通过全外因组测序揭示的新突变与自闭症有很强的关联
Stephan J Sanders1, Michael T Murtha, Abha R Gupta
1Program on Neurogenetics, Child Study Center, Department of Psychiatry, Yale University School of Medicine, 230 South Frontage Road, New Haven, Connecticut 06520, USA.
Nature
|April 13, 2012
概括
大脑表达基因的罕见de novo突变显著增加自闭症谱系障碍 (ASD) 的风险. 在同一基因中识别多个de novo单核酸变异可靠地确定自闭症风险等位基因.
科学领域:
- 遗传学 是一个遗传学.
- 神经科学是一个神经科学.
- 发育生物学 发展生物学
背景情况:
- 罕见的de novo拷贝数变化已成为自闭症谱系障碍 (ASD) 风险因素.
- 单核酸变体 (SNV) 在自闭症风险中的作用需要进一步澄清,特别是它们在对照中的频率.
- 在未受影响的个体中对新编码突变的表征对于解释ASD患者的发现至关重要.
研究的目的:
- 调查单核酸变体对自闭症谱系障碍 (ASD) 风险的贡献.
- 描述大脑表达基因中新突变的频率和分布.
- 建立一种方法来识别新的ASD风险基因,使用对照中的突变率.
主要方法:
- 对928个个体进行了全外体序列测序,其中包括200个表型不一致的兄弟姐妹对.
- 分析的重点是大脑表达的基因中的高度破坏性的de novo突变 (无意义和拼接部位).
- 在未受影响的个体中使用突变率来确定统计学上显著的风险等位基因.
主要成果:
- 大脑表达基因中的高度破坏性的de novo突变与自闭症谱系障碍 (ASD) 有显著的关联,并且具有很大的影响大小.
- 在无关的试剂中,同一基因中的多个独立的de novoSNV可以作为风险等位基因的可靠指标.
- 在SCN2A基因中观察到两种独立无意义变异的罕见实例在试验者中,但不是对照者,这是一个统计学上不太可能的事件.
结论:
- 新的一种单核酸变异,特别是大脑表达基因中的破坏性变异,代表了自闭症谱系障碍 (ASD) 的重要遗传风险因素.
- 基于对照中的突变率来识别风险等位基因的开发方法为发现新的ASD相关基因提供了强大的方法.
- 对SCN2A等特定基因的进一步研究可能会阐明与ASD相关的关键神经发育途径.
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