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An Allele-specific Gene Expression Assay to Test the Functional Basis of Genetic Associations
Published on: November 3, 2010
Inferir divergencias antiguas requiere genes con fuertes señales filogenéticas
Leonidas Salichos1, Antonis Rokas
1Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee 37235, USA.
Nature
|May 10, 2013
Resumen
El análisis filogenómico revela incongruencia en el árbol genético, desafiando los métodos estándar. La selección de genes con alto apoyo filogenético es crucial para reconstruir con precisión la historia evolutiva.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- La genómica es la genómica.
- La bioinformática es la bioinformática.
Sus antecedentes:
- Los estudios filogenómicos a menudo se enfrentan a conflictos topológicos (incongruencia) entre los árboles genéticos.
- Los métodos actuales como la concatenación y la eliminación de taxones deshonestos intentan mitigar la incongruencia.
- La fiabilidad de la inferencia filogenética depende de abordar la discordancia del árbol genético.
Objetivo del estudio:
- Investigar el impacto de la incongruencia en los análisis filogenómicos.
- Evaluar la eficacia de las prácticas comunes para resolver las incongruencias.
- Identificar estrategias óptimas para una reconstrucción filogenética robusta.
Principales métodos:
- Análisis filogenómico de 1.070 ortólogos de 23 genomas de levaduras.
- Árboles genéticos individuales inferidos y una filogenia concatenada.
- Evaluación de la gravedad de la incongruencia y el impacto de los criterios de selección de genes/internodos.
Principales resultados:
- Se identificaron 1.070 árboles genéticos incongruentes, en conflicto con la filogenia concatenada.
- La incongruencia aumentó con los internodos más cortos más profundos en la filogenia.
- El soporte de internodos promedio alto mejora significativamente la robustez de la inferencia filogenética.
Conclusiones:
- Las prácticas estándar como la concatenación pueden no ser suficientes para una reconstrucción precisa de divergencias antiguas.
- Es esencial seleccionar genes con fuertes señales filogenéticas.
- Demostrar la ausencia de incongruencia significativa mejora la precisión filogenética.
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