巴比二氏综合症家系致病基因的筛

发布时间：2018-10-05 18:06

【摘要】： 目的:对中国汉族2个巴比二氏综合症(Bardet Biedl Syndrome,BBS)遗传性疾病家系进行遗传连锁分析及基因测序,筛选鉴定新致病基因位点和/或新致病基因及鉴定已知基因的新突变,以确认致病基因并阐明致病机理。方法:1.采集中国汉族2个巴比二氏综合症遗传性疾病家系的临床资料和血样标本,提取血样标本中DNA,建立病人的临床信息数据库。2.针对巴比二氏综合症遗传性疾病的已知基因,设计引物进行测序,排除或定位于已知基因。应用遗传连锁方法,选择已知位点及已知基因物理位置附近的STR(short tandom repeat markers)标记物进行已知基因及已知位点的筛查。3.对是已知位点和基因的家系的阳性位点附近有连锁的,在其附近进行进一步的遗传间距更近的遗传连锁分析;对排除已知位点及基因的家系,用382个STR标记物(ABI PRISM Linkage Mapping Sets V2.5-MD ),PCR扩增其片段,采用ABI3100遗传分析仪进行全基因组的扫描。4.用国际公认的遗传连锁分析方法,根据等位基因(单倍体)分型结果,应用两点法,分别计算STR标记物的LOD值(Lod Score值,表明疾病基因与该位点连锁的紧密性大小),以最大LOD值确定阳性位点。5.在阳性位点附近,根据荧光标记的STR(single nucleotide polymophism)基因型检测结果,进行更精细定位,确定疾病基因的最小遗传间距MGI(Minimum Genetic Interval)。在MGI内,通过候选基因法筛选其致病基因及突变。结果:1.建立了中国汉族巴比二氏综合症遗传性疾病家系的临床及临床信息数据库。2.完成了对1个巴比二氏综合症(Bardet-Biedl Syndrome, BBS)疾病家系是已知基因BBS7的连锁定位和测序,发现其是已知基因的新突变,为BBS致病机制的进一步阐明提供了依据。3.完成对1个BBS遗传性疾病家系是已知基因BBS5的连锁定位,测序工作目前正在进行中。4.本课题研究的结论,对于该领域的研究具有重要的学术价值,为以后的基因筛查、基因诊断和基因治疗都起到了很大的作用。结论:1.我们收集了2个中国汉族巴比二氏综合症遗传性疾病家系的临床资料,丰富了神经系统遗传性疾病的遗传资源信息。2.发现了中国汉族1个已知基因BBS7的新突变。
[Abstract]:Objective: to study the genetic linkage analysis and gene sequencing of two families with Bardet Biedl Syndrome,BBS in Chinese Han nationality, and to identify new pathogenic gene loci and / or new pathogenicity genes and identify new mutations of known genes. In order to identify the pathogenic gene and clarify the pathogenesis. Method 1: 1. The clinical data and blood samples of 2 families with Barbiz syndrome in Chinese Han nationality were collected and DNA, was extracted from the blood samples to establish the clinical information database of patients. A primer was designed to sequence the known genes of Barbiz syndrome and to exclude or localize the known genes. Genetic linkage method was used to screen known genes and known loci by selecting STR (short tandom repeat markers) markers near known sites and physical locations of known genes. If there is a linkage near the positive locus of a family with known loci and genes, further genetic linkage analysis closer to the genetic distance is carried out; for families excluding known loci and genes, The fragments were amplified by using 382 STR markers (ABI PRISM Linkage Mapping Sets V2.5-MD), and the whole genome was scanned by ABI3100 genetic analyzer. According to the results of allelic (haploid) genotyping, the LOD (Lod Score values of STR markers were calculated by using the internationally recognized genetic linkage analysis method. This indicates that the disease gene is closely linked to the locus) and the maximum LOD value is used to determine the positive locus. In the vicinity of the positive loci, according to the results of STR (single nucleotide polymophism) genotypes detected with fluorescent markers, more precise mapping was carried out to determine the minimum genetic spacing of disease genes MGI (Minimum Genetic Interval). In MGI, the pathogenic genes and mutations were screened by candidate gene method. The result is 1: 1. The clinical and clinical information database. 2. 2. The linkage mapping and sequencing of a known gene BBS7 in a family of Bardet-Biedl Syndrome, BBS) disease was completed. It was found that it was a new mutation of known gene, which provided a basis for further elucidation of the pathogenesis of BBS. A pedigree with BBS hereditary diseases was linked to a known gene, BBS5, and the sequencing work was under way. 4. 4. The conclusion of this research has important academic value for the research in this field, and plays a great role in gene screening, gene diagnosis and gene therapy in the future. Conclusion 1. We collected the clinical data of 2 families with Barbiz syndrome in Chinese Han nationality, which enriched the genetic resource information of genetic diseases of the nervous system. A new mutation of a known gene BBS7 was found in Chinese Han nationality.
【学位授予单位】：重庆医科大学
【学位级别】：硕士
【学位授予年份】：2008
【分类号】：R394.112

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