一个并指(趾)多指(趾)家系的 HOXD13基因突变研究

目的 研究一个中国人并指(趾)多指(趾)(synpolydactyly，SPD)家系的临床特征，检测患者中是否存在同源盒D13基因(homeobox D13，HOXD13）突变。方法 现场调查获取临床资料和19个家系成员的外周血液标本；PCR扩增HOXD13基因突变热点序列进行突变检测；并扩增全编码区用于检测是否存在其他位点的突变；采用2％琼脂糖凝胶电泳初步分析PCR产物，5％聚丙烯酰胺凝胶电泳分离突变片段，纯化后将所有产物直接测序进行基因检测。结果 患者HOXD13基因第1外显子额外插入了编码8个丙氨酸残基的序列，可认为是正常基因中编码第5～12丙氨酸残基序列的异常重复。结论 证实该家族畸形可由HOXD13基因的多聚丙氨酸链扩展突变引起。     

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.     

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.     

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.     

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.     

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.     

Esophageal atresia/tracheoesophageal fistula and proximal symphalangism in a patient with a NOG nonsense mutation

Esophageal atresia and tracheoesophageal fistula (EA/TEF) are relatively common malformations of the human foregut. The etiology remains incompletely understood with genetic causes identified in a small minority of affected patients. We present the case of a newborn with type C EA/TEF along with proximal symphalangism found to have a de novo NOG nonsense mutation. Patients with chromosome 17q deletions including the NOG gene have previously been reported to have EA/TEF but mutations in the gene have not been identified in patients with this malformation. This case provides evidence that haploinsufficiency for NOG may be the cause for EA/TEF in the 17q deletion syndrome and suggests that the clinical spectrum of NOG-related symphalangism spectrum disorders may include EA/TEF.     

Mutations of the NOG gene in individuals with proximal symphalangism and multiple synostosis syndrome

Proximal symphalangism is an autosomal-dominant disorder with ankylosis of the proximal interphalangeal joints, carpal and tarsal bone fusion, and conductive deafness. These symptoms are shared by another disorder of joint morphogenesis, multiple synostoses syndrome. Recently, it was reported that both disorders were caused by heterozygous mutations of the human noggin gene (NOG). To date, seven mutations of NOG have been identified from unrelated families affected with joint morphogenesis. To characterize the molecular lesions of proximal symphalangism, we performed analyses of NOG in three Japanese individuals with proximal symphalangism. We found three novel mutations: g.551G>A (C184Y) in a sporadic case of symphalangism, g.386T>A (L129X) in a familial case of symphalangism, and a g.58delC (frameshift) in a family with multiple synostosis syndrome. Characteristic genotype-phenotype correlations have not been recognized from the mutations in the NOG gene.     

Novel point mutations in GDF5 associated with two distinct limb malformations in Chinese: brachydactyly type C and proximal symphalangism

Growth/differentiation factor 5 (GDF5) is a secreted growth factor that plays a key regulatory role in embryonic skeletal and joint development. Mutations in the GDF5 gene can cause different types of skeletal dysplasia, including brachydactyly type C (BDC) and proximal symphalangism (SYM1). We report two novel mutations in the GDF5 gene in Chinese families with distinct limb malformations. In one family affected with BDC, we identified a novel nonsense mutation, c.1461T > G (p.Y487X), which is predicted to truncate the GDF5 precursor protein by deleting 15 amino acids at its C-terminus. In one family with SYM1, we found a novel missense mutation, c.1118T > G (p.L373R), which changes a highly conserved amino acid in the prodomain of GDF5. We transfected COS-7 cells with retroviral constructs to express human wild-type or mutant GDF5 cDNAs. The mature GDF5 protein was detected, as in the wild-type, in supernatant derived from the p.L373R mutant GDF5 transfected cells, but not in the supernatant from the p.Y487X mutant transfected cells, indicating that the two mutations led to different fates of the mutant GDF5 proteins, thereby producing distinct limb phenotypes. Wei Yang and Lihua Cao contributed equally to the work.     

Identification of a novel NOG gene mutation (P35S) in an Italian family with symphalangism

Symphalangism (SYM or SYM1) is an autosomal dominant disorder characterized by multiple joint fusions. The disease is caused by mutations of the NOG gene, that maps to chromosome 17q22. So far, only six independent NOG mutations have been identified. We have analysed an Italian family in which father and son had bilateral symphalangism and detected a novel NOG mutation (P35S), originated in the father from a c.914C>T transition. A different mutation in the same codon (P35R) has been previously described. Comparison between different noggin gene hortologs shows that codon 35 is conserved. Therefore, this codon should play an important role in NOG gene function. This is the first mutation described for NOG after the initial report of NOG mutations being causative of SYM.     

Tarsal‐carpal coalition syndrome: Report of a novel missense mutation in NOG gene and phenotypic delineation

We report a family of Indian origin presenting with Tarsal‐carpal coalition syndrome (TCC), which is a rare genetic disorder of skeletal abnormalities, inherited in autosomal dominant manner. In this family, three individuals (mother and two children) were found to be similarly affected with slight intrafamilial individual variability in the phenotype. Sanger sequencing revealed a novel heterozygous missense mutation in NOG gene (NM_005450.4:c.611G>A) in all the affected individuals of the family. Until now only six mutations have been reported in different families affected with TCC syndrome worldwide. This report further delineates the phenotypic spectrum of this rare disorder with the addition of a new variant to the mutation spectrum.     

一个近亲婚配家系中的一种P基因新突变

目的在DNA水平上对1个有2例患者的姨表兄妹近亲婚配家系中的眼皮肤白化病患者进行分型诊断。方法用PCR扩增先证者P基因及TYR基因各外显子、外显子-内含子交界区及3＇端和5＇端非翻译区，以DNA序列测定技术检测基因突变，以DNA测序技术和限制性内切酶酶切法检测该家系其他成员及群体中正常人的相应基因位点。结果先证者和其白化病妹妹为P基因A787T突变纯合子，其父母和表型正常的弟弟均为A787T突变杂合子。先证者TYR基因未见突变。群体中102名表型正常者中无A787T突变等位基因。结论在基因水平确定我国存在眼皮肤白化病Ⅱ型，同时发现了一种P基因病理性新突变。     

一个X-连锁视网膜色素变性中国家系的RPGR基因的新突变

目的 对中国人X-连锁视网膜色素变性一家系进行分子遗传学检测，报告RPGR基因突变。方法 首先对该家系X染色体进行致病基因的连锁分析，然后用单链构象多态性技术和直接DNA测序方法进行基因突变分析。结果 连锁分析在多态性微卫星遗传标记DXSS012和DXS8025产生正的Lod值分别为2．41（Zmax=2．40，θ=0）和1．26。进一步单倍型分析确定该家系致病基因位于Xp21．1，与RP3连锁。用RPGR基因突变分析，在外显子ORF15＋483－484发现GA缺失，引起阅读框架的改变，该基因缺失突变在家系中共分离。结论 报告了中国人X-连锁视网膜色素变性RPGR基因外显子ORF15＋483-484的GA缺失突变，丰富了中国人RPGR基闪突变谱，为今后研究X-连锁视网膜色素变性的基因奠定基础。     

一个有三例女性X-连锁肾上腺-脑白质营养不良杂合子患者家系基因突变分析

目的 对1个有3例女性杂合子患者的X-连锁肾上腺-脑白质营养不良(X-linked adrenoleukodystrophy,X-ALD)家系进行基因突变分析.方法 提取1例患者的外周血白细胞总RNA,以此为模板,采用长链逆转录-PCR技术,分4个片段扩增ABCD1基因(X-ALD疾病基因)编码序列并对其PCR产物进行直接测序.通过PCR和限制性内切酶分析患者及其家庭成员相应的基因组DNA片段,进一步确证所发现的基因突变.对突变及其对ALD蛋白结构的影响进行生物信息学分析.结果 在患者A月CD1基因第1外显子的第283位密码子发现1个新的错义突变:CAC→CGC(p.H283R),此突变使相应DNA片段的1个Msl Ⅰ酶切位点消失,其子不存在此突变.突变所改变的氨基酸残基在进化上高度保守.p.H283R突变位于ALD蛋白的跨膜结构域,可引起该分子跨膜区整体结构的改变.结论 在国内首次报道了3例杂合子女性X-ALD患者,并在其家系发现了1个新的ABCD1基因突变,即p.H283R突变.     

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。