全エクソーム配列解析によって明らかになったデノボ変異は,自閉症と強く関連しています
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
まとめ
脳で発現する遺伝子の珍しいde novo変異は,自閉症スペクトル障害 (ASD) のリスクを大幅に増加させます. 同じ遺伝子の複数のデノボ単一のヌクレオチド変異を特定することで,自閉症のリスクアレルを確実に特定できます.
科学分野:
- 遺伝学 遺伝学とは
- 神経科学は神経科学である.
- 発達生物学 発達生物学について
背景:
- 稀な de novo コピー数変異は,自閉症スペクトル障害 (ASD) のリスク要因として確立されています.
- ASDリスクにおけるde novo単一の核酸変種 (SNVs) の役割については,特にコントロールにおけるその頻度については,さらなる明確化が必要である.
- 影響を受けていない個体におけるデノボコード変異の特徴づけは,ASD患者の発見の解釈に不可欠です.
研究 の 目的:
- 自閉症スペクトル障害 (ASD) リスクに対するデノボの単一核性子変異の貢献を調査する.
- 脳で発現する遺伝子のデノボ変異の頻度と分布を特徴づける.
- コントロールの変異率を使用して,新しいASDリスク遺伝子を特定するための方法を確立する.
主な方法:
- 全エクソームシーケンシングは,200のフェノタイプ的に不一致する兄弟のペアを含む928人の個体で行われました.
- 分析は,脳で発現する遺伝子の非常に破壊的なde novo変異 (ナンセンスとスプライスサイト) に焦点を当てた.
- 影響を受けていない個体における変異率は,統計的に有意なリスクアレルを特定するために使用されました.
主要な成果:
- 脳で発現する遺伝子の非常に破壊的なde novo変異は,自閉症スペクトラム障害 (ASD) と有意に関連しており,大きな効果サイズを持っています.
- 無関係なプロバンドの間で同じ遺伝子内の複数の独立したde novoSNVは,リスクアレルの信頼できる指標として機能します.
- SCN2A遺伝子の2つの独立したナンセンス変異の希少な例は,プロバンドでは観察されたが,コントロールでは観察されなかった.
結論:
- De novo単一の核酸変種,特に脳発現遺伝子の破壊的なものは,自閉症スペクトル障害 (ASD) の重要な遺伝的危険因子です.
- 制御における変異率に基づいてリスクアレルを特定する開発された方法は,ASDに関連した新しい遺伝子を発見するための堅実なアプローチを提供します.
- SCN2Aのような特定の遺伝子に関するさらなる研究は,ASDに関与する重要な神経発達経路を解明する可能性があります.
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