角膜炎、鱼鳞病、耳聋综合征的GJB2基因突变研究

目的 检测国内首例先天性角膜炎、鱼鳞病、耳聋综合征(KID)患者的GJB2基因和GJB6基因突变.方法 提取KID综合征患者及家族成员的基因组DNA,采用聚合酶链反应扩增GJB2基因和GJB6基因所有的外显子及其邻近的剪切点,并进行双向直接测序.结果 KID综合征患者的GJB6基因未见变化,GJB2基因核苷酸序列exon2第148位碱基由G突变成A,导致蛋白第50位的天冬氨酸转换成天冬酰胺(D50N).结论 GJB2基因突变可能是本例角膜炎、鱼鳞病、耳聋综合征的致病基因.     

伴皮肤鳞状细胞癌的角膜炎-鱼鳞病-耳聋综合征一例GJB2基因突变研究并文献复习

目的 以GJB2基因为候选基因,研究1例伴有皮肤鳞状细胞癌的角膜炎-鱼鳞病-耳聋综合征患者的分子病因。 方法 收集1例伴有皮肤鳞状细胞癌的角膜炎-鱼鳞病-耳聋综合征患者临床资料,提取患者及其父母的外周血DNA,用PCR扩增GJB2基因的第2外显子后直接测序,检测患者GJB2基因的突变情况。 结果 患者GJB2基因中核苷酸序列外显子2第148位碱基由G突变为A（c.148G > A）,此突变导致GJB2基因第50位氨基酸密码子由GAC替换为AAC,其编码的连接蛋白Cx26第50位天冬氨酸转换成天冬酰胺（p.Asp50Asn ）。此外,GJB2基因外显子2第79位碱基由G突变为A（c.79G > A）,突变导致连接蛋白Cx26第27位的缬氨酸转换成异亮氨酸（p.Val27Ile）。患者的父母未检测到GJB2基因突变位点。文献检索发现国外已有13例角膜炎-鱼鳞病-耳聋综合征伴皮肤黏膜鳞状细胞癌的病例报道,经过基因测序确诊的7例患者均为GJB2基因c.148G > A突变。结论 GJB2基因突变可能是导致本例角膜炎-鱼鳞病-耳聋综合征临床表型的致病原因,c.148G > A突变位置可能与皮肤鳞状细胞癌发生有关。     

皮肤病综合征

20062234角膜炎、鱼鳞病、耳聋综合征的GJB2基因突变研究/张锡宝(广州市皮研所),魏生才,王艳芳…∥中华皮肤科杂志.-2006,39(3).-146~148提取国内首例角膜炎、鱼鳞病、耳聋综合征(KID)患者及其家族成员的基因组DNA,采用聚合酶链反应扩增GJB2基因和GJB6基因所有的外显子及其邻近的剪切点,并进行双向直接测序。结果KID综合征患者的GJB6基因未见变化,GJB2基因核苷酸序列exon2第148位碱基由G突变成A,导致蛋白第50位的天冬氨酸转换成天冬酰胺(D50N)。提示GJB2基因突变可能是本例KID的致病基因。图1表1参10(董妍)20062235Klippel-T…     

角膜炎-鱼鳞病-耳聋综合征

目的:报告1例角膜炎-鱼鳞病-耳聋综合征并进行基因检测。方法:收集1例角膜炎-鱼鳞病-耳聋综合征患儿的临床资料,提取患儿及其家族成员(父母和舅舅)外周血DNA进行基因突变检测。结果:该患儿皮损组织病理检查示鱼鳞病样改变。基因检测示GJB2基因外显子2中的第148位碱基发生G→T杂合突变(c.148G→T),导致其编码的第50位氨基酸发生错义突变(p.Asp50Tyr)。结论:根据患儿典型的临床表现和基因检测结果诊断为角膜炎-鱼鳞病-耳聋综合征。基因检测有助于明确该病诊断。     

先天性角膜炎-鱼鳞病-耳聋综合征GJB2基因突变分析

目的报告1例角膜炎-鱼鳞病-耳聋综合征(Keratitis-Ichthyosis-Deafness syndrome,KID)并进行基因检测。方法收集1例KID患者的临床资料,提取患者及其家族成员(父母和奶奶)的外周血DNA进行基因突变检测。结果患者皮损组织病理检查示角化过度伴疣状增生改变。基因检测示GJB2基因外显子2中的第148位碱基发生G→A杂合突变(c. 148G→A),导致其编码的连接蛋白Cx26第50位氨基酸发生错义突变(p. Asp50Asn)。结论根据患者典型的临床表现和基因检测结果诊断为角膜炎-鱼鳞病-耳聋综合征。基因检测更明确该病诊断。     

皮肤病综合征

20130590角膜炎、鱼鳞病、耳聋综合征一例及GJB2基因突变研究/张玲琳(上海市皮肤病医院),唐黎,王宏伟…∥中华皮肤科杂志.-2012,45(8).-597～599收集1例角膜炎、鱼鳞病及耳聋综合征患者的临床资料,提取患者及家族成员的外周血DNA,用PCR扩增GJB2基因外显子2及其附近的剪切点。DNA直接测序法进行基因突变检测。结果:该患者存在血管     

GJB2基因p.N54H突变致经典型Vohwinkel综合征1例

目的检测1例表现为掌跖角化、假性阿洪及耳聋的Vohwinkel综合征患者的基因变异。方法采集先证者临床信息, 并检测分析基因突变位点。结果先证者临床表现符合经典型Vohwinkel综合征, 基因检测发现GJB2基因c.160A>C(p.N54H)杂合突变, 患者父母及健康对照均未发现此位点变异。结论 GJB2基因c.160A>C(p.N54H)突变首次被发现与经典型Vohwinkel综合征相关, 经典型Vohwinkel综合征及掌跖角皮症伴耳聋之间存在变异位点重叠。     

板层状鱼鳞病两家系TGM1基因的突变

目的:检测2个板层状鱼鳞病家系TGM1基因的突变情况.方法:采用PCR-DNA直接测序方法明确两个家系TGM1基因突变位点,并以免疫组化的方法检测其中一家系患者皮肤中转谷氨酰胺酶的活性.结果:在1个家系的患者中发现TGM1基因第13号外显子第2060位碱基发生G→A纯合突变,使密码子CGT→CAT,导致R687H突变:在另一个家系的患者中发现TGM1基因第4号内含子第一个核苷酸发生G→T及第5号外显子第760位碱基发生G→A杂合突变,分别导致IVS4 1G＞T及D254N的复合杂合突变,其父母均为相应突变的携带者.在50名无关正常人中未发现相同突变.R687H纯合突变患者皮肤转谷氨酰胺酶的活性降低.结论:R687H纯合突变及D254N和IVS4 1G＞T复合杂合突变为新发现的TGM1基因突变位点,可能是引起两家系板层状鱼鳞病患者的病因.     

GJB2基因p.S17F变异引起Olmsted综合征样表现的角膜炎-鱼鳞病-耳聋综合征1例

患儿女,1岁5月龄,肢端及腔口周围角化斑块1年余。皮肤科情况：口周、肛周红色角化斑块、表面有放射状裂隙,掌跖皮肤颗粒状角化,伴趾端残毁。出生后听力检查提示先天性感音神经性耳聋,2岁5月龄时发现角膜穿孔。基因检测：GJB2基因c.50C>T(p.S17F)杂合错义突变。诊断：角膜炎-鱼鳞病-耳聋综合征。p.S17F基因突变可能与Olmsted综合征样特征密切相关,在往后诊断中应注意鉴别。     

二例可变性红斑角化症患者GJB3、4基因突变研究

目的 探讨2例散发可变性红斑角化症（EKV）患者的GJB3和GJB4基因突变。 方法 提取EKV患者、家族成员及正常人基因组DNA,采用PCR扩增GJB3和GJB4基因所有外显子及其邻近的剪切点,进行双向直接测序。结果 1例EKV患者GJB4基因未见变化,GJB3基因的第134位碱基鸟嘌呤（G）被胞嘧啶（C）替换,导致蛋白质第45位的甘氨酸转换成丙氨酸（G45A）。另1例EKV患者GJB3、GJB4均未发现突变。结论 1例 EKV患者存在GJB3基因G45A错义突变。     

有汗性外胚层发育不良一家系基因突变

目的 探讨有汗性外胚层发育不良家系的基因突变及突变类型，为建立本病的基因诊断与遗传咨询提供依据。方法 PCR及Sanger测序技术对有汗性外胚层发育不良家系先证者GJB6基因外显子进行突变鉴定，对可疑的变异位点， Sanger测序检测家系其他成员该位点变异情况。结果 基因检测结果表明，家系先症者GJB6基因错义突变c.31G〉A，该突变导致连接蛋白-30（connexin-30, CX-30）第11位氨基酸由甘氨酸变成精氨酸（p.G11R）。家系的患者均携带此变异，而家系表型正常的个体不携带此变异。结论 GJB6基因c.31G〉A（p.G11R）突变是该有汗性外胚层发育不良家系致病基因突变。     

A rare connexin 26 mutation in a patient with a forme fruste of keratitis–ichthyosis–deafness (KID) syndrome

Background  Keratitis–ichthyosis–deafness (KID) syndrome is a rare ectodermal dysplasia characterized by generalized erythrokeratotic plaques, sensorineural hearing loss, and vascularizing keratitis. Cutaneous changes and hearing loss typically present in early childhood, whereas ocular symptoms present later. Mutations in the connexin (Cx) 26 gene, GJB2 , are now established to underlie many of the affected cases, with the majority of patients harboring the p.D50N mutation.
Methods  A rare patient demonstrating features of incomplete KID syndrome associated with an uncommon Cx26 gene mutation is described.
Results  The patient presented late in adolescence with partial features of KID syndrome. There was limited cutaneous involvement and the rare association of cystic acne. Both hearing impairment and ophthalmic involvement were mild in severity. Genetic mutation analysis revealed a previously described, rare mutation in GJB2 , resulting in a glycine to arginine change at codon 12 (p.G12R).
Conclusions  This report describes a patient exhibiting characteristics suggestive of a late-onset, incomplete form of KID syndrome with the GJB2 mutation (p.G12R). The p.G12R mutation has only been described in one other patient with KID syndrome, whose clinical presentation was not characterized.     

Mutation of GJB2 in a Chinese patient with keratitis–ichthyosis–deafness syndrome and brain malformation

Objective.  Keratitis–ichthyosis–deafness syndrome (KID) is a rare congenital disorder. Mutations in the GJB2 gene have recently been identified as the causative mutations of KID.
Aim.  To define the GJB2 mutation in a Chinese patient with KID and brain malformation.
Methods.  Genomic DNA was extracted from peripheral blood and used to amplify the GJB2 gene. Direct sequencing and endonuclease digestion were used for mutation analysis.
Results.  We identified a heterozygous missense mutation (D50N) in the GJB2 gene in this patient.
Conclusions.  These results indicate that KID syndrome in this patient was caused by a dominant mutation of GJB2 .     

Extending the phenotypic spectrum of keratitis-ichthyosis-deafness syndrome: report of a patient with GJB2 (G12R) Connexin 26 mutation and unusual clinical findings

Keratitis-ichthyosis-deafness (KID) syndrome is a rare ectodermal dysplasia, characterized mainly by the presence of hyperkeratotic skin lesions, neurosensory hearing loss, and vascularizing keratitis. Most mutations that have been discovered as a cause of KID syndrome are autosomal dominant, found in exon 2 of the Connexin (Cx) 26 gene. A G12R (p.Gly12Arg) is a GJB2 mutation reported in only two patients with KID syndrome to date. This article describes a patient with the G12R mutation and KID syndrome with interesting additional features, which include a porokeratotic eccrine ostial and dermal duct nevus, follicular occlusion triad, and unusual persistent oral mucosal papules. We compare this patient's phenotype with the only two other patients described with the same (G12R) mutation. The phenotypic heterogeneity of KID syndrome, inexplicable according to our current understanding of these proteins, speaks to the complexity of the connexin system and its overlapping expression patterns in different tissues.     

Novel mutations in GJB2 encoding connexin-26 in Japanese patients with keratitis-ichthyosis-deafness syndrome

BACKGROUND: Germline missense mutations in the GJB2 gene that encodes connexin-26 (Cx26) have recently been found to be the cause of the keratitis-ichthyosis-deafness (KID) syndrome. OBJECTIVES: To define the GJB2 mutations in three Japanese patients with KID syndrome. METHODS: Genomic DNA was extracted from peripheral blood and used to amplify the GJB2 gene. Direct sequencing and endonuclease digestion were used for mutation analysis and DNA-based diagnosis. RESULTS: We identified two heterozygous mis-sense mutations (D50Y, D50N) in the GJB2 gene in three Japanese patients with KID syndrome. All mutations were located on the first extracellular domain of Cx26. CONCLUSIONS: These data expand the GJB2 mutation database and show that a dominant mutation of Cx26 can cause KID syndrome in Japanese patients.     

Genetic heterogeneity of KID syndrome: identification of a Cx30 gene (GJB6) mutation in a patient with KID syndrome and congenital atrichia

Connexins are integral membrane proteins forming aqueous gap junction channels that allow the diffusional exchange of ions and small metabolites between cells, thus coordinating metabolic activities in multicellular tissues. Dominant mutations in the Cx26 gene GJB2 have been shown to cause keratitis-ichthyosis-deafness (KID) syndrome, palmoplantar keratoderma associated with hearing loss, and Vohwinkel syndrome. Missense mutations in the closely related Cx30 gene GJB6 underlie Clouston syndrome (autosomal dominant hidrotic ectodermal dysplasia). We report a 6-y-old boy with phenotypic characteristics of KID syndrome as well as atrichia. In contrast to other KID syndrome patients, molecular analysis of the connexin gene GJB2 did not disclose a pathogenic mutation, although the patient was homozygous for a common polymorphism (V27I) in the coding sequence of Cx26. Nevertheless, screening of GJB6 revealed a heterozygous missense mutation (V37E) predicted to alter sequence and charge of the first transmembrane helix of Cx30, which was previously implicated in Clouston syndrome (Smith et al, 2002). The presence of a pathogenic Cx30 mutation and the lack of a pathologic molecular change in Cx26 in this patient, whose clinical features predominantly resemble KID syndrome, suggest genetic heterogeneity of KID syndrome and underscore that mutations in Cx30, similar to those in Cx26 or Cx31, can cause different phenotypes. Based on our results, connexin gene mutations should be considered in patients presenting with congenital sensorineural hearing loss and disorders of cornification, and screening of several connexin genes with known cutaneous phenotype, such as those for Cx26, Cx30, Cx30.3, and Cx31, may be required.     

Connexin 26 mutation in keratitis-ichthyosis-deafness (KID) syndrome in mother and daughter with combined conductive and sensorineural hearing loss

Background Keratitis–ichthyosis–deafness (KID) syndrome most commonly results from a mutation in the gap‐junctional protein connexin 26 (Cx26) gene, GJB2. Most cases are sporadic and are associated with sensorineural hearing loss. Methods We encountered a mother and daughter with KID syndrome, and pursued genetic analysis and an extensive hearing loss evaluation. Results The analysis of genomic DNA of both affected patients revealed the mutation 148G → A in GJB2 (D50N). No mutation was found in an unaffected son. Auditory phenotype analysis showed a combined conductive and sensorineural hearing loss in both affected patients. Conclusions This is the second vertical transmission of the D50N mutation. These are the first two cases with combined sensorineural and conductive hearing loss without any significant history of middle ear disease. This points to the possibility that the Cx26 D50N mutation can cause conductive hearing loss.