摘要
目的 分析和确定遗传性出血性毛细血管扩张症 (HHT)的临床表型。寻找鉴定HHT家系致病基因ALK1基因突变位点 ,建立HHT的基因诊断方法。方法 用鼻内镜直视并动态摄影观察先证者鼻腔黏膜扩张的毛细血管 ,并进行遗传史的家系调查 ;用聚合酶链反应 (PCR)扩增先证者ALK1基因 3、7、8号外显子 ,并进行PCR产物核苷酸测序。确定突变位点后 ,扩增 2例正常人及HHT家系成员 (4例 )的对应基因区域并行核苷酸序列分析。用Western印迹技术对先证者及家系成员血浆中凝血酶调节蛋白 (TM)进行检测 ,并对Western印迹结果进行灰度扫描 ,以半定量TM水平。结果该家系 5名成员中 ,除无血缘关系的先证者弟媳外 ,其余 4例均有不同程度的鼻出血或其他部位出血史 ;先证者及其父亲分别有明显的鼻黏膜或手指皮肤的毛细血管扩张 ;基因筛查结果显示 :先证者 ,先证者弟弟及其父亲均在ALK1基因 8号外显子第 12 31位核苷酸存在C→T突变 (CGG→TGG) ,而先证者弟媳和侄儿未检测到 12 31位核苷酸的C→T变异 ,正常人不存在该位点的核苷酸变异。Western印迹技术分析血浆TM表达显示分子量在 5 6 0 0 0处 ,2例正常对照 ,与 3例HHT患者灰度扫描平均值分别为 2 18.3和 174 1;在 2 80 0 0处 ,2例正常对照 ,与 3例HHT患者灰度扫描平均值分别为 2
Objective To analysis and define the clinical phenotype and related mutation of hereditary hemorrhagic telangiectasia. (HHT). Methods The proband of a Chinese HHT family, female, aged 48, and 2 of her family members: her father, aged 74, and her brother, aged 44 underwent nasal cavity endoscopy and automatic photochonography to observe the capillaries in nasal mucosa. Samples of peripheral blood were collected. The exons 3, 7, and 8 of the activin receptor-like kinase 1(ALK1) gene of the proband and her family members and 2 healthy people as contrds were amplified by polymerase chain reaction, and the PCR products were sequenced. The levels of plasma thrombomodulin (TM) of the proband and her family members were detected by Western blotting combined with density screening. Results Except the mother and sister-in-law, other 4 of the family members had epistaxis or bleeding in other sites. The proband and her father had obvious telangiectasis of nasal mucosa or finger skin respectively. ALK1 gene analysis confirmed that a C1231T mutation (CGG→TGG) in the exon 8 existed in the proband, her brother, and her father, no mutation was found in her sister in law, her nephew, and the healthy persons. Six bands were shown in the expression of plasma thrombomodulin. Density screening was conducted for the 2 bands with differential expression: those with the molecular masses of 56 000 and 28 000. The result of density screening showed that the average value of screening at the 56 000 band was 218.3 in the normal controls, significantly higher than that of the HTT patients (145.1); and the average value of screening at the 28 000 band was 222.0 in the normal controls, significantly higher than that in the HTT patients (145.1). Conclusion ALK1 gene mutation, a C1231T variation on exon 8, exists in Chinese type 2 HHT individuals. The levels of plasma thrombomodulin levels at the 56 000 and 28 000 fragments of the HTT patients are lower than of normal subjects whose significance and mechanism remain to be elucidated.
出处
《中华医学杂志》
CAS
CSCD
北大核心
2004年第3期182-185,共4页
National Medical Journal of China
基金
国家自然科学基金重点资助项目 (3 983 0 180 )
