X-性联锁遗传鱼鳞病一家系STS基因研究

研究X-性联锁遗传鱼鳞病(XLI)一家系基因突变情况,检测基因突变与临床表现的关系,为进一步开展基因诊断和基因治疗奠定基础.抽取该家系中患者、正常人及与这些家系无关的100例正常人的外周血,提取外周血基因组DNA.应用PCR方法扩增外周血基因组DNA类固醇硫酸酯酶(STS)基因的第1、2和10外显子.结果:该家系中的患者STS基因全部缺失,家系中正常人和与该家系无关的100例正常人未发现这种缺失.该缺失引发出XLI特有的皮肤病变.     

应用多重连接探针扩增技术检测X-性连锁鱼鳞病一家系STS基因

目的: 检测X-性连锁鱼鳞病一家系STS基因突变情况.方法: 提取先证者(男,31岁)及其父母外周血DNA,父母均无鱼鳞病临床表现,运用多重连接探针扩增技术检测所有成员的STS基因是否存在外显子缺失,若无外显子缺失,运用聚合酶链式反应特异性扩增STS基因,检测是否存在基因突变.结果: 家系中先证者为STS基因半合子缺失...     

两个X连锁鱼鳞病家系中类固醇硫酸酯酶基因缺失

检测2个中国X连锁鱼鳞病家系中的基因突变。用PCR方法扩增类固醇硫酸酯酶(STS)基因的10个外显子，并对扩增产物进行测序。第一个家系中先证者的STS基因6、7外显子缺失，第二个家系先证者的整个STS基凶缺失。本研究明确了这两个家系中的基因突变，从而为这两个家系的后代进行产前诊断提供了可能。     

X连锁隐性鱼鳞病基因型表型分析

目的:分析4例X连锁隐性遗传性鱼鳞病(X-linked ichthyosis, XLI)患者的临床表现及遗传变异。方法:从中国汉族人群收集XLI患者,记录临床特征及家系信息,通过全外显子组测序分析患者基因上的单核苷酸变异(SNV)、插入和缺失(INDEL)及拷贝数变异(CNV)。结果:共收集4例XLI患者,均检测到STS基因缺失。其中1例患者同时伴有一个已报道的FLG基因无义突变：c.5368C>T(p.Gln1790Ter),该患者表现类似表皮松解性鱼鳞病症状。结论:XLI临床表现差异较大,全外显子组测序是一种诊断XLI的有效方法。携带FLG基因突变的XLI患者倾向于更重的临床表现。     

表皮松解性角化过度型鱼鳞病一家系K10基因突变的研究

目的:检测一表皮松解性角化过度型鱼鳞病家系K10基因突变位点.方法:提取该家系成员的外周血DNA,采用聚合酶链反应(PCR)及DNA直接测序方法,检测患者角蛋白1(K1)及K10的基因突变.结果:该家系2例患者存在K10基因的杂合点突变,即在K10基因第2140位G→A,导致其第156位的精氨酸变为组氨酸(R156H).结论:K10 R156H是导致该家系2例患者临床表型的特异突变,进一步证实K10基因第156位密码子是突变热点.     

先天性鱼鳞病致病基因研究进展

鱼鳞病由许多型别组成,其中一部分是遗传性疾病.该疾病主要特征是全身皮肤干燥、粗糙和鱼鳞状鳞屑,组织学上绝大部分是角质层增厚.先天性鱼鳞病至少有20种,随着遗传分析技术的进步,此类疾病已经得到了新的认识.该病的发生与组成皮肤屏障的基因突变有关.这些基因编码角质形成细胞有关的结构蛋白、细胞连接蛋白、细胞连接水解、脂质代谢及DNA修复所需酶类.此类疾病由于遗传异质性和临床异质性原因分类复杂.根据遗传模式进行分类,可更好了解基因型-表型之间的关系.     

板层状鱼鳞病一家系TGM1突变基因检测

目的 报道1例有近亲背景的板层状鱼鳞病患者及其家系,并检测其转谷氨酰胺酶Ⅰ编码基因TGM1的突变。 方法 提取板层状鱼鳞病患者及家族成员的基因组DNA,采用PCR 扩增TGM1 基因所有的15个外显子及其邻近的侧翼序列并进行双向直接测序。结果 该板层状鱼鳞病患者TGM1基因第11个外显子的1666位的碱基存在胞嘧啶（C）→胸腺嘧啶（T）突变,使得529位密码子由ACA→ATA,相应氨基酸由苏氨酸（Thr）变为异亮氨酸（Ile）。结论 患者转谷氨酰胺酶Ⅰ Thr529Ile基因突变可能导致其发病。其父母基因型均为该突变的杂合子,近亲婚配促进基因的纯合,增加后代患病概率。     

先天性鱼鳞病致病基因的研究

先天性鱼鳞病是一组疾病，不同类型之间致病基因及发病机制不同。有些鱼鳞病已通过连锁分析的方法定位在染色体的某个区段，有些已经找到突变基因，对这些致病基因及其功能的研究有助于先天性鱼鳞病的诊断、遗传咨询及治疗。     

寻常型鱼鳞病一家系Filaggrin基因突变检测

目的探讨一家系寻常型鱼鳞病(ichthyosis vulgaris,IV)丝聚合蛋白(filaggrin,FLG)基因的突变。方法提取IV患者及其家庭成员和100例健康对照者基因组DNA,采用PCR及直接测序法,对FLG基因已报道的13个突变位点(3321delA,441delA,1249insG,E1795X,S3296X,R501X,2282del4,R2447X,S2889X,7945delA,3702delG,Q2417X,R4307X)进行测序。结果三代7位成员中4例IV患者同时检测到FLG(441delA)基因突变。结论患者FLG(441delA)基因突变可能导致其发病。     

表皮松解性角化过度鱼鳞病一家系

报道表皮松解性角化过度鱼鳞病一家系。家系中无近亲结婚史,2代8人中有5人患病。先证者男,18岁,其母亲46岁,均是出生时即患病,先证者母亲皮疹主要为厚的角质性疣状损害,先证者皮疹主要为糜烂渗出损害,临床与病理均符合表皮松解性角化过度鱼鳞病。口服阿维A胶囊短期内见到明显效果。     

Accuracy of the Clinical Diagnosis of Recessive X-Linked Ichthyosis vs Ichthyosis Vulgaris

The present study analyzes the accuracy of the clinical diagnosis of X-linked ichthyosis (XLI) vs ichthyosis vulgaris (IV), in a sample of Mexican patients. The study was double blind, using steroid sulfatase (STS) activity as the golden standard. Twenty male patients were included; 16 corresponded to XLI and 4 to IV. The clinical diagnosis was correct in 9 of the 16 XLI cases (56%) and in 2 of the 4 IV cases (50%). Some clinical findings in XLI, such as cryptorchidism in patients and delayed labor in their mothers, were important features for diagnosis. Statistical analysis of the results showed: among physicians (n=2) Kappa value 0.50, specific concordance 0.40, and absolute concordance 0.75; other values were sensibility 0.56, specificity 0.50, positive predictive value 0.82, negative predictive value 0.22, accuracy 0.55, prevalence 0.80. In conclusion, the differential diagnosis of XLI and IV is very difficult, and we consider that this is not explained either by personal skills or by other conditions. It could be attributed to the similarities in skin manifestations of these two diseases. The performance of the STS assay is imperative in order to correctly diagnose the disease and offer adequate genetic counseling.     

四种遗传性鱼鳞病基因型与临床表型的相关性分析

目的对四种鱼鳞病(寻常型鱼鳞病;X性-联鱼鳞病;板层状鱼鳞病;大疱性鱼鳞病)的致病基因进行精细定位,并分析其基因型与临床表型的关系。方法对四种鱼鳞病各1例患者进行临床表型分析以及外周血DNA直接测序检测鱼鳞病FLG基因、STS基因、TGM1基因和K1,K10角蛋白基因的突变位点。结果①寻常型鱼鳞病患者在FLG基因的外显子5的第278位有G-T突变,613位有G-A突变。②板层状鱼鳞病患者TGM1基因外显子3的第504位碱基有C-T突变,使第142位氨基酸由精氨酸(R)转变为半胱氨酸(C),即R142C错义突变;外显子7的第1122位碱基有C-T突变,使348位氨基酸由精氨酸(R)突变为终止密码(R348X),导致其编码的蛋白缺失了C端的470个氨基酸。③X-性联鱼鳞病患者STS基因完全缺失。④大疱性鱼鳞病患者外显子5的第242碱基存在A-C突变,外显子6的第599位碱基均存在A-G突变,导致K1蛋白第633位氨基酸由赖氨酸(Lys)变为精氨酸(Arg)。结论鱼鳞病患者临床表型的不同与致病基因的突变位点密切相关。     

Ichthyosis nigricans: Ultrastructural study of the melanin pigmentary disturbances

Summary Hyperpigmented skin from a 10-year-old white boy with ichthyosis nigricans has been studied.Histological and ultrastructural studies reveal that the hyperpigmentation is related to both epidermal and dermal hypermelanosis.Melanocytes are hyperactive. The different stages of melanosome synthesis and melanisation appear to be normal. Increased dermal pigmentation probably results from a dischargement of the melanin granules into the dermis secondary to melanocyte alterations. Ichthyosis nigricans is a typical example of melanin pigmentary disturbances of the skin, resulting from disturbances in the normal interactions between melanocytes and keratinocytes.This work was supported by INSERM (ATP 78-99)     

Analysis of the STS gene in 40 patients with recessive X‐linked ichthyosis: a high frequency of partial deletions in a Spanish population

Background Recessive X‐linked ichthyosis (RXLI) (OMIM 308100) is a genodermatosis characterized by polygonal, dark, adherent and mild‐to‐moderate scales that normally improve during summer. RXLI is caused by a deficiency in steroid sulphatase (STS), whose gene has been located on the X chromosome (locus Xp22.3). Up to 90% of the mutations described in this gene are complete deletions. Objectives Previous reports of partial deletion of STS gene in cases of RXLI prompted us to determine the incidence of these abnormalities in a Spanish population. Methods We have studied exons 1, 5 and 10 of the STS gene by polymerase chain reaction in 40 patients with clinical features of RXLI. Results Our results revealed that 30 patients presented complete deletions (75%) while 10 patients had partial deletions (25%) a rate higher than that reported in the previous studies. Conclusions Amplification of exons 1, 5 and 10 is reliable in screening RXLI in the population studied here. No correlation was found between phenotype and the extent of the deletions.     

Gene diagnosis in X-linked ichthyosis

Summary Three families segregating for X-linked ichthyosis (XLI) were analysed using the full-length STS cDNA probe and an anonymous polymorphic DNA sequence closely linked to the STS gene. In patients from two of the families, submicroscopic chromosomal deletions could be detected using both the STS and the GMGX9 (DXS237 locus) probes. Patients in the third family showed the same hybridization pattern as healthy males following molecular hybridization with either of the probes. The results of DNA analysis (indirect geno-type diagnosis) agree well with those based on the arylsulfatase C/-gal determination and prove the reliability of the biochemical test. Both methods are discussed for carrier detection, prenatal diagnosis, and genetic conselling.     

X linked recessive ichthyosis: Current concepts

In the present review, we describe the most importantaspects of the X-linked ichthyosis(XLI) and make a compilation of the some historic details of the disease. The aim of the present study is an update of the XLI. Historical, clinical, epidemiological, and molecular aspects are described through the text. Recessive XLI is a relatively common genodermatosis affecting different ethnic groups. With a high spectrum of the clinical manifestations due to environmental factors, the disease has a genetic heterogeneity that goes from a point mutation to a large deletion involving several genes to produce a contiguous gene syndrome. Most XLI patients harbor complete STS gene deletion and flanked sequences; seven intragenic deletions and 14 point mutations with a complete loss of the steroid sulfatase activity have been reported worldwide. In this study, we review current knowledge about the disease.     

X连锁鱼鳞病并发Meleda角化病一例临床特征及SLURP-1和STS基因突变分析

目的 报道1例X连锁鱼鳞病并发Meleda角化病,并检测其基因突变.方法 收集临床资料,提取患儿及其父母外周血基因组DNA,PCR扩增SLURP-1和STS基因全部外显子及其侧翼序列,以100例健康人作为对照,对扩增产物行琼脂糖凝胶电泳检测,并对SLURP-1基因扩增产物进行DNA测序.结果 患儿躯干、四肢泛发规则排列的棕褐色或黑色多角形鳞屑,掌跖、肘膝、腹股沟、肛周红斑,过度角化,向背侧延伸,诊断为X连锁鱼鳞病并发Meleda角化病.基因检测提示,STS全基因缺失;SLURP-1基因第3外显子第286位核苷酸发生C→T纯合突变(c.286C＞T),导致其编码蛋白质在第96位氨基酸出现终止改变(p.R96*),其父母均为c.286C＞T杂合突变携带者.健康对照未发现此突变.结论 该患者携带STS全基因缺失和SLURP-1基因纯合无义突变,可能是导致X连锁鱼鳞病并发Meleda角化病的原因.     

MBTPS2基因新发突变致毛囊性鱼鳞病-脱发-畏光综合征一例

患者,男,4岁。脱发、全身丘疹伴畏光4年。基因检测示患儿MBTPS2基因有1个半合子突变,即c.3G>C(p.M1I)。母亲该位点杂合变异,父亲该位点无变异,诊断为毛囊性鱼鳞病-脱发-畏光综合征。