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Historia molecular y evolutiva del melanismo en los lobos grises de América del Norte
Tovi M Anderson1, Bridgett M vonHoldt, Sophie I Candille
1Departments of Genetics and Pediatrics, Stanford University, Stanford, CA 94305, USA.
Science (New York, N.Y.)
|February 7, 2009
Resumen
El melanismo en lobos y coyotes es causado por una mutación del locus K originada en perros domésticos. Este rasgo, seleccionado en los perros, se ha extendido en las poblaciones de lobos salvajes, influyendo en la diversidad del color de su pelaje.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- Genética La genética.
- Zoología Zoología Zoología.
Sus antecedentes:
- La diversidad morfológica es clave para la adaptación de las especies.
- Las mutaciones en el gen del receptor de melanocortina 1 (Mc1r) causan variaciones de pigmento en muchas especies.
- El melanismo del lobo está vinculado al locus K, no a Mc1r.
Objetivo del estudio:
- Investigar la causa del melanismo en los lobos grises (Canis lupus).
- Determinar el origen y la historia evolutiva de la mutación del locus melanistic K.
- Comprender cómo los rasgos domesticados impactan en la diversidad de sus parientes silvestres.
Principales métodos:
- Análisis genético de las poblaciones de lobos y coyotes.
- Investigando el locus K y su proteína beta-defensin.
- Examinar las firmas moleculares de la selección.
Principales resultados:
- La mutación del locus K que causa melanismo en los lobos de América del Norte se originó a partir de una antigua hibridación con perros domésticos.
- Esta mutación es prevalente en las poblaciones de lobos forestales y muestra signos de selección positiva.
- La misma mutación también causa melanismo en coyotes y lobos italianos.
Conclusiones:
- Los rasgos domesticados pueden transferirse a las poblaciones silvestres a través de la hibridación.
- La mutación del locus K pone de relieve la influencia de la domesticación en la diversidad morfológica de las especies silvestres.
- Este estudio revela una vía evolutiva única para la variación del color del pelaje en los cánidos.
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