La inversión del sexo de la temperatura implica la dosificación del gen del sexo en un reptil
Video Experimental Relacionado
Updated: Jul 15, 2026
10:43
Dissection of Larval Zebrafish Gonadal Tissue
Published on: April 26, 2017
Alexander E Quinn1, Arthur Georges, Stephen D Sarre
1Institute for Applied Ecology, University of Canberra, ACT 2601, Australia. quinn@aerg.canberra.edu.au
Science (New York, N.Y.)
|April 21, 2007
Resumen
Las altas temperaturas pueden revertir el sexo genético en los reptiles, convirtiendo a los machos ZZ en hembras fenotípicas. Esto desafía la comprensión previa de la determinación del sexo y sugiere un nuevo camino evolutivo para la determinación del sexo dependiente de la temperatura (TSD).
Área de la Ciencia:
- Herpetología herpetología.
- Biología evolutiva Biología evolutiva.
- Genética La genética.
Sus antecedentes:
- La determinación del sexo de los reptiles suele ser genética (cromosomas sexuales) o ambiental (temperatura).
- Estas dos modalidades se consideraban previamente mutuamente excluyentes.
- El papel del cromosoma W en la diferenciación femenina no estaba claro.
Objetivo del estudio:
- Investigar la interacción entre la determinación genotípica del sexo y la determinación del sexo dependiente de la temperatura (TSD).
- Para determinar si la temperatura de incubación puede anular la determinación genética del sexo en los reptiles.
- Explorar las implicaciones evolutivas para los mecanismos de determinación del sexo.
Principales métodos:
- Estudió una especie de lagarto con cromosomas sexuales ZZ/ZW.
- Manipulación de las temperaturas de incubación durante el desarrollo.
- Desarrollo del sexo fenotípico observado en relación con el genotipo y la temperatura.
Principales resultados:
- Las altas temperaturas de incubación dieron como resultado que los machos genotípicos ZZ se desarrollaran como hembras fenotípicas.
- El cromosoma W no era esencial para la diferenciación femenina bajo estas condiciones.
- La evidencia sugiere que un gen de determinación masculina sensible a la dosis en el cromosoma Z es sensible a la temperatura.
Conclusiones:
- La determinación del sexo dependiente de la temperatura (TSD) puede anular la determinación genotípica del sexo en algunos reptiles.
- El cromosoma W puede no ser universalmente requerido para el desarrollo femenino en especies de TSD.
- Este hallazgo propone una nueva hipótesis para la evolución de la TSD y el papel de los cromosomas sexuales en los reptiles.
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