EDA基因在4个少汗型外胚层发育不全家系中的检测及分析

目的 对4个少汗型外胚层发育不全家系的EDA基因进行测序分析,研究突变的位置、类型,为临床诊断提供遗传学依据.方法 提取先证者及其亲属的基因组DNA,其中患者5人,无症状者12人,另外抽取100名无先天缺牙家族史的正常成人外周血,提取基因组DNA作为对照,设计EDA基因8个外显子的引物,通过聚合酶链反应和DNA测序的方法与正常序列比对.结果 4个家系的患者均存在EDA基因不同位点的突变,分别为c.466C>T、c.663-697缺失、c.587-615缺失、c.878T>G,携带者存在杂合突变,正常对照不存在以上突变.结论 EDA基因的c.466C>T、c.663-697缺失、c.587-615缺失、c.878T>G突变是导致家系先证者及患者出现少汗型外胚层发育不全的病因.其中,EDA基因的c.663-697缺失、c.587-615缺失、c.878T>G是未报道的新突变.     

Anthropometric and cephalometric measurements in X-linked hypohidrotic ectodermal dysplasia

OBJECTIVE: To describe the somatic development and craniofacial morphology in males affected with hypohidrotic ectodermal dysplasia (HED) and female carriers and to find clinical markers for early clinical diagnosis of possible female carriers. DESIGN: A clinical and radiographic examination of the affected males and the female carriers. SETTING AND SAMPLE POPULATION: Twenty-four affected males and 43 female carriers with a known mutation in the ED1 gene were examined in a dental clinic in either Copenhagen or Aarhus, Denmark. EXPERIMENTAL VARIABLES: Height, body mass index (BMI) and head circumference. Cephalometric analysis of the craniofacial morphology. OUTCOME MEASURE: Data on the somatic and craniofacial development in the affected males and female carriers. RESULTS: No difference was observed regarding body height in the affected males and female carriers, BMI values were lower than the mean in most affected boys and adolescence and head circumference was somewhat decreased in both groups compared to normative data. The cephalometric analysis showed a reduced maxilla length and prognathism, a normal size and shape of the mandible and a reduced sagittal jaw relationship in both HED groups. Furthermore, affected males had a retroclined nasal bone and a more anteriorly inclined maxilla. A short nose, protruding lips, reduced facial convexity and facial height, characterized the soft tissue profile of the affected males. In female carriers, the lips were significantly retruded when compared with controls. CONCLUSION: No specific somatic or cephalometric markers could be observed, in the female carrier group.     

X连锁无汗性外胚叶发育不全家系ED1基因的突变检测

目的探讨国内X连锁无汗性外胚叶发育不全家系中ED1基因的突变情况，为该病的遗传咨询、产前诊断、确诊携带者提供依据。方法收集2个X连锁无汗性外胚叶发育不全家系及1个散发患者的外周血样本，盐析法提取基因组DNA，采用聚合酶链反应（polymerase chain reaction，PCR）和直接测序对ED1基因进行突变检测。结果家系一患者ED1基因第9外显子发生错义突变（1045G〉A），家系二和散发患者ED1基因第3外显子发生错义突变，分别为467G〉A和466C〉T。结论ED1基因的错义突变可导致X连锁无汗性外胚叶发育不全。这3个突变与国外学者的报道一致。     

A novel splicing mutation of ectodysplasin A gene responsible for hypohidrotic ectodermal dysplasia

Hypohidrotic ectodermal dysplasia (HED) is characterized by hypohidrosis, hypodontia, sparse hair, and characteristic facial features. This condition is caused by an ectodysplasin A (EDA) gene mutation. In this study, we examined two HED pedigrees and investigated the molecular genetics of the defect. Direct sequencing analysis revealed a previously unidentified mutation in the EDA splice donor site (c.526 + 1G>A). The function of the mutant EDA gene was predicted through online investigations and subsequently confirmed by splicing analysis in vitro. The mutation resulted in the production of a truncated EDA‐A1 protein caused by complete omission of exon 3. This novel functional skipping–splicing EDA mutation was considered to be the cause of HED in the two pedigrees reported here. Our findings, combined with those reported elsewhere, provide an improved understanding of the pathogenic mechanism of HED as well as important information for a genetic diagnosis.     

Quantification of taurodontism: interests in the early diagnosis of hypohidrotic ectodermal dysplasia

Oral Diseases (2010) 16 , 292–298 Objective: The aim of this study was to provide a quantification of taurodontism in Hypohidrotic Ectodermal Dysplasia (HED) and to report its occurrence in a cohort of HED patients to assess phenotypic–genotypic correlations. Patients and methods: Of 68 HED patients retrospectively reviewed, 16 patients aged 7–51 years were selected and compared with a control sample (n = 351). The pulp surface index of the first lower permanent molar was calculated from the panoramic radiograph of each individual, and statistical comparisons between the HED patients and the control sample were performed. Results: Whatever the genetic disorder, 81.25% of the HED patients exhibited a relative enlargement (≥1 s.d.) of the pulp. Major deviations (>5 s.d.) were respectively related to men affected by large deletion of the EDA gene or missense mutation. The autosomal recessive form was linked to a relative moderate pulp enlargement (3.44 s.d.). In NEMO forms, the increase of pulp size in men appeared to be less marked than in EDA mutations. Conclusion: This study provides for the first time an objective assessment of pulp enlargement in HED patients, and the various degrees of taurodontism depicted could be interesting dental phenotypic markers of HED forms.     

少汗型外胚层发育不良症eda-A1基因突变分析及其真核表达载体的构建

目的克隆少汗型外胚层发育不良症（HED）eda-A1基因并进行突变分析,同时构建eda-A1基因编码序列突变型（M）和野生型（W）的真核表达载体pcDNA3.1（-）-eda-A1-M/W,为进一步明析eda基因的功能奠定基础。方法设计含有BamHⅠ和HindⅢ的酶切位点的引物, 从HED患者和正常人外周血淋巴细胞中提取总mRNA,利用RTPCR法克隆eda-A1（M/W）基因cDNA序列;并运用BamHⅠ和HindⅢ双酶切pcDNA3.1（-）载体和eda-A1基因片段,将eda-A1 （M/W） 插入到pcDNA3.1 （-） 载体中,从而构建新的真核表达载体,命名为pcDNA3.1 （-）-eda-A1-M和pcDNA3.1（-）-eda-A1-W。结果成功克隆少汗型外胚层发育不良症eda-A1基因,并发现未见报道过的907位A→C错义突变,导致306位编码氨基酸由谷氨酰胺变异为脯氨酸;经PCR法、重组载体双酶切法、DNA测序验证,成功构建了pcDNA3.1（-）-eda-A1-W/M的真核表达载体。结论成功构建少汗型外胚层发育不良症eda-A1基因（突变型和野生型）真核表达载体pcDNA3.1（-）-eda-A1-M/W,为进一步研究该基因在牙齿发育中的生物学作用奠定了实验基础。     

外胚层发育不全无汗综合征患者基因突变的检测

目的：检测外胚层发育不全无汗综合征患者的EDA基因的突变。方法：提取外胚层发育不全无汗综合征患者的基因组DNA，采用PCR方法扩增EDA基因的第5、9外显子，直接将PCR产物送测序。结果：确证该患者是X染色体隐性遗传的外胚层发育不全无汗综合征，患者EDA基因的第5外显子存在突变位点：918位碱基C突变为A，致使226位线氨酸变为终止码，结论：该患者是X染色隐性遗传的外胚层发育不全无汗综合征，其EDA基因5外显子存在突变。     

少汗型外胚叶发育不良(HED)儿童的全口义齿修复

目的:研究少汗型外胚叶发育不良儿童的全口义齿修复.方法:结合儿童特点进行全口义齿制作,在6年内连续观察、更换.结果:2例少汗型外胚叶发育不良儿童全口义齿修复,均取得良好的修复效果.结论:儿童全口义齿的制作、使用必须符合儿童的生理特点.     

少汗型外胚层发育不全患者咬合重建1例

少汗型外胚层发育不全（HED）患者常伴有颌间距离丧失、牙槽骨发育不良以及先天缺牙等,修复治疗较难。本文报道1例20岁的HED患者,为其设计上颌固定、下颌套筒冠义齿修复进行咬合重建。1年后复查,患者的义齿使用良好,咬合功能恢复正常。     

无汗性外胚层发育不全患者EDA基因突变检测

目的:检测无汗性外胚层发育不全患者的EDA基因的突变。方法:提取无汗性外胚层发育不全综合症患者的基因组DNA,采用PCR方法扩增EDA基因外显子,直接将PCR产物送测序。结果:该患者EDA基因存在突变:-48位碱基A突变为G。结论:该患者EDA基因存在突变:-48位碱基A突变为G,该突变位点国内外未见报道。     

少汗型外胚层发育不良症患者全唾液分析

目的研究少汗型外胚层发育不良症患者唾液流速和成分变化。方法测量HED男性患者、女性携带者、以及男性、女性正常对照组唾液流速和成分,对结果进行统计学分析。结果HED男性患者（18例）、女性携带者（15例）较正常对照组（男性30例、女性30例）唾液流速低,唾液无机成分和蛋白含量升高,淀粉酶活性降低。结论唾液流速减低,使HED患者更容易患口腔疾病,如龋病、念珠菌感染等;同时,唾液成分的改变也有助于HED的临床诊断。     

少汗型外胚层发育不全1例

少汗型外胚层发育不全是一种起源于外胚层的组织发育异常的先天性遗传性疾病,本文报道1例少汗型外胚层发育不全病例,并就其分子生物学研究进展进行讨论。     

Non-invasive longitudinal assessment of facial growth in children and adolescents with hypohidrotic ectodermal dysplasia

Facial growth patterns in 12 subjects (six boys and six girls) with hypohidrotic ectodermal dysplasia (HED) were analyzed and compared with facial growth patterns obtained in healthy reference peers. All subjects with HED were aged 7 yr (mean age ± standard deviation: 7.08 ± 0.41 yr) at the first examination and 14 yr (mean age ± standard deviation: 14.56 ± 0.34 yr) at the last examination. In each subject, the three-dimensional coordinates of facial landmarks were collected non-invasively at eight subsequent years. The volumes of forehead, nose, maxilla and mandible, upper lips, and lower lips were estimated. For each facial volume, differential values between different time points were calculated individually, separately for the 'childhood' (7–10 yr) and the 'adolescence' (11–14 yr) growth period in both HED and reference subjects. Children and adolescents with HED had a slightly reduced global facial growth in comparison with normal reference peers. The peak mandibular and maxillary development was delayed by approximately 2 yr towards later adolescence. The present non-invasive system seems to be useful for studying longitudinal changes of facial growth in healthy and syndromic subjects.     

少汗性外胚层发育不良患者全外显子组测序分析

目的:对少汗性外胚层发育不良（hypohidrotic ectodermal dysplasia,HED）患者进行基因突变检测及致病性分析,为HED患者的基因诊断提供参考依据。方法:收集2016年8月至2021年8月于北京大学口腔医学院·口腔医院儿童口腔科就诊的临床诊断为HED的患儿及其家系成员为研究对象,对患儿及其家...     

Anomalies of tooth formation in hypohidrotic ectodermal dysplasia

OBJECTIVE: The X-linked hypohidrotic ectodermal dysplasia (HED) is the most common type of ectodermal dysplasia. The clinical identification of possible heterozygous females can be difficult because of the varying degrees of clinical signs caused by X-chromosome inactivation. This study is the first to elaborate on anomalies of tooth formation found in a group of hemizygous males and heterozygous females with known ED1 mutations. These tooth anomalies may be used as dental biomarkers for heterozygous females, enabling an earlier diagnosis, and therefore, better treatment and genetic counselling. METHODS: Anomalies of tooth formation were examined using panoramic radiographs, dental casts and oral photographs in hemizygous males and heterozygous females who were identified by molecular genetic analysis. The results were compared to existing controls and normative data. RESULTS: All affected males had multiple missing permanent teeth and tooth malformations. The heterozygous females had a significantly higher frequency of agenesis of permanent teeth compared to normative data. The heterozygous females had an increased prevalence of tooth malformations and reduced tooth size, especially in the mesiodistal dimension. CONCLUSIONS: We conclude that observed anomalies of tooth formation may be used as dental biomarkers in the clinical identification of potentially heterozygous females.     

Aplasia of submandibular salivary glands associated with ectodermal dysplasia.

We describe a 28-year-old white Caucasian man displaying many of the physical signs of ectodermal dysplasia (ED). An unusual finding was his presentation with xerostomia. Salivary gland imaging techniques revealed aplasia of both submandibular salivary glands and relatively small parotids. The case highlights that hypoplasia and aplasia of exocrine glands could be rare features of ED. In the management of ED, early detection of xerostomia is important to limit any potential damage to the already hypodontic dentition.