步枪序列组装和最近在人类基因组中的细分重复
Xinwei She1, Zhaoshi Jiang, Royden A Clark
1Department of Genome Sciences, University of Washington School of Medicine, 1705 NE Pacific Street, Seattle, Washington 98195, USA.
Nature
|October 22, 2004
概括
全基因组射击枪 (WGS) 测序努力准确地组装复杂基因组中的大型,高度相似的重复. 这导致了对基因组大小和基因丢失的低估,影响了我们对基因组结构的理解.
科学领域:
- 基因组学就是基因组学.
- 生物信息学是一种生物信息学.
- 进行比较基因组学.
背景情况:
- 复杂的真核生物基因组越来越多地使用全基因组猎枪 (WGS) 方法进行测序.
- WGS 组件因其在解决基因组内的复杂重复结构方面的局限性而面临批评.
研究的目的:
- 量化WGS组装对大,高度相似的细分重复的影响.
- 为了比较两个不同的人类基因组组合中的细分重复内容.
主要方法:
- 两个人类基因组组合的比较分析.
- 量化大 (>15kb) 和高度相同 (>97%) 的重复.
- 在重复区域内分析基因含量.
主要成果:
- WGS组件无法充分解决大型,高度相同的重复.
- 由于未解决的重复,估计的基因组长度显著减少.
- 在这些重复区域内嵌入的基因的损失.
结论:
- 严格的WGS组装过度简化了哺乳动物基因组结构和进化.
- 建议采用混合测序策略,将WGS和克隆逐克隆方法结合起来,以获得准确的重复分辨率.
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