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La secuenciación de ADN de paso bajo de 1200 sardos reconstruye la filogenia del cromosoma Y europeo
Paolo Francalacci1, Laura Morelli, Andrea Angius
1Dipartimento di Scienze della Natura e del Territorio, Università di Sassari, Sassari, Italy. pfrancalacci@uniss.it
Science (New York, N.Y.)
|August 3, 2013
Resumen
El análisis genético de los machos sardos revela nuevas variaciones del cromosoma Y, mejorando nuestra comprensión de los orígenes de la población. Este estudio detalla linajes sardos únicos y sus antiguas conexiones con la historia genética humana más amplia.
Área de la Ciencia:
- Genética de la población Genética de la población.
- Estudios de la Evolución Humana Estudios de la Evolución Humana
- Análisis del cromosoma Y.
Sus antecedentes:
- La porción específica masculina del cromosoma Y (MSY) es crucial para rastrear los orígenes de la población humana.
- Los estudios previos sobre la variación genética de MSY estaban limitados por datos genéticos incompletos.
- La historia demográfica única de Cerdeña la convierte en una ubicación ideal para estudios genéticos de poblaciones.
Objetivo del estudio:
- Analizar exhaustivamente la variación genética dentro del cromosoma Y masculino sardo (MSY).
- Para reconstruir un detallado árbol filogenético MSY que incorpore linajes específicos de Cerdeña.
- Para calibrar el árbol filogenético con datos arqueológicos para estimar el tiempo de expansión de la población.
Principales métodos:
- Secuenciación del genoma completo de 1204 machos sardos.
- Identificación y análisis de 11.763 polimorfismos de un solo nucleótido (SNP) de MSY.
- Construcción y calibración de un árbol filogenético MSY utilizando datos arqueológicos (hace ~ 7700 años).
Principales resultados:
- Descubrimiento de 11.763 SNPs MSY, de los cuales 6751 son nuevos.
- Desarrollo de un árbol filogenético MSY completo que incluya haplogrupos europeos y grupos específicos de Cerdeña.
- Identificación de estratos genéticos distintos dentro de Cerdeña, revelando la expansión de la población y los tiempos de coalescencia.
Conclusiones:
- El estudio proporciona detalles sin precedentes sobre la diversidad del cromosoma Y de Cerdeña y su lugar en la historia genética humana.
- El árbol filogenético calibrado ofrece información sobre el momento de la expansión de la población sarda y los eventos de coalescencia.
- La edad de coalescencia estimada de hace 180.000-200.000 años se alinea con las estimaciones anteriores del ADN mitocondrial, lo que apoya los orígenes humanos profundos.
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