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Reconstruyendo el origen de los isleños de Andamán
Kumarasamy Thangaraj1, Gyaneshwer Chaubey, Toomas Kivisild
1Centre for Cellular and Molecular Biology, Hyderabad-500 007, India.
Resumen
Las poblaciones "mongoloides" de las islas Andamán "Negrito" y Nicobar "Mongoloid".
Área de la Ciencia:
- Genética evolutiva humana La genética evolutiva humana es la genética evolutiva humana.
- Genética de poblaciones genética de poblaciones.
- Análisis de ADN antiguo Análisis de ADN antiguo.
Sus antecedentes:
- Los orígenes de las poblaciones de las islas Andamán y Nicobar han sido históricamente ambiguos.
- Estudios anteriores han ofrecido información limitada sobre el linaje genético de estas comunidades aisladas.
Objetivo del estudio:
- Investigar los profundos orígenes ancestrales de las poblaciones "mongoloides" de Andamán "Negrito" y Nicobar.
- Para aclarar los patrones de migración y el aislamiento genético de estos grupos de islas.
Principales métodos:
- Análisis de secuencias completas de ADN mitocondrial (ADNmt) de individuos andamaneses (Onge, Gran Andamán) y de las islas Nicobar.
- Análisis filogenético para determinar clado de raíces profundas y ascendencia común.
- Comparación de linajes de ADNmt con poblaciones globales para inferir la historia de la migración.
Principales resultados:
- En las poblaciones andamanesas se identificaron dos clados de ADNmt distintos y profundamente ramificados, originarios del haplogrupo fundador M.
- Estos clades andamaneses muestran conexiones con linajes encontrados en la India, África, Asia Oriental, Nueva Guinea y Australia.
- Las secuencias de ADNmt de Nicobarese revelaron una estrecha afinidad genética con poblaciones del sudeste asiático.
Conclusiones:
- Los linajes de ADNmt andamaneses sugieren la supervivencia en aislamiento genético desde una temprana migración "fuera de África" por humanos anatómicamente modernos.
- Los datos genéticos apoyan una historia ancestral distinta para los nicaragüenses, estrechamente vinculada a las poblaciones del sudeste asiático.
- El análisis del ADN mitocondrial proporciona información crucial sobre la población de las islas Andamán y Nicobar.
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