Factores genéticos que inciden en la resistencia a enfermedades infecciosas en salmónidos y su aplicación a programas de mejoramiento

Archivos de Medicina Veterinaria (Impact Factor: 0.31). 12/2009; 42(1):1-13. DOI: 10.4067/S0301-732X2010000200002


El control de las enfermedades infecciosas es fundamental en el éxito del cultivo del salmón. El mejoramiento genético de la resistencia a enfermedades puede otorgar una opción factible y sustentable para el control de éstas. La Selección Asistida por Marcadores Moleculares (MAS) o Genes (GAS) se proyecta como una valiosa alternativa al mejoramiento convencional de la resistencia. Sin embargo, para implementar esta metodología es necesario el conocimiento previo de los factores genéticos involucrados en el carácter. En este trabajo se revisan y se discuten los aspectos más relevantes de la resistencia genética a enfermedades infecciosas en salmónidos y su aplicabilidad a programas de mejoramiento. En primer lugar, se presentan brevemente las enfermedades infecciosas más relevantes a nivel nacional. Además, se incluyen aspectos relacionados con el mejoramiento convencional para este rasgo cuantitativo, tales como criterios de selección, variación genética de la resistencia y correlaciones genéticas con otros caracteres de interés productivo. Por otra parte, se revisan tres aproximaciones moleculares utilizadas en la identificación de los factores genéticos involucrados en la resistencia: genes candidatos, con especial énfasis en el complejo mayor de histocompatibilidad (MHC) o genes MH, detección de loci de efecto cuantitativo (QTL) y estudios de expresión génica. Finalmente, se revisa y se discute en relación a la utilización de esta información molecular en la implementación de programas de mejoramiento genético que incluyan la resistencia a enfermedades infecciosas dentro de su objetivo de selección.

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