两个斑驳病家系KIT基因突变研究

目的 对2个斑驳病家系进行致病基因突变分析,为患者及其家系成员提供遗传咨询和生育指导.方法 分别采集家系1两例患者(先证者及其父亲)、家系2先证者及3名表型正常家系成员的外周血,提取外周血DNA和RNA.应用PCR、逆转录PCR及测序等技术,从基因组水平和表达水平对此两家系先证者和患者进行KIT基因诊断,并初步探讨检测到的突变对KIT基因功能的影响.结果 家系l中两例患者KIT基因均存在IVS12+ 2_+7delinsACATCTTTA的杂合突变,该突变在cDNA水平导致KIT基因c.1765-1779del突变,在氨基酸水平导致p.Gly592Ala/del:E12突变,使得KIT基因剪切位点发生改变,即其中一条cDNA第12外显子被跨越、未转录.家系2中先证者KIT基因存在c.2401A＞C突变,3位表型正常的家系成员未见该突变.结论 确诊了两个斑驳病家系的致病原因.家系1患者KIT基因均存在IVS12+ 2_+ 7delinsACATCTTTA的杂合突变,该突变为人类基因突变数据库未记载的、新的剪切突变;家系2先证者KIT基因存在c.2401A＞C突变,结合3位表型正常的家系成员KIT基因未见c.2401A＞C突变,推测该突变为先证者患斑驳病的致病突变可能性大.为此两家系进行遗传咨询和产前诊断提供了理论依据.     

Identification of mutations in Danish choroideremia families

We have searched for mutations in the choroideremia gene (CHM) in patients from 12 Danish families in which CHM is segregating. Employing polymerase chain reaction (PCR), single strand conformation polymorphism (SSCP) analysis, and direct DNA sequencing, different mutations have been identified in 6 patients. All the mutations will interfere with the correct translation of the mRNA predicting a truncated protein or no gene product at all. © 1993 Wiley-Liss, Inc.     

两个新RUNX2基因突变引起家族性锁骨颅骨发育不全

目的 探讨RUNX2基因突变在锁骨颅骨发育不全病因研究中的意义及两个中国家族性锁骨颅骨发育不全家系发病的分子机制.方法 提取收集到的2个锁骨颅骨发育不全家系中4例患者和4名家系健康成员、102名无关正常对照外周血基因组DNA,应用PCR扩增产物双向直接测序方法 检测RUNX2基因第1～7外显子及相邻侧翼区的DNA序列,测序结果 与RUNX2基因正常序列对比分析.对发现的突变位点用酶切方法 证实.结果 测序结果 发现一家系中两例父子患者的RUNX2基因第1外显子发生错义突变c.346T＞A(W116R),该错义突变通过Bsr Ⅰ限制性内切酶对PCR扩增产物行酶切分析得到进一步确认.另一家系中两例患者的RUNX2基因第3外显子发生无义突变c.610A＞T(K204X).在两个家系中的正常家系成员和无关正常对照RUNX2基因DNA序列中没有发现上述突变.结论 通过RUNX2基因,检测在中国人群中发现两个RUNX2基因新致病突变,扩展了遗传性锁骨颅骨发育不全的基因突变谱,对阐明该病发病机制及其基因诊断和遗传咨询有重要意义.     

GLA基因的新突变出现在两个典型Fabry家系

目的 报告2个Fabry家系的GLA基因突变特点。方法 2个经临床和病理检查证实的Fabry家系，家系1中连续3代有12人发病，均表现为发作性肢体疼痛；家系2中连续5代有8人发病，多数患者在经末期出现显著的多器官损害表现。对2个家系中的先证者和部分亲属进行PCR扩增其GLA基因的所有7个外显子包括侧翼序列，对PCR产物直接测序。结果 先证者1的GLA基因第1外显子G132T（TGG→TGT）突变，造成W44C替换；先证者2的第6外显子G874C（GCT→CCT），造成A292P替换。两个先证者的母亲都有同其儿子一样的突变，且均为杂合性。结论 经文献检索，两个Fabry家系各存在一个新的GLA基因点突变。同一基因的不同位点的突变导致的临床表现存在很大的差异。由于女性患者和男性一样出现症状，推测这可能是等位基因随机失活导致的显性遗传表现。     

常染色体显性成人多囊肾病两家系PKD1、PKD2基因的突变鉴定

目的 鉴定两个常染色体显性成人多囊肾病家系的致病突变.方法 采用酚氯仿法提取家系成员及无亲缘关系的100名健康对照个体的外周血白细胞DNA,PCR扩增先证者致病基因PKD1、PKD2的所有外显子序列及其侧翼内含子剪切区域,直接测序确定DNA序列的变异.通过家系和正常对照的比较分析,对检测到的变异是否与疾病相关进行了初步探讨.结果 在两个家系中共检测到5个序列变异:PKD1:c.2469G＞A,PKD1:c.5014_5015 delAG,PKD1:c.10529C＞T,PKD2:c.568G＞A和PKD2:c.2020-1_2020 delAG.其中PKD1:c.2469G＞A和PKD2:c.2020-1_2020 delAG为新发现的变异.此外,检测到的移码突变和剪切突变未见于家系中健康成员及无亲缘关系的正常对照.结论 PKD1:c.5014_5015 delAG和PKD2:c.2020-1_2020 delAG分别为家系A和B的致病突变,且PKD2:c.2020-1_2020 delAG为先证者新发生的突变.     

一个先天性静止性夜盲症家系致病基因的突变分析

目的 检测和分析河南1个常染色体显性先天性静止性夜盲症( autosomal dominant congenital stationary night blindness,ADCSNB)家系相关基因的致病突变.方法 从该家系14名成员的外周血提取基因组DNA,根据已报道的ADCSNB的3个致病基因的6个相关位点设计引物.利用PCR扩增相关位点所在的外显子,纯化扩增产物后进行正反向测序.结果 在该家系患者的RHO基因中发现了1个c.281C＞T的杂合错义点突变,该突变在蛋白质水平将导致p.Thr94Ile的改变,而在该家系正常成员以及50名正常对照中未发现此突变.结论 RHO基因c.281C＞T突变(p.Thr94Ile)为该家系先天性静止性夜盲症发病的分子遗传学基础.     

Genetic heterogeneity in LEOPARD syndrome: two families with no mutations in PTPN11

LEOPARD syndrome (lentigines, electrocardiographic conduction abnormalities, ocular hypertelorism, pulmonary stenosis, abnormal genitalia, retardation of growth, and sensorineural deafness) is an autosomal dominant condition. The main clinical features include multiple lentigines, cardiovascular defects, and facial anomalies, some of which are shared with Noonan syndrome (NS). Recent reports have shown that LEOPARD syndrome can be caused by mutations in PTPN11, the gene in which mutations can produce NS. Here we report the findings of mutation screening and linkage analysis of PTPN11 in three families with LEOPARD syndrome. We identified a novel mutation in one family. The mutation (1529A>C) substitutes proline for glutamine at amino acid 510 (Gln510Pro). No variations in sequence were observed in the other two families, and negative LOD scores excluded linkage to the PTPN11 locus, showing that LEOPARD syndrome is genetically heterogeneous.     

10个中国汉族寻常型鱼鳞病家系的FLG基因突变分析

目的 对10个寻常型鱼鳞病(ichthyosis vulgaris,Ⅳ)家系的FLG基因进行突变检测,并分析中国汉族人Ⅳ患者FLG基因的突变热点.方法 用聚合酶链反应扩增10个Ⅳ家系的所有患者及正常成员FLG基因的全部外显子,对扩增产物直接进行DNA测序检测突变,同时选取100名无亲缘关系的正常人作为对照.结果 在7个家系中发现了3种FLG基因的致病突变,包括c.3321delA、c.5757delCCAG和c.8138C＞T(p.S2706X),其中有两例患者的突变类型为3321delA的纯合突变,在另外3个家系中未发现FLG基因的突变.所有家系的正常成员和100名正常对照均未发现c.5757delCCAG和c.8138C＞T(p.S2706X),而在2名正常对照中发现其携带c.3321delA杂合突变.结论 在中国汉族Ⅳ家系检测到3种FLG基因的突变类型,其中c.3321delA是最常见的突变类型(46.9％).首次发现c.5757delCCAG和c.8138C＞T(p.S2706X)突变与Ⅳ相关.部分家系未检测到FLG基因突变,推测可能由其他致病基因导致.     

一个非综合征型唇腭裂家系的致病基因鉴定

目的对一个非综合征型唇腭裂家系进行分子遗传学研究,探寻其致病原因。方法对该家系成员进行详细的体格检查和既往史调查,排除综合征型唇腭裂。对该家系1例患儿的基因组DNA进行全外显子组测序及生物信息学分析。筛查到候选致病基因突变位点后,采用Sanger测序对该家系成员及100名健康对照个体进行共分离分析和人群验证分析。结果全外显子组测序及疾病共分离分析显示,该家系患者IRF6基因第4外显子存在c.253A>G(p.Cys85Arg)变异,且该突变未在健康对照个体中检出,文献尚未见报道。结论IRF6基因第4外显子c.253A>G错义变异是导致该家系发病的原因。     

Identification of two novel mutations in the OCRLI gene in Japanese families with Lowe syndrome

Kubota T, Sakurai A, Arakawa K, Shimazu M, Wakui K, Furihata K, Fukushima Y. Identification of two novel mutations in the OCRL1 gene in Japanese families with Lowe syndrome. Clin Genet 1998: 54: 199–202. 0 Munksgaard, 1998
The oculocerebrorenal syndrome of Lowe (OCRL) is a rare X-linked disorder with features of congenital cataracts. Fanconi syndrome of the renal tubule, and mental retardation. The OCRLI gene has been positionally cloned and shown to encode a phosphatidylinositol 4.5–biphos-phate-5–phosphatase. OCRL is thus thought to be an inborn error of inositol polyphosphate metabolism. We analyzed the gene in two Japanese OCRL patients and their families by DNA sequencing and mismatch polymerase chain reaction (PCR) followed by restriction digestion. A novel nonsense mutation (C1399T) replacing the glutamine of codon 391 (Gln 391 Stop) was identified in exon 12 in 1 patient and also in his mother. A novel missense mutation (C1743G) was identified in exon 15 in the second patient, his mother and maternal grandmother. The missense mutation predicts a substitution of serine for arginine (Ser 505 Arg) in a domain highly conserved among the inosi-tol-5–phosphatase family. Our observations expand the range of OCRLI mutations that cause Lowe syndrome. and will be useful for genetic counseling in these two Fdmilies.     

Van der Woude综合征家系IRF6基因突变分析

目的研究Van der Woude综合征（Van der Woude syndrome，VWS）干扰素调节因子6（interferon regulatory factor 6，IRF6）基因突变。方法提取3个VWS家系成员基因组DNA，聚合酶链反应扩增IRF6基因9个外显子及其侧翼内含子序列，直接测序对患者IRF6基因进行突变的检测。结果在3个家系患者IRF6基因中共发现国际上尚未报道的3个突变：无义突变981（T→A）（Cys327X）和1234（C→T）（Arg412X）；错义突变1214（T→C）（Met405Thr）。结论IRF6基因突变可能是VWS发病原因。     

Unilateral localized conjunctival amyloidosis in a patient with a history of contralateral orbit/eyelid lymphoma

Amyloidosis is a disorder characterized by the deposition of insoluble abnormal proteins in the extracellular space. It may occur as a localized lesion or as a systemic disease involving multiple organs and systems. Localized conjunctival amyloidosis is rare and is less frequently associated with systemic involvement. Although amyloidosis itself is a benign lesion involvement of multiple organs and systems is associated with poor prognosis. Diagnosis of amyloidosis is made on biopsy specimens with Congo red staining for the appearance of apple-green birefringence under polarized light microscopy. Liquid chromatography tandem-mass spectrometry (LC-MS/MS) is much more sensitive in diagnosing amyloidosis and can determine the type of amyloid deposit. Here we reported a case of conjunctival amyloidosis in a 52?year-old male patient who was presented with left lower eyelid swelling to our medical center. He has a complicated past medical history of anti-phospholipid antibody syndrome, Buerger's disease (thromboangitis obliterans), and small cell lymphoma (SLL) of the right orbit/eyelid. The patient received radiation to the right orbit to treat SLL with therapy completed one and a half years prior to presentation. Physical examination revealed a firm, raised yellowish colored lesion in the left lower conjunctiva. The conjunctival lesion was biopsied, and tissue sections were examined with Congo red stains and LC-MS/MS analysis. The biopsy showed amyloid deposits without evidence of malignancy, and the type of proteins in the deposit was immunoglobulin light chain (AL) of kappa type. A complete work up was taken for possible systemic involvement of amyloidosis and results were all negative. To our knowledge, this is the first case of localized conjunctival amyloidosis with a history of contralateral orbit/eyelid SLL.     

Analysis of DSPP gene mutation in a Chinese pedigree affected with hereditary dentinogenesis imperfectaCSCD

Objective: To analyze the clinical phenotype of a Chinese pedigree affected with hereditary dentinogenesis imperfecta and mutation of dentin sialophosphoprotein (DSPP) gene. Methods: Affected members underwent intraoral photography, dental film and panoramic radiography. Genomic DNA was extracted from peripheral venous blood samples. Coding regions of the DSPP gene were subjected to PCR amplification and Sanger sequencing. Functional effect of the mutation was predicted with SIFT and PolyPhen-2. The tertiary structure of wild type and mutant proteins were predicted by Swiss-Port. Results: A heterozygous c. 50C>T (p. P17L) mutation was identified in exon 2 of the DSPP gene in the proband and her father. The same mutation was not found among 200 unrelated healthy controls. The Pro-17 residues and its surrounding positions in DSPP are highly conserved across various species. The mutation was predicted to be damaging to the structure of DSPP protein. Conclusion: The c. 50C>T (p. P17L) mutation of the DSPP gene probably underlies the disease in this pedigree. Above finding has expanded the spectrum of DSPP gene mutations and provided a basis for genetic counseling and prenatal diagnosis for this family. © 2018 MeDitorial Ltd. All rights reserved.     

三个角膜营养不良家系的TGFBI基因突变

目的 筛查3个角膜营养不良家系患者TGFBI基因突变.方法 采集患者外周静脉血,提取基因组DNA,采用直接测序对TGFBI基因全部17个外显子以及外显子内含子拼接部进行序列分析.结果 3个家系中两个家系表型为格子样角膜营养不良1型(1attice corneal dystrophy type I,LCD I)和格子样角膜营养不良3A型(lattice corneal dystrophy type ⅢA,LCDⅢA),另外1个家系为Avellino角膜营养不良(avellino corneal dystrophy,ACD).在两个LCD家系中分别检出编码子R124C和H626R突变,而在ACD家系中检出R124H突变.结论 TGFBI基因是引起角膜营养不良的致病基因.R124和H626是角膜营养不良的突变热点.     

一例成骨不全家系致病变异的鉴定及胚胎植入前遗传学检测

目的:明确一例成骨不全(osteogenesis imperfecta,OI)家系的致病变异并为其提供胚胎植入前遗传学检测(preimplantation genetic testing,PGT)。方法:应用高通量测序结合Sanger测序的方法鉴定患者的候选变异,用直接检测变异的方法对胚胎进行PGT检测,同时筛查囊胚的...     

CDKN2A mutations in Spanish cutaneous malignant melanoma families and patients with multiple melanomas and other neoplasia

The CDKN2A gene has been implicated in cutaneous malignant melanoma (CMM) in about 40% of families with linkage to chromosome 9p21, while a small proportion of families have mutations in the CDK4 gene. In order to estimate the importance of these genes in the predisposition to CMM in Spanish families and patients we have analysed, by SSCA, a total of 56 subjects belonging to 34 CMM families, and nine patients with multiple CMM and other neoplasia. We have detected germline CDKN2A mutations in six out of the 34 families (17%). A frameshift mutation (358delG) and four missense mutations (G59V, G101W (two cases), D84Y, and R87W) were identified. Five CMM patients from different families (14%) carried the A148T variant, which is known not to affect p16 activity. No mutations were detected in the patients with multiple CMM or other neoplasms. We have not found mutations either in exon 1 beta of the CDKN2A gene or in exon 2A of CDK4. Linkage analysis of the 9p21 region showed exclusion for one of the families for CMM and for four families for CMM/dysplastic naevi. This study indicates a small role for CDKN2A in Spanish CMM families and suggests that other genes are also responsible for CMM predisposition.     

五例戊二酸血症I型患者GCDH基因突变的分子诊断CSCD

目的探讨5例戊二酸血症I型（glutaric acidemiatype I,GA—I）患者的GCDH基因突变情况,为临床诊治提供参考依据。方法应用Sanger测序法对泉州地区5例GA—I患者GcDH基因的所有外显子及侧翼内含子进行测序,并对测得序列进行分析,以寻找可能的致病突变位点。结果5例患者均检测到GCDH基因突变,共检测到4种突变位点,包括2种错义突变[c．532G〉A（P．G178R）、C．533G〉A（P．G178E）]和2种移码突变Ee．106—107delAC（P．Q37fs＊5）、C．1244—2A〉c]。其中,c．1244—2A〉C突变频率最高～C106—107delAC为未见报道的新突变,MutationTaster软件预测其为致病性突变。结论本研究分析了5例戊二酸血症I型患者的GCDH基因突变情况,从基因水平上证实了临床诊断,发现1个新的GCDH基因突变位点,丰富了GCDH基因的突变谱。     

两例Cornelia de Lange综合征患儿的临床表现与基因突变分析

目的对两例疑诊为Cornelia de Lange综合征（CdLS）的新生儿进行基因突变检测。方法抽取患儿及其父母的静脉血样,提取DNA,采用目标区域序列捕获及高通量测序技术对CdLS的相关基因（NIPBL、SMCIA、SMC3、RAD21和HDAC8）进行测序,用Sanger测序法对可疑突变进行验证。结果在两例患儿的NIPBL基因中分别检测到c．7219C〉T（P．R2407X）杂合无义突变和C．7015_7024delGATcAGcAAC（P．D2339Lfs＊4）杂合移码突变,后者为尚未报道的致病性突变。未发现sMC1A、SMC3、RAD21和HDAC8基因的致病性突变。结论NIPBL基因的c．7219C〉T和c.7015_7024delGATCAGCAAC突变可能是两例患儿的发病原因。     

Analysis of TGFBI gene mutation in a Chinese pedigree affected with lattice corneal dystrophyCSCD

Objective: To explore the clinical features and mutation of TGFBI gene in a Chinese pedigree affected with lattice corneal dystrophy (LCD). Methods: Genomic DNA was extracted from 35 members including 11 patients from the pedigree. The 17 exons and splicing region of introns of the TGFBI gene were amplified by PCR. The products were directly sequenced and compared with GenBank database to identify potential mutation. Bioinformatic analysis was carried out to predict the effect of mutation on proteins. Results: A heterozygous mutation (p. R124C) was found in exon 4 of the TGFBI gene in all patients from the pedigree but not among unaffected members. The mode of inheritance of corneal dystrophy in this pedigree was identified as autosomal dominant. Bioinformatics analysis predicted that the p. R124C mutation may be functionally deleterious. The phenotype of corneal dystrophy in the pedigree was determined to be LCD I type. Conclusion: The p. R124C mutation of the TGFBI gene probably underlies the pathogenesis of LCD in this Chinese pedigree. Genetic testing can facilitate proper diagnosis of this type of corneal dystrophy. © 2018 MeDitorial Ltd. All rights reserved.