一例遗传性蛋白C缺陷症家系的实验诊断

目的对1例遗传性蛋白C缺陷症家系进行临床表型诊断和基因突变检测。方法用发色底物法测定血浆蛋白C活性;用聚合酶链反应（PCR）法对先证者PC基因（PROC）的9个外显子及其侧翼序列进行扩增,PCR产物纯化后直接测序,检测其基因突变。家系成员DNA在先证者PROC基因突变区域扩增后测序,进行家系调查以期发现遗传规律。结果先证者蛋白C活性为38.6%,抗原为45.3%。直接基因测序分析发现先证者PROC基因外显子7区存在杂合错义突变c.565C〉T,该突变将引起编码的蛋白C 147位精氨酸被色氨酸替换（p.Arg147Trp）。家系分析发现先证者的c.565C〉T突变遗传于其父亲。结论 c.565C〉T杂合突变是导致该家系遗传性PC缺陷症的原因。     

抗凝血酶基因A9850G突变导致一个新的遗传性抗凝血酶缺陷症家系

目的对一个遗传性抗凝血酶（AT）缺陷症家系进行临床表型诊断和基因突变检测。方法用AT活性（AT：A）和抗原含量（AT：Ag）作实验诊断；用聚合酶链反应（PCR）对先证者AT基因的7个外显子及其侧翼内含子序列进行扩增，PCR产物纯化后直接测序，检测其基因突变（His369Arg），为国际首次报道。结果先证者表现为AT基因外显子5区的第9850位有A—G的杂合突变。结论该突变是遗传性AT缺陷症的一个新的突变位点，可以导致血栓形成。     

凝血因子Ⅹ基因两种新的突变导致的遗传性凝血因子Ⅹ缺陷症

目的　探讨 1个遗传性凝血因子Ⅹ (FⅩ )缺陷症家系的分子发病机制。方法　测定活化部分凝血活酶时间、凝血酶原时间、FⅩ促凝活性以及FⅩ抗原进行表型诊断 ;用PCR方法对先证者的FⅩ基因 8个外显子及其侧翼序列和 5′端非翻译区 (5′UTR)序列进行扩增 ,产物纯化后直接测序检测其基因突变。应用等位基因特异性PCR验证测序所发现的突变。结果　先证者表型诊断为FⅩ缺陷症 (Ⅱ型 ) ;FⅩ基因分析发现 2个杂合突变 :第 1内含子 5′端剪接位点供位GT→AT(IVS1 1G→A)和第 8外显子 1185G→A(Arg347His)。 结论　双重杂合性突变IVS1 1G→A和Arg347His是导致该例遗传性FⅩ缺陷症的原因。     

双重杂合性突变Arg304Glh和Arg304Trp导致的遗传性凝血因子VII缺陷症

目的：探讨一例遗传性凝血因子VII（coagulation factor VII,FVII）缺陷症家系基因突变类型。方法：检测凝血指标以明确诊断；用DNA直接测序法对先证者及其家庭成员FVII基因的全部外显子和其侧翼以及启动子进行分析，寻找基因突变；将含突变序列克隆入pGEMT-easy质粒载体中，对所得两条染色体相应序列分别测序，以确定不同突变在染色体上的分布。应用限制性内切酶MspI对先证者及家系成员相应基因片段进行酶切分析，证实测序所发现的突变。结果：先证者在8号外显子上有两种基因突变：11348位C→T突变和11349C→A突变。pGEMT-easy质粒克隆测序结果显示上述两种突变位于不同的染色体上。为不同染色体同一编码区Arg(CGG)304Trp(TGG)和Arg(CGG)304Gln(CAG)双重杂合性突变。其父亲、母亲分别为11349位G→A和11348位C→T杂合突变；先证者的弟弟FVII基因为正常野生型；其哥哥和3个子女均为杂合性突变。PCR辅助限制性酶切证实了先证者及其家系成员的基因突变。结论：先证者FVII基因突变为不同染色体同一编码区Arg304Trp和Arg304Gln双重杂合性突变，此种突变类型的组合尚属首例。     

抗凝血酶基因A9850G突变导致一个新的遗传性抗凝血酶缺陷症家系

目的对一个遗传性抗凝血酶(AT)缺陷症家系进行临床表型诊断和基因突变检测。方法用AT活性(AT:A)和抗原含量(AT:Ag)作实验诊断;用聚合酶链反应(PCR)对先证者AT基因的7个外显子及其侧翼内含子序列进行扩增,PCR产物纯化后直接测序,检测其基因突变(H is369Arg),为国际首次报道。结果先证者表现为AT基因外显子5区的第9850位有A→G的杂合突变。结论该突变是遗传性AT缺陷症的一个新的突变位点,可以导致血栓形成。     

一个遗传性出血性毛细血管扩张症家系的致病基因研究

目的:通过对一个遗传性出血性毛细血管扩张症家系进行ENG基因和ALK1基因测序,确定基因突变位点。方法:用RT-PCR方法对家系4代11名成员的ENG基因14个外显子和ALK1基因9个外显子进行扩增;扩增产物纯化后直接测序查找基因突变位点。结果:先证者及家系其他患者ENG基因第4外显子存在无义突变c.447G﹥A,导致149位氨基酸Trp(UGG)变为Stop(UGA),在该家系未发现ALK1基因突变。结论:ENG基因无义突变c.G447A引起氨基酸发生p.Trp149Stop改变,是该家系致病的遗传基础。     

遗传性凝血因子Ⅶ缺陷症伴组织因子异常的研究

目的探讨1个遗传性凝血因子Ⅶ（FⅦ）缺陷症伴组织因子异常家系的临床出血机制。方法用DNA直接测序法对先证者FⅦ及组织因子（TF）基因的全部外显子及其侧翼5’和3’非翻译区进行分析，寻找突变基因。反向测序证实所发现的突变。用RT—PCR及筑巢式PCR扩增先证者FⅦ cDNA，检测FⅦ基因大的缺失和（或）插入突变。对其家系成员作突变基因检测。结果在先证者FⅦ基因启动子区检测到-55C→T杂合突变。该突变来自先证者的母亲。其姐姐也带有同样的杂合突变。其他家系成员的FⅦ基因未见突型。在先证者及所有家系成员的TF基因中均发现了9363C—T（Arg131Trp）杂合多态性，9363T基因杂合频率为2．63％。结论首次报道先证者的临床出血与FⅦ杂合突变及TF的杂合多态性有关。     

抗凝血酶基因杂合突变导致的抗凝血酶缺陷症

目的 对1例先天性抗凝血酶（AT）缺陷症患者及其家系成员进行AT表型及基因突变检测。方法 采用发色底物法和免疫比浊法分别检测先证者及其家系成员血浆AT活性（AT：A）和AT抗原含量（AT：Ag），并采用PCR法对先证者AT基因的7个外显子及其侧翼内含子序列进行扩增，PCR产物纯化后直接测序检测基因突变。结果 先证者的AT：Ag正常，但AT：A为正常值的65％，表现为Ⅱ型AT缺陷，其AT基因外显子6区第13830位核苷酸发生了G—A杂合突变，引起Arg393His错义突变。同样突变也见于该家系其他3名成员。结论 该家系成员的Ⅱ型AT缺陷由AT基因G13830A杂合突变所致，可致血栓形成。     

凝血因子Χ基因两种新的突变导致的遗传性凝血因子Χ缺陷症

目的:探讨1个遗传性凝血因子Χ(FΧ)缺陷症家系的分子发病机制。方法：测定活化部分凝血活酶时间、凝血酶原时间、FΧ促凝活性以及FΧ抗原进行表型诊断；用PCR方法对先证的FΧ基因8个外显子及其侧翼序列和5′端非翻译区(5′UTR)序列进行扩增，产物纯化后直接测序检测其基因突变。应用等位基因特异性PCR验证测序所发现的突变。结果：先证表型诊断为FΧ缺陷症(Ⅱ型)；FΧ基因分析发现2个杂合突变：第1内含子5′端剪接位点供位GT→AT(IVS1 1G′A)和第8外显子1185G′A(Arg347His)。结论：双重杂合性突变IVS1 1G′A和Arg347His是导致该例遗传性FΧ缺陷症的原因。     

两个遗传性凝血因子Ⅶ缺乏症家系分子缺陷的初步探讨

目的：探讨两个遗传性凝血因子Ⅶ（FⅦ）缺乏症家系的基因突变类型。方法：用DNA直接测序法对2例患者及其家庭成员FⅦ基因进行分析；应用等位基因特异PCR（ASPCR）以及PCR辅助酶切反应鉴定是否有基因改变。结果：家系A中先证者有两种基因突变：6390位T→G导致Trp40Cys,11496位G→A导致Arg353Gln，这两个突变均为杂合子；PCR辅助MspⅠ酶切证实其母亲也是杂合子Arg353Gln。家系B的先证者有11482T→G，导致His348Gln,PCR辅助NspⅠ酶切证实称证者及其女含有同样的杂保子基因突变，不安现有11514位C→T导致Thr359Met,ASPCR证实先证者及其子携带同样的杂合子突变基因。结论：在两个遗传性FⅦ缺乏症家系中找到3种FⅦ基因的错义突变，其中Trp40Cys为首次报道。     

遗传性蛋白S缺陷症家系基因突变的研究

目的 对2个遗传性PS缺陷症家系进行临床表型诊断和基因突变检测.方法 PS:A测定采用发色底物法;TPS:Ag、FPS;Ag测定采用ELISA法;PS基因(PROS1基因)检测采用PCR方法 对先证者PROS1基因的15个外显子及其侧翼内含子序列进行扩增,PCR产物纯化后直接测序.结果 先证者1的PS:A为48.6%,FPS:Ag为41 mg/L,TPS:Ag为136 mg/L,PROS1基因2号外显子在c.C121T位点发生杂合碱基替换,导致编码的PS蛋白存在Arg-1 Cys(R-1C)杂合错义突变.先证者2的PS:A为29.2%,FPS;Ag为26 mg/L,TPS:Ag为83 mg/L,PROSl基因14号外显子在c.C1687T位点发生杂合碱基替换,导致编码的PS蛋白存在Gln522Stop杂合无义突变.结论 c.C121T是PROS1基因的一个新的突变位点,该杂合突变可以导致Ⅱ型遗传性PS缺陷症;c.C1687T杂合突变导致Ⅰ型遗传性PS缺陷症.     

Seven novel mutations in the factor XIII A-subunit gene causing hereditary factor XIII deficiency in 10 unrelated families.

BACKGROUND: Hereditary factor (F)XIII deficiency is a rare bleeding disorder mostly due to mutations in FXIII A subunit. OBJECTIVES: We studied the molecular basis of FXIII deficiency in patients from 10 unrelated families originating from Israel, India and Tunisia. METHODS: Exons 2-15 of genomic DNA consisting of coding regions and intron/exon boundaries were amplified and sequenced. Structural analysis of the mutations was undertaken by computer modeling. RESULTS: Seven novel mutations were identified in the FXIIIA gene. The propositus from the Ethiopian-Jewish family was found to be a compound heterozygote for two novel mutations: a 10-bp deletion in exon 12 at nucleotides 1652-1661 (followed by 22 altered amino acids and termination codon) and Ala318Val mutation. The propositus of the Tunisian family was homozygous for C insertion after nucleotide 863 within a stretch of six cytosines of exon 7. This insertion results in generation of eight altered amino acids followed by a termination codon downstream. The propositus from Indian-Jewish origin was found to be homozygous for G to T substitution at IVS 11 [+1] resulting in skipping of exons 10 and 11. In addition to the Ala318Val mutation, three of the novel mutations identified are missense mutations: Arg260Leu, Thr398Asn and Gly210Arg each occurring in a homozygous state in an Israeli-Arab and two Indian families, respectively. CONCLUSIONS: Structure-function correlation analysis by computer modeling of the new missense mutations predicted that Gly210Arg will cause protein misfolding, Ala318Val and Thr398Asn will interfere with the catalytic process or protein stability, and Arg260Leu will impair dimerization.     

一种新的抗凝血酶基因突变导致遗传性抗凝血酶缺陷症

目的对1例遗传性抗凝血酶（AT）缺陷症患者及其家系成员AT活性（AT：A）、AT抗原含量（AT：Ag）进行检测及基因分析，探讨该遗传性AT缺陷症发病的分子机制。方法采用发色底物法和免疫比浊法分别检测先证者及其家系成员血浆AT：A和AT：Ag，提取外周血基因组DNA，PCR法扩增AT基因的全部7个外显子及侧翼序列，DNA序列分析AT的基因异常。结果先证者AT：A和AT：Ag分别为45％和97mg／L，为Ⅰ型AT缺陷症。AT基因外显子5区第9833位核苷酸发生杂合性T→A突变，引起Tyr363Stop（Y363X）无义突变。其他家系成员基因测序结果显示有4人（Ⅱ2、Ⅱ6、Ⅲ7、Ⅲ14）存在该突变。结论该家系为I型遗传性AT缺陷症。AT基因外显子5区杂合性9833T—A无义突变引起AT缺陷，导致静脉血栓是该遗传性AT缺陷症的分子致病机制。该突变在国际上尚未见报道。     

一个遗传性凝血因子Ⅶ缺陷症家系两种新的基因突变

目的 探讨遗传性凝血因子Ⅶ(FⅦ)缺陷症的分子发病机制.方法 用DNA直接测序法对1例FⅦ缺陷症家系成员FⅦ基因进行分析;将含突变序列克隆插入pMD19-T Simple TA载体中,对所得两条染色体相应序列分别测序,以确定不同突变在染色体上的分布.采用酶联免疫吸附试验(ELISA)和凝固法检测血浆中FⅦ:Ag和FⅦ:C.结果 家系中有3种基因突变:第8号外显子第15386位核苷酸存在A→C(Arg353Pro)和第15386位核苷酸G→C(Gln353Pro)突变;第8号外显子第15274位核苷酸A→T(Lys316Stop)突变,家系成员中发现的这3种突变均为杂合子;发现先证者父亲存在3种杂合多态性:即启动子区2050～2059位CCTATACCT 10 bp的缺失/插入多态性、1号内含子IVS1a+9 G→A及第15386位A→G(Arg353Gln),且均来自先证者祖父,3种多态性位于同一条染色体上.结论 发现该家系存在1种FⅦ基因的错义突变(Gln353Pro);1种无义突变(Lys316Stop),这两种突变均为国际上首次报道的新突变.

Abstract：

Objective To explore the mutations of coagulation factor Ⅶ ( F Ⅶ ) gene in one pedigree with hereditary F Ⅶ deficiency, and to investigate the molecular mechanisms of F Ⅶdeficiency. Methods FⅦ gene mutations were analysed in the pedigree by direct DNA sequencing. The mutated DNA fragments were cloned into pMD19-T simple TA vector, and sequenced to confirm their distribution on chromosome. The plasma activity of F Ⅶ of the probands and their family members was detected with coagulation assay. The antigen of F Ⅶ were identified with ELISA. Results Three gene mutations were detected in the pedigree: A/G to C at 15386 resulting in Arg353Pro/Gln353Pro, A to T at 15274 resulting in Lys316Stop, all three mutations were heterozygotes. Three kinds of polymorphisms were identified in his father: A to G transition at position 15386 resulting in Arg353Gln, heterozygotic deletion of 2050 -2059 cctatatcct in promoter and G to A mutation in intron 1a, the same polymorphisms were found in his grandfather. The three polymorphisms were located in the same chromosome of his father. Conclusion Two mutations were found in the pedigree with hereditary FⅦ deficiency. One is nonsense mutation( Lys316Stop), the other is missense one(Gln353Pro).Gln353Pro and Lys316Stop might be the molecular mechanisms of FⅦ deficiency. The two novel mutations were reported for the first time in the literature.     

Mutation analysis in Spanish patients with hereditary hemorrhagic telangiectasia: deficient endoglin up-regulation in activated monocytes

BACKGROUND: Mutations in the endoglin (ENG) or ALK1 genes are responsible for hereditary hemorrhagic telangiectasia types 1 and 2 (HHT1 and HHT2), respectively, a dominant vascular dysplasia caused by haploinsufficiency. No formal mutation studies of patients with HHT have been conducted in Spain. METHODS: ENG and ALK1 mutation analyses were carried out in 13 Spanish HHT patients diagnosed according to the Curacao criteria. Because endoglin is up-regulated at the cell surface during the monocyte-macrophage transition, endoglin concentrations in activated monocytes were determined by immunofluorescence flow cytometry in a systematic analysis. As controls, 40 non-HHT volunteers were studied for up-regulation of endoglin in activated monocytes. RESULTS: The mutation responsible for HHT was identified in eight patients belonging to two unrelated families. One of the families has a nonsense mutation in exon 4 (c.511C>T; R171X) of the ENG gene, and accordingly the disorder was identified as HHT1. The other family has a missense mutation affecting exon 8 (c.1120C>T; R374W) of the ALK1 gene, and hence is a HHT2 family. Interestingly, endoglin up-regulation was deficient in activated monocytes of both HHT1 and HHT2 patients compared with controls. By contrast, endoglin up-regulation was age-independent in control donors across a broad range of ages. The extent of endoglin up-regulation in activated monocytes was most diminished in those patients with the most severe symptoms. CONCLUSIONS: Endoglin up-regulation in activated monocytes is impaired in HHT1 and HHT2 patients and is age-dependent in both HHT types. Endoglin expression may predict the clinical severity of HHT.