《分子诊断学概论 精品文档》由会员分享，可在线阅读，更多相关《分子诊断学概论 精品文档（36页珍藏版）》请在金锄头文库上搜索。
1、分子診斷學概論,第一章 綜說 overview 疾病發生原因的影響層次 DNA、RNA或蛋白質 分子診斷的目的 偵測這些致病因子是那個層次發生變化 本書著重DNA、RNA的變化 蛋白質層次由原文書章節提供 The Application of Proteomics To Disease Diagnostics,遺傳分子的基礎 生物巨分子：DNA、RNA、蛋白質、糖類、脂質 遺傳物質DNA的發現 1928 格里夫茲 (Griffith)肺炎雙球菌轉形試驗 1942 艾佛瑞(Avery)研究格里夫茲轉形的物質為何? 1952 赫希-卻斯 (Hershey-Chase)以放射線標示噬菌體的蛋白質（S
2、35）和DNA（P32），感染大腸桿菌的實驗 1953 雙螺旋結構的發現 2003 人類基因體計畫的完成,參考資料：http:/fig.cox.miami.edu/cmallery/150/gene/sf11x1b.jpg,參考資料：http:/fig.cox.miami.edu/cmallery/150/gene/sf11x1b.jpg,www.accessexcellence.org,參考資料：http:/biotech.nstm.gov.tw/advance/a021.asp,Presented here is a genome sequence of an individual hum
3、an. It was produced from 32 million random DNA fragments, sequenced by Sanger dideoxy technology and assembled into 4,528 scaffolds, comprising 2,810 million bases (Mb) of contiguous sequence with approximately 7.5-fold coverage for any given region. We developed a modified version of the Celera ass
4、embler to facilitate the identification and comparison of alternate alleles within this individual diploid genome. Comparison of this genome and the National Center for Biotechnology Information human reference assembly revealed,more than 4.1 million DNA variants, encompassing 12.3 Mb. These variant
5、s (of which 1,288,319 were novel) included 3,213,401 single nucleotide polymorphisms (SNPs), 53,823 block substitutions (2206 bp), 292,102 heterozygous insertion/deletion events (indels)(1571 bp), 559,473 homozygous indels (182,711 bp), 90 inversions, as well as numerous segmental duplications and c
6、opy number variation regions. Non-SNP DNA variation accounts for 22% of all events identified in the donor, however they involve 74% of all variant bases. This suggests an important role for non-SNP genetic alterations in defining the diploid genome structure. Moreover, 44% of genes were heterozygou
7、s for one or more variants. Using a novel haplotype assembly strategy, we were able to span 1.5 Gb of genome sequence in segments .200 kb, providing further precision to the diploid nature of the genome. These data depict a definitive molecular portrait of a diploid human genome that provides a star
8、ting point for future genome comparisons and enables an era of individualized genomic information.,Author Summary We have generated an independently assembled diploid human genomic DNA sequence from both chromosomes of a single individual (J. Craig Venter). Our approach, based on whole-genome shotgu
9、n sequencing and using enhanced genome assembly strategies and software, generated an assembled genome over half of which is represented in large diploid segments (.200 kilobases), enabling study of the diploid genome. Comparison with previous reference human genome sequences, which were composites
10、comprising multiple humans, revealed that the majority of genomic alterations are the well-studied class of variants based on single nucleotides (SNPs). However, the results also reveal that lesserstudied genomic variants, insertions and deletions, while comprising a minority (22%) of genomic variat
11、ion events, actually account for almost 74% of variant nucleotides. Inclusion of insertion and deletion genetic variation into our estimates of interchromosomal difference reveals that only 99.5% similarity exists between the two chromosomal copies of an individual and that genetic variation between
12、 two individuals is as much as five times higher than previously estimated. The existence of a well-characterized diploid human genome sequence provides a starting point for future individual genome comparisons and enables the emerging era of individualized genomic information.,Identification and an
13、alysis of functional elements in 1% of the human genome by the ENCODE pilot project. Nature. 2007 Jun 14;447(7146):799-816,The Encyclopedia of DNA Elements (ENCODE) Project provide a more biologically informative representation of the human genome by using high-throughput methods to identify and cat
14、alogue the functional elements encoded.,First, our studies provide convincing evidence that the genome is pervasively transcribed, such that the majority of its bases can be found in primary transcripts, including non-protein-coding transcripts, and those that extensively overlap one another. Second
15、, systematic examination of transcriptional regulation has yielded new understanding about transcription start sites, including their relationship to specific regulatory sequences and features of chromatin accessibility and histone modification. Third, a more sophisticated view of chromatin structur
16、e has emerged, including its inter-relationship with DNA replication and transcriptional regulation. Finally, integration of these new sources of information, in particular with respect to mammalian evolution based on inter- and intra-species sequence comparisons, has yielded new mechanistic and evolutionary insights concerning the functional landscape of the human genome. Together, these studies are defining a path for pursuit of a more comprehensive characterization of human genome function.,
