脆弱なXのDNA不安定性をトリヌクレオチド重複配列p(CCG) nにマッピングする
E J Kremer1, M Pritchard, M Lynch
1Department of Cytogenetics and Molecular Genetics, Adelaide Children's Hospital, South Australia.
Science (New York, N.Y.)
|June 21, 1991
まとめ
脆弱なX症候群の血統の不安定性は,特定のトリヌクレオチドの繰り返し配列と関連しています. この複製コピーの数の変動は,脆弱なサイトと観察された遺伝的不安定性を説明する可能性があります.
科学分野:
- 遺伝学 遺伝学とは
- 分子生物学は分子生物学である.
- 人間の病気 ヒトの病気
背景:
- 脆弱X症候群は,X染色体上の脆弱な部位に関連した遺伝疾患です.
- 以前の研究では,脆弱なX症候群の系統内の特定のDNA領域の不安定性が示されました.
研究 の 目的:
- 脆弱X症候群の不安定性を示す制限断片のDNA配列を決定する.
- 不安定の領域を特定し,その分子基盤を調査する.
主な方法:
- Pst Iの制限断片のDNAシーケンシング.
- 正常および罹患した個体における側面配列の分析.
- ソマティック細胞ハイブリッドにおけるブレイクポイントのマッピング.
- クローニングとポリメラーゼ連鎖反応 (PCR) 増幅による再現領域の増幅.
主要な成果:
- この不安定性は,トリヌクレオチドの繰り返し配列,p(CCG) n.に局限していた.
- 繰り返しを横切るシーケンスが,正常な個体と罹患した個体間で保存された.
- ソマティック細胞のハイブリッドのブレイクポイントは,繰り返しの領域にマッピングされています.
- 複製は,クローンとPCR増幅の間,in vitroで不安定であることが示されました.
結論:
- トリヌクレオチド重複の複製数の変動が,不安定性の分子基盤として提案されています.
- この繰り返しコピー数の変動は,脆弱なX症候群で観察された脆弱な部位を説明する可能性があります.
- この発見は,不安定な領域の in vivo および in vitro 特性に対する分子的な説明を提供します.
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