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La selección natural da forma a patrones de polimorfismo de número de copias en todo el genoma en Drosophila
J J Emerson1, Margarida Cardoso-Moreira, Justin O Borevitz
1Department of Ecology and Evolution, University of Chicago, Chicago, IL 60637, USA. jje@uchicago.edu
Science (New York, N.Y.)
|June 7, 2008
Resumen
La selección natural da forma a las mutaciones del número de copias en las moscas de la fruta. La selección purificadora influye fuertemente en las ubicaciones de eliminación, mientras que la selección positiva favorece las duplicaciones en los genes de respuesta a toxinas.
Área de la Ciencia:
- La genómica es la genómica.
- Biología evolutiva Biología evolutiva.
- Genética de la población Genética de la población.
Sus antecedentes:
- La influencia de la selección natural en la evolución de las mutaciones de número de copias no se entiende bien.
- Los polimorfismos de número de copias (CNPs) son una fuente de variación genética con implicaciones evolutivas significativas.
Objetivo del estudio:
- Investigar el papel de la selección natural en la configuración de la distribución genómica y la evolución temprana de las mutaciones de número de copias.
- Para crear un mapa de alta resolución de los CNP en Drosophila melanogaster y analizar su dinámica evolutiva.
Principales métodos:
- Utilizó matrices de tiling de genoma completo de alta densidad para el análisis genómico integral.
- Inferido un gran conjunto de polimorfismos de número de copias independientes (CNPs) en todo el genoma.
Principales resultados:
- Se identificaron 2658 CNP independientes, con un 56% de genes superpuestos.
- Evidencia observada de selección positiva en duplicaciones de alta frecuencia, particularmente aquellas que involucran genes de respuesta a toxinas.
- Demostró que la selección de purificación da forma a las ubicaciones de la CNP, con las deleciones experimentando una selección más fuerte que las duplicaciones.
Conclusiones:
- La selección natural juega un papel crítico en la evolución y la organización genómica de las mutaciones de número de copias.
- La selección purificadora actúa más intensamente en las deleciones que en las duplicaciones, y en las duplicaciones que se superponen en los genes o que se encuentran en el cromosoma X.
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