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鉴定与单基因综合征、复杂疾病和相关特征相关的遗传变异开辟了一条以前没有探索过的途径，即将遗传筛查信息转化为疾病预测工具，通过提高风险及其预测能力，提供更有效的疾病管理。随着时间的推移，揭示这些复杂疾病的遗传学方法不断发展。作为人类基因组计划的一部分，国际HapMap计划成功地提供了人类基因组中超过100万个SNPs(单核苷酸多态性)的信息。SNP基因分型技术发生了一场革命，使数十万个SNP基因分型成为可能，为遗传关联研究开辟了新的领域。HapMap项目还表明，大约50万个snp的基因分型足以覆盖大约75%的常见变异(小等位基因频率>5%)[1]。迄今为止，已发表了大量针对不同疾病的全基因组关联研究(GWAS)[2]。虽然GWAS已经产生了大量的数据，证明了数百个遗传位点与人类复杂特征的关联，但它们不一定能识别出与疾病相关的给定位点上的基因或一组基因，而且它们通常不能给出疾病基因如何功能的更大图景。在许多情况下，最相关的snp仅作为功能变异的标记存在，并且大多数相关区域包含多个基因。迄今为止，GWAS一直基于常见病-常见变异假说，因此未能检测出具有强影响的罕见变异。此外，GWAS的结果在不同人群中并不一致，适用于一个人群的结果不一定适用于另一个人群。 This is due to different mutational mechanisms caused by differences in demographics, cultural histories, food habits, environment etc. which necessitates identifying population-specific variants [3-4]. The next trend that took rise was the next generation platforms (NGS) also known as high-throughput sequencing which had greater yield and advantages over the conventionally used Sanger’s sequencing.

过去十年见证了基因组测序价格的巨大下降，NGS已经成为全自动和高度改进的。目前，完整的基因组可以快速测序，与早期相比，价格也可以负担得起。人类基因组测序每千兆酶的成本比其他物种低得多，这得益于Illumina公司HiSeq X平台[5]等最新测序仪的可用性。NGS可以识别影响遗传表型的遗传变异，包括重要的致病突变和自然变异，不仅可用于医疗领域，还可用于农业和其他社会部门，以改善作物和牲畜。当将NGS作为一个整体考虑时，与全外显子组测序(WES)和靶向基因测序相比，全基因组测序(WGS)可以提供影响表型表达的所有变异的深入知识。但与WES和靶向测序[6]相比，WGS仍然非常昂贵

WES可以简单地解释为测序外显子或基因的蛋白质编码部分的过程，这代表了基因组的功能部分。WES清晰地显示了高外显率等位基因变异及其与疾病表型[7]的关系。由于WES以外显子为目标，并且知道孟德尔或部分孟德尔变异是由非同义、剪接位点和移码变异介导的，因此外显子仍然是筛选部分孟德尔变异的最理想区域。有明确的研究表明，WES导致孟德尔疾病的致病变异的鉴定。据报道，我们所知道的导致孟德尔疾病的大多数突变(80-90%)都发生在外显子区。2011年，科学界惊讶地发现，一名4岁的儿童在对其外显子组进行测序后，最终诊断出了肠道疾病，并从危及生命的疾病中获救。一旦调查人员确定了导致严重症状的基因，就进行了骨髓移植以挽救他的生命。在这种情况下;我们不能使用传统的诊断技术，因为我们需要在正确的时间找到正确的原因。在这个成功的故事之后，我们已经看到WES被非常广泛地用于诊断新综合征和发现已知疾病表型的新突变。 Further, WES was also employed in the diagnosis of young patients who may not show the full spectrum of the disease. WES always had an upper hand over the conventional diagnostic techniques [9-12] with a great influence on what we call a personalized medicine, where even treatment plans are altered based on the genetic profile of an individual. WES also had an advantage of being a totally non-invasive technique that could give confirmed diagnosis compared to other traditional techniques [9,13,14]. The data generated from WES throughout the period from different research groups have also added a numerous number of novel variation/mutations to existing large databases of known SNPs, known pathogenic variants, and control genomes. The Exome Aggregation Consortium (ExAC) has come up with a database exclusively for exome sequences of more than 60,000 unrelated individuals, which is freely available (Exome Aggregation Consortium (ExAC)). Such a database could provide researchers with a large set of reference exomes that they could compare with their novel findings. Now being talked about the advantages of WES till here, it is very much necessary to talk about its limitations too. WES cannot be applied for all the genetic diseases as random because the technology in some cases fails to detect all the genes present even inside a single exon. Exons that are located within repeats sequences and out towards the chromosome tips are again undetected by WES. Structural variations (SVs), which are also an important causative factor for Mendelian disease, are sadly not identified easily by WES. Mitochondrial gene mutations are yet another causative factor that cannot be detected by WES. Triplet repeat disorders, such as Friedreich's ataxia and Huntington’s are undetected by WES radar. Very importantly genes in introns are not detected by WES as they target only exons. The other areas where WES fails are in detecting epigenetic factors, mosaic mutations, uniparental disomy, mutations in repetitive or high GC rich region and mutations in genes with corresponding pseudogenes or other highly homologous sequences. Moreover, WES does not target 100% of the genes in the human genome; approximately 97% of exons are targeted [7].

表1。里程碑式的研究采用WES来寻找致病变异

里程碑式的研究采用WES来寻找致病变异。
疾病名称	参考
肌萎缩性侧索硬化症	约翰逊，J. O.曼德里奥利，M。等人（2010） 神经元68:857-864。
卡波西肉瘤	卞恩，M.， A.阿布扬卡尔，V.。研究出版社（2010） J.实验医学207:2307-2312．
莱伯尔先天性黑蒙	王浩，陈晓霞，陈良。研究出版社（2011） 摩尔，可见，17:3529-3540。
高度近视	史勇，李勇，研究出版社（2011） PLoS Genet, 7: e1002084．
青少年成熟型糖尿病(MODY)	约翰逊，S. H.厄根斯，K. K。研究出版社(2012） PLoS One 7: e38050。
阿尔茨海默病	萨西，C.， R.格雷罗，R研究出版社（2014） 神经生物学老化35:2422.e13-6．
常染色体隐性多囊肾病	徐玉玉，肖波，肖文涛。研究出版社（2014） 基因551:33-38。
肩峰额鼻肌肌张力障碍	史建德，兴安伟，程志明。研究出版社（2014） 点。j . Hum.Genet。95: 235 - 240．
癌症易感性突变	严et .al．（2011）《热内传》43:309-315； 格雷夫et .al．(2012)血120:395-403； 斯内普et .al．（2012）乳腺癌补救治疗．134: 429 - 433； Kiiskiet .al．(2014）Proc。国家的。学会科学。美国111:15172 -15177； 蔡et .al．（2015）Endocr。遗传代数。巨蟹座22:23 - 33。
不明原因的智力残疾和/或发育迟缓	布劳恩，文学博士，舒勒，文学硕士，研究出版社（2016） 肾脏国际， 89(2)， 468-475。

表2．用于WES的主要台式平台

用于WES的主要台式平台
公司	平台/机器名	读取长度
罗氏公司	454 GS初级	400 - 500 bp / 35 mb
Illumina公司	MiSeq	2 × 300bp /15Gb
	MiSeq Dx	2 × 300bp /15Gb
	MiSeq FGx	2 × 300bp /15Gb
	NextSeq 500	2 × 500 bp/120Gb
	NextSeq 550	2 × 500 bp/120Gb
生活的技术	离子质子	200 bp / 10 gb

尽管WES存在所有这些缺点，但在发现一种比WES更好、更快地检测遗传疾病(简单/复杂)的新方法之前，除了使用现有的最佳技术(WES)可以挽救生命并改变治疗计划之外，我们没有任何其他选择或替代方案。通过两个重要的例子，我们讨论了WES的巨大价值，一个是发现了一种罕见疾病背后的已知基因的致病突变，比如普利策奖获奖男孩“尼古拉斯•沃尔克”;[8]和另一个用于识别新基因突变，杜克大学诊所通过使用WES[15]进行快速诊断，挽救了7名儿童中的2名。

鉴定与单基因综合征、复杂疾病和相关特征相关的遗传变异开辟了一条以前没有探索过的途径，即将遗传筛查信息转化为疾病预测工具，通过提高风险及其预测能力，提供更有效的疾病管理。随着时间的推移，揭示这些复杂疾病的遗传学方法不断发展。作为人类基因组计划的一部分，国际HapMap计划成功地提供了人类基因组中超过100万个SNPs(单核苷酸多态性)的信息。SNP基因分型技术发生了一场革命，使数十万个SNP基因分型成为可能，为遗传关联研究开辟了新的领域。HapMap项目还表明，大约50万个snp的基因分型足以覆盖大约75%的常见变异(小等位基因频率>5%)[1]。迄今为止，已发表了大量针对不同疾病的全基因组关联研究(GWAS)[2]。虽然GWAS已经产生了大量的数据，证明了数百个遗传位点与人类复杂特征的关联，但它们不一定能识别出与疾病相关的给定位点上的基因或一组基因，而且它们通常不能给出疾病基因如何功能的更大图景。在许多情况下，最相关的snp仅作为功能变异的标记存在，并且大多数相关区域包含多个基因。迄今为止，GWAS一直基于常见病-常见变异假说，因此未能检测出具有强影响的罕见变异。此外，GWAS的结果在不同人群中并不一致，适用于一个人群的结果不一定适用于另一个人群。 This is due to different mutational mechanisms caused by differences in demographics, cultural histories, food habits, environment etc. which necessitates identifying population-specific variants [3-4]. The next trend that took rise was the next generation platforms (NGS) also known as high-throughput sequencing which had greater yield and advantages over the conventionally used Sanger’s sequencing.

过去十年见证了基因组测序价格的巨大下降，NGS已经成为全自动和高度改进的。目前，完整的基因组可以快速测序，与早期相比，价格也可以负担得起。人类基因组测序每千兆酶的成本比其他物种低得多，这得益于Illumina公司HiSeq X平台[5]等最新测序仪的可用性。NGS可以识别影响遗传表型的遗传变异，包括重要的致病突变和自然变异，不仅可用于医疗领域，还可用于农业和其他社会部门，以改善作物和牲畜。当将NGS作为一个整体考虑时，与全外显子组测序(WES)和靶向基因测序相比，全基因组测序(WGS)可以提供影响表型表达的所有变异的深入知识。但与WES和靶向测序[6]相比，WGS仍然非常昂贵

WES可以简单地解释为测序外显子或基因的蛋白质编码部分的过程，这代表了基因组的功能部分。WES清晰地显示了高外显率等位基因变异及其与疾病表型[7]的关系。由于WES以外显子为目标，并且知道孟德尔或部分孟德尔变异是由非同义、剪接位点和移码变异介导的，因此外显子仍然是筛选部分孟德尔变异的最理想区域。有明确的研究表明，WES导致孟德尔疾病的致病变异的鉴定。据报道，我们所知道的导致孟德尔疾病的大多数突变(80-90%)都发生在外显子区。2011年，科学界惊讶地发现，一名4岁的儿童在对其外显子组进行测序后，最终诊断出了肠道疾病，并从危及生命的疾病中获救。一旦调查人员确定了导致严重症状的基因，就进行了骨髓移植以挽救他的生命。在这种情况下;我们不能使用传统的诊断技术，因为我们需要在正确的时间找到正确的原因。在这个成功的故事之后，我们已经看到WES被非常广泛地用于诊断新综合征和发现已知疾病表型的新突变。 Further, WES was also employed in the diagnosis of young patients who may not show the full spectrum of the disease. WES always had an upper hand over the conventional diagnostic techniques [9-12] with a great influence on what we call a personalized medicine, where even treatment plans are altered based on the genetic profile of an individual. WES also had an advantage of being a totally non-invasive technique that could give confirmed diagnosis compared to other traditional techniques [9,13,14]. The data generated from WES throughout the period from different research groups have also added a numerous number of novel variation/mutations to existing large databases of known SNPs, known pathogenic variants, and control genomes. The Exome Aggregation Consortium (ExAC) has come up with a database exclusively for exome sequences of more than 60,000 unrelated individuals, which is freely available (Exome Aggregation Consortium (ExAC)). Such a database could provide researchers with a large set of reference exomes that they could compare with their novel findings. Now being talked about the advantages of WES till here, it is very much necessary to talk about its limitations too. WES cannot be applied for all the genetic diseases as random because the technology in some cases fails to detect all the genes present even inside a single exon. Exons that are located within repeats sequences and out towards the chromosome tips are again undetected by WES. Structural variations (SVs), which are also an important causative factor for Mendelian disease, are sadly not identified easily by WES. Mitochondrial gene mutations are yet another causative factor that cannot be detected by WES. Triplet repeat disorders, such as Friedreich's ataxia and Huntington’s are undetected by WES radar. Very importantly genes in introns are not detected by WES as they target only exons. The other areas where WES fails are in detecting epigenetic factors, mosaic mutations, uniparental disomy, mutations in repetitive or high GC rich region and mutations in genes with corresponding pseudogenes or other highly homologous sequences. Moreover, WES does not target 100% of the genes in the human genome; approximately 97% of exons are targeted [7].

尽管WES存在所有这些缺点，但在发现一种比WES更好、更快地检测遗传疾病(简单/复杂)的新方法之前，除了使用现有的最佳技术(WES)可以挽救生命并改变治疗计划之外，我们没有任何其他选择或替代方案。通过两个重要的例子，我们讨论了WES的巨大价值，一个是发现了一种罕见疾病背后的已知基因的致病突变，比如普利策奖获奖男孩“尼古拉斯•沃尔克”;[8]和另一个用于识别新基因突变，杜克大学诊所通过使用WES[15]进行快速诊断，挽救了7名儿童中的2名。鉴定与单基因综合征、复杂疾病和相关特征相关的遗传变异开辟了一条以前没有探索过的途径，即将遗传筛查信息转化为疾病预测工具，通过提高风险及其预测能力，提供更有效的疾病管理。随着时间的推移，揭示这些复杂疾病的遗传学方法不断发展。作为人类基因组计划的一部分，国际HapMap计划成功地提供了人类基因组中超过100万个SNPs(单核苷酸多态性)的信息。SNP基因分型技术发生了一场革命，使数十万个SNP基因分型成为可能，为遗传关联研究开辟了新的领域。HapMap项目还表明，大约50万个snp的基因分型足以覆盖大约75%的常见变异(小等位基因频率>5%)[1]。迄今为止，已发表了大量针对不同疾病的全基因组关联研究(GWAS)[2]。虽然GWAS已经产生了大量的数据，证明了数百个遗传位点与人类复杂特征的关联，但它们不一定能识别出与疾病相关的给定位点上的基因或一组基因，而且它们通常不能给出疾病基因如何功能的更大图景。 The most associated SNPs in many cases exist only as a marker for the functional variant and the majority of associated regions contain several genes. So far GWAS have been based on the common disease-common variant hypothesis, thus it has failed to detect rare variants with strong effects. In addition, GWAS findings have been inconsistent across populations and what applies to one population does not necessarily apply to another. This is due to different mutational mechanisms caused by differences in demographics, cultural histories, food habits, environment etc. which necessitates identifying population-specific variants [3-4]. The next trend that took rise was the next generation platforms (NGS) also known as high-throughput sequencing which had greater yield and advantages over the conventionally used Sanger’s sequencing.

过去十年见证了基因组测序价格的巨大下降，NGS已经成为全自动和高度改进的。目前，完整的基因组可以快速测序，与早期相比，价格也可以负担得起。人类基因组测序每千兆酶的成本比其他物种低得多，这得益于Illumina公司HiSeq X平台[5]等最新测序仪的可用性。NGS可以识别影响遗传表型的遗传变异，包括重要的致病突变和自然变异，不仅可用于医疗领域，还可用于农业和其他社会部门，以改善作物和牲畜。当将NGS作为一个整体考虑时，与全外显子组测序(WES)和靶向基因测序相比，全基因组测序(WGS)可以提供影响表型表达的所有变异的深入知识。但与WES和靶向测序[6]相比，WGS仍然非常昂贵

WES可以简单地解释为测序外显子或基因的蛋白质编码部分的过程，这代表了基因组的功能部分。WES清晰地显示了高外显率等位基因变异及其与疾病表型[7]的关系。由于WES以外显子为目标，并且知道孟德尔或部分孟德尔变异是由非同义、剪接位点和移码变异介导的，因此外显子仍然是筛选部分孟德尔变异的最理想区域。有明确的研究表明，WES导致孟德尔疾病的致病变异的鉴定。据报道，我们所知道的导致孟德尔疾病的大多数突变(80-90%)都发生在外显子区。2011年，科学界惊讶地发现，一名4岁的儿童在对其外显子组进行测序后，最终诊断出了肠道疾病，并从危及生命的疾病中获救。一旦调查人员确定了导致严重症状的基因，就进行了骨髓移植以挽救他的生命。在这种情况下;我们不能使用传统的诊断技术，因为我们需要在正确的时间找到正确的原因。在这个成功的故事之后，我们已经看到WES被非常广泛地用于诊断新综合征和发现已知疾病表型的新突变。 Further, WES was also employed in the diagnosis of young patients who may not show the full spectrum of the disease. WES always had an upper hand over the conventional diagnostic techniques [9-12] with a great influence on what we call a personalized medicine, where even treatment plans are altered based on the genetic profile of an individual. WES also had an advantage of being a totally non-invasive technique that could give confirmed diagnosis compared to other traditional techniques [9,13,14]. The data generated from WES throughout the period from different research groups have also added a numerous number of novel variation/mutations to existing large databases of known SNPs, known pathogenic variants, and control genomes. The Exome Aggregation Consortium (ExAC) has come up with a database exclusively for exome sequences of more than 60,000 unrelated individuals, which is freely available (Exome Aggregation Consortium (ExAC)). Such a database could provide researchers with a large set of reference exomes that they could compare with their novel findings. Now being talked about the advantages of WES till here, it is very much necessary to talk about its limitations too. WES cannot be applied for all the genetic diseases as random because the technology in some cases fails to detect all the genes present even inside a single exon. Exons that are located within repeats sequences and out towards the chromosome tips are again undetected by WES. Structural variations (SVs), which are also an important causative factor for Mendelian disease, are sadly not identified easily by WES. Mitochondrial gene mutations are yet another causative factor that cannot be detected by WES. Triplet repeat disorders, such as Friedreich's ataxia and Huntington’s are undetected by WES radar. Very importantly genes in introns are not detected by WES as they target only exons. The other areas where WES fails are in detecting epigenetic factors, mosaic mutations, uniparental disomy, mutations in repetitive or high GC rich region and mutations in genes with corresponding pseudogenes or other highly homologous sequences. Moreover, WES does not target 100% of the genes in the human genome; approximately 97% of exons are targeted [7].

尽管WES存在所有这些缺点，但在发现一种比WES更好、更快地检测遗传疾病(简单/复杂)的新方法之前，除了使用现有的最佳技术(WES)可以挽救生命并改变治疗计划之外，我们没有任何其他选择或替代方案。通过两个重要的例子，我们讨论了WES的巨大价值，一个是发现了一种罕见疾病背后的已知基因的致病突变，比如普利策奖获奖男孩“尼古拉斯•沃尔克”;[8]和另一个用于识别新基因突变，杜克大学诊所通过使用WES[15]进行快速诊断，挽救了7名儿童中的2名。

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3. 王志刚，王志刚，王志刚，等。(1999)印度人线粒体DNA谱系与欧亚西部线粒体DNA谱系的深层共同祖先。当代生物学9: 1331 - 1334。(Crossref)
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