mutation may lie in a regulatory region of one of these candidate genes or in another gene within the SHFM2 region with unclear role in limb development.     

First direct evidence of involvement of a homozygous loss‐of‐function variant in the EPS15L1 gene underlying split‐hand/split‐foot malformation

Split‐hand/split‐foot malformation (SHFM) is a severe form of congenital limb deformity characterized by the absence of 1 or more digits and/or variable degree of median clefts of hands and feet. The present study describes an investigation of a consanguineous family of Pakistani origin segregating SHFM in an autosomal recessive manner. Human genome scan using SNP markers followed by whole exome sequencing revealed a frameshift deletion (c.409delA, p.Ser137Alafs*19) in the EPS15L1 gene located on chromosome 19p13.11. This is the first biallelic variant identified in the EPS15L1 gene underlying SHFM. Our findings report the first direct involvement of EPS15L1 gene in the development of human limbs.     

ED1基因新突变导致无汗型外胚层发育不良

目的鉴定一个无汗型外胚层发育不良(HED)家系ED1基因的突变及探讨基因型与表型之间的关系,为该病的诊断,产前诊断及遗传咨询提供实验依据。方法对一个HED家系进行调查,临床资料收集及采集外周血,抽取基因组DNA;设计ED1基因外显子引物,行先证者DNA PCR扩增及序列测定,发现候选变异后对先证者的父母及120名匹配正常人进行突变位点序列分析;推导的该基因氨基酸序列(突变位点)用Clustal W软件进行多物种对比。结果先证者发现ED1基因c.158T>G(p.Leu53Arg)纯合突变,母亲为c.158T>G(p.Leu53Arg)杂合突变;先证者父亲及120例正常对照的序列分析结果未检测出相应位置突变。讨论 ED1基因突变检测是直接诊断HED有效手段之一,发现的c.158T>G(p.Leu53Arg)为新致病突变。     

The 10q24-linked split hand/split foot syndrome (SHFM3): narrowing of the critical region and confirmation of the clinical phenotype

In this communication we describe the clinical and molecular genetic findings in a family with a variable ectrodactyly linked to SHFM3. This is only the second detailed report of the clinical features of the SHFM3 linked syndrome in a large pedigree. Within this family the expressivity of the condition ranges from the classical ectrodactyly deformity to partial absence of the thumb and agenesis of the distal tip of the index finger. There is discordant limb severity, with the feet more severely affected than the hands. Two individuals have a nail dysplasia indicating the presence of a minor ectodermal component. A cleft palate was present in one individual. Radiological features of family members include short metacarpals with rounded proximal heads, agenesis of the radial ray, epiphysial coning, and an unusual supernumerary ossicle opposed to the distal phalanx of the left thumb. Genetic mapping studies in this family exclude p63 involvement and demonstrate that ectrodactyly in this pedigree is linked to the SHFM3 region on chromosome 10q24. A meiotic recombination event enabled exclusion of a maximum of 1.9 Mb of DNA from the previously known critical region thereby narrowing the critical interval to between D10S1265 and D10S222, with the minimal critical region being between D10S1240 and D10S1267. Further investigations are in progress to identify the gene within the SHFM3 critical region responsible for ectrodactyly.     

湖北土家族一糖尿病伴耳聋家系的遗传学研究

目的分析湖北土家族一糖尿病伴耳聋家系,确定其遗传方式;检测线粒体基因组中tRNAleu（UUR）基因3243A→G突变,阐明该家系患者发病与线粒体基因突变的关系。方法采集家系部分成员外周血提取DNA,利用聚合酶链式反应-限制性片段长度多态性（PCR-RFLP）的分析方法,检测家系部分成员的线粒体基因突变。结果经PCR-RFLP分析,家系中8名患者tRNAleu（UUR）基因均存在3243A→G异质性突变,患者的2名正常后代则没有该突变。结论该家系为母系遗传,线粒体tRNAleu（UUR）基因3243A→G突变是导致患者发病的原因。