播散性浅表光线性汗孔角化病致病基因的定位

目的 对播散性浅表光线性汗孔角化病(DSAP)的致病基因进行定位。方法 收集一个DSAP家系成员的血样抽提基因组DNA,选用12号染色体长臂上已知致病区域的7个微卫星标记进行基因扫描,并用LINKAGE软件(5.1Version)对基因分型结果进行连锁分析。结果 连锁分析结果发现本家系在微卫星标记D12S79的两点最大LOD值为5.15(θ=0.00)。结论 DSAP致病基因位于12号染色体的长臂上。     

全基因组扫描定位遗传性对称性色素异常症易感区域

目的 确定遗传性对称性色素异常症易感区域.方法 用覆盖全基因组22条常染色体的402个微卫星标记对2个遗传性对称性色素异常症大家系进行全基因组扫描,利用Linkage软件(5.10Version)和Cyrillic软件(2.01Version)进行连锁和单倍型分析.结果 常染色体显性遗传模式,外显率为100%时,在1号染色体上的微卫星标记D1S2343处获得最大累积LOD积分为8.85(重组率θ=0.00),其相邻2个标记D1S2696和D1S2345处的最大累积LOD积分分别为4.60(重组率θ=0.10)和8.54(重组率θ=0.00).单倍型分析将易感区域缩小至D1S2696和D1S2635之间11.6cM处.结论 染色体1q11-1q21区域存在遗传性对称性色素异常症易感基因.     

多发性家族性毛发上皮瘤致病基因的确定

目的 对多发性家族性毛发上皮瘤一家系进行基因定位及候选基因突变检测。方法 共用18对覆盖9p21和16q12-q13的微卫星标记对一个多发性家族性毛发上皮瘤家系进行局部基因组扫描,并用Linkage软件进行两点参数连锁分析,最后PCR扩增CYLD1基因的17个编码外显子及其邻近剪接子并进行双向直接测序。结果 ①两点参数连锁分析在常染色体显性遗传模式下,外显率为99.9%、基因频率0.00001时在D16S3068位点处得出LOD值=3.31(θ=0.00),排除与9号染色体连锁;②突变分析在CYLD1基因第18号外显子出现连续的4个碱基缺失,即c.2355-2358delCAGA。结论 多发性家族性毛发上皮瘤存在着遗传异质性,本家系的致病基因位于16q12-q13,而不在9p21。     

采用微卫星标记法对白癜风易感基因的初步筛查研究

目的：对收集的白癜风38家系183人进行基因精细定位，以期识别白癜风的致病基因。方法：收集白癜风患者及其家系成员的临床资料及血液样本，抽提外周血基因组DNA，选用荧光标记引物及微卫星标记，用Genescan和Genotyper软件进行基因分型，用Linkage软件包进行连锁分析，明确致病基因的区域，并对22q12进行精细定位。结果：发现白癜风致病基因与微卫星标记D22s1163处获得最大连锁值（NPL=2．22，P=0．008，HLOD=1．64，α=53％）。结论：染色体22q12上可能存在广东汉族人的白癌风易戚基呙．     

一雀斑家系遗传连锁分析

目的 报道1例雀斑及其三代家系，并对其致病基因进行遗传连锁分析。方法 选取位于4q和1号染色体的微卫星标记对该家系进行致病基因定位研究，用ABI3730测序仪进行微卫星标记的基因分型，利用Linkage软件（5.10 Version）和Cyrillic软件（2.01 Version）进行连锁和单倍型分析。结果 该家系在常染色体显性遗传模式下，外显率为99.9%时，排除该家系与4号染色体的连锁，在1号染色体上的微卫星标记D1S2635和D1S2844处获得可能连锁的证据，最大LOD值为1.50（重组率θ = 0.00）。单倍型分析将该家系可能的致病基因定位在微卫星标记D1S2624和D1S2799之间12 Mb区域内。结论 雀斑存在遗传异质性。在该家系中，本病可能的致病基因存在于染色体1q22-q24的21.2 cM区域内。     

6号染色体上可能存在银屑病易感基因

目的 研究中国人寻常型银屑病与6p21.3区域内的六个微卫星标记和4q上的两个微卫星标记是否连锁,以寻找银屑病易感基因位点。方法 利用选取的微卫星位点作为标记,采用微卫星荧光标记-基因扫描及分型技术,选取205例经确诊并符合寻常型银屑病诊断标准的患者,对其中14个银屑病家系进行连锁分析。结果 在研究的家系中未发现4q上的微卫星标记与银屑病易感基因之间的连锁,而在染色体6p21.3区域存在着与之有连锁关系的微卫星标记位点(在D6S273位点上两点分析最大LOD值为1.26)。结论 本研究表明在中国人银屑病患者中,染色体6p21.3区域可能存在银屑病易感基因。     

遗传性对称性色素异常症一家系致病基因的定位和突变研究

目的 探讨遗传性对称性色素异常症家系的致病基因。方法 明确先证者的临床诊断后,收集该家系成员的血样抽提基因组DNA,应用基因分型和连锁分析的方法进行基因定位,并对该定位区域内DSRAD基因直接测序,分析其突变位点。结果 基因分型和连锁分析将该家系的致病基因定位于1号染色体,和已知报道的区域一致。突变研究发现该家系所有患者的DSRAD基因2号外显子均携带CAA→TAA的突变,使得517位氨基酸由谷氨酰胺变成中止密码子。结论 该遗传性对称性色素异常症家系中的患者存在DSRAD基因的无义突变。     

Marie Unna遗传性稀毛症的遗传异质性

目的对中国汉族人Marie Unna遗传性稀毛症进行基因组精细定位,从而为进一步找到该病的致病基因奠定基础。方法用覆盖8p21的18个微卫星标记对2个家系进行局部基因组扫描,利用Linkage软件(5.10版)和Cyrillic软件(2.02版)进行连锁和单倍型分析。结果家系1在常染色体显性遗传模式、外显率为99.9％时,在8号染色体上的微卫星标记D8S298和D8S1725处获得LODS(连锁分数)为3.01(θ=0.00)；单倍型分析将其定位于D8S282～D8S1839之间的1.1 cM内。家系2的连锁分析排除与8p21连锁。结论 Marie Unna遗传性稀毛症存在遗传异质性。     

角化性皮肤病

20051038 播散性浅表汗孔角化病的基因定位/王霍英(山东省立医院皮肤科),张莉,孙志坚…//中华皮肤科杂志.-2004,37(10).-563-565 收集山东籍一家系6代共254人中的现症者14 例,采到11例患者及21例正常人的血样,分离抽提基因组DNA,选用382对来自常染色体的荧光标记引物, 进行全基因组扫描,基因分型后进行连锁分析,明确了致病基因区域,对其中10对引物进行精细定位。结果     

一遗传性单纯少毛症家系的基因定位

目的：确定一遗传性单纯少毛症家系的致病基因。方法：通过定位候选克隆技术，用ABI公司的商品化微卫星标记，进行全基因组扫描，明确致病基因的区域。结果：在微卫星标记D13S217处得到最高IDD值3．74（重组率θ=0．00）。结论：本研究将该遗传性单纯少毛症家系的致病基因定位于13号染色体上。     

A novel locus for disseminated superficial porokeratosis maps to chromosome 18p11.3

Disseminated superficial porokeratosis (DSP) is a rare autosomal dominant epidermal keratinization disorder of lesions characterized by cornoid lamella with parakeratosis, hyperkeratosis, and loss of granular layers. The genetic basis for this disease is unknown. Through a proband with a diagnosis of DSP, we identified a large four-generation Chinese family with multiple DSP-affected members from Anhui province in China. After excluding the linkage of the disease phenotype to two known loci for disseminated superficial actinic porokeratosis in this family, we performed a genome-wide linkage analysis using 387 microsatellite markers and identified a novel disease locus for DSP at 18p11.3. Our subsequent fine mapping and haplotype analyses further narrowed down the disease locus into an 18.7 cM region between the telomere and D18S391 with a maximum two-point LOD (logarithm of the odds) score of 4.82 (theta =0.00) at D18S1138. Therefore, this study provides strong linkage evidence for a DSP locus at 18p11.3.     

Identification of a novel locus for Marie Unna hereditary hypotrichosis to a 17.5 cM interval at 1p21.1-1q21.3

Marie Unna hereditary hypotrichosis (MUHH) is a rare autosomal dominant disorder characterized by coarse, wiry, twisted hair developed in early childhood and followed by the development of alopecia. A locus for this disorder was localized to chromosome 8p, but no gene responsible for it has been identified.To map and determine whether MUHH is a genetically heterogeneous disorder and identify the disease gene locus in a four-generation Chinese family with MUHH. We performed a genome-wide scan in this family. Two-point linkage analysis was performed using Linkage programs version 5.10 software and haplotype was constructed with Cyrillic Version 2.02 software. We failed to confirm the previous locus for MUHH at chromosome 8p and obtained the conformed evidence for linkage at chromosome 1. Two-point logarithm of odds ratio scores > or =3 were observed at markers D1S2746 and D1S2881. Haplotype analysis localized this locus to a 42 Mb region. The previous results and this study have shown that MUHH is a genetically heterogeneous disorder. Our family was mapped to a 17.5 cM region between markers D1S248 and D1S2345.     

A novel locus (DSAP2) for disseminated superficial actinic porokeratosis maps to chromosome 15q25.1-26.1

BACKGROUND: Disseminated superficial actinic porokeratosis (DSAP) is a chronic cutaneous disorder characterized by multiple superficial keratotic lesions surrounded by a slightly raised keratotic border. It develops in teenagers in sun-exposed areas of skin and usually follows an autosomal dominant inheritance pattern. The first locus for DSAP was localized to chromosome 12q23.2-24.1, but no gene responsible for porokeratosis has been identified to date. OBJECTIVES: To determine whether DSAP is a genetically heterogeneous disorder and to identify the disease gene locus in a three-generation Chinese family with DSAP. METHODS: Genetic linkage analysis was carried out in this family using 15 microsatellite markers between D12S1671 and D12S369 on chromosome 12q, followed by a genome-wide scan with 382 microsatellite markers from the autosomes. RESULTS: Genetic linkage analysis with chromosome 12q markers suggested that the locus in this family is not linked to chromosome 12q. A genome-wide scan and fine mapping finally localized the locus for DSAP in this family to a 6.4-cM region between markers D15S1023 and D15S1030 at chromosome 15q25.1-26.1. This DSAP locus was named DSAP2. CONCLUSIONS: The previous results and this study have shown that DSAP is a genetically heterogeneous disorder; a novel locus for DSAP, termed DSAP2, was mapped to a 6.4-cM region between markers D15S1023 and D15S1030.     

Refined localization of a punctate palmoplantar keratoderma gene to a 5.06-cM region at 15q22.2-15q22.31

BACKGROUND: Punctate palmoplantar keratoderma (PPK) is a rare autosomal dominant cutaneous disorder characterized by numerous hyperkeratotic papules distributed on the palms and soles. Two loci for punctate PPK were recently found to be located on 8q24.13-8q24.21 and 15q22-15q24. However, no genes for this disease have been identified to date. Objectives To refine the previously mapped regions and to identify the disease gene locus in a four-generation Chinese family with punctate PPK. METHODS: Genetic linkage analysis was carried out in this family using microsatellite markers on chromosomes 8q and 15q. Two-point linkage analysis was performed using Linkage programs version 5.10 and the haplotype was constructed using Cyrillic version 2.02 software. RESULTS: We failed to confirm our previous locus at 8q24.13-8q24.21, but significant evidence for linkage was observed in the region of 15q with a maximum two-point LOD score of 5.38 at D15S153 (theta = 0.00). Haplotype analysis localized the punctate PPK locus within the region defined by D15S651 and D15S988. This region overlaps by 5.06 cM with the previously reported punctate PPK region. CONCLUSIONS: This study refines a disease gene causing punctate PPK to a 5.06-cM interval at 15q22.2-15q22.31.     

Identification of a locus for disseminated superficial actinic porokeratosis at chromosome 12q23.2-24.1

Disseminated superficial actinic porokeratosis is an autosomal dominant cutaneous disorder characterized by many uniformly small, minimal, annular, anhidrotic, and keratotic lesions. The genetic basis for this disease is unknown. Using a genomewide search in a large Chinese family, we identified a locus at chromosome 12q23.2-24. 1 responsible for disseminated superficial actinic porokeratosis. The fine mapping study indicates that the disseminated superficial actinic porokeratosis gene is located within a 9.6 cM region between markers D12S1727 and D12S1605, with a maximum two-point LOD score of 20.53 (theta = 0.00) at D12S78. This is the first locus identified for a genetic disease where the major phenotype is porokeratosis. The study provides a map location for isolation of a gene causing disseminated superficial actinic porokeratosis.