Palabras clave
Regulación genética
Función del gen
Genómica Genes
Gene regulation
Gene expression
Genomic
Cómo citar
Resumen
Definir un gen es una tarea difícil y cada vez más complicada. Dado su interés en muchas disciplinas, algunos pensamos que debe reflejar un concepto global que incluya la mayoría de los elementos estructurales y funcionales que lo componen. En esta revisión se analizan los hallazgos que han ayudado a construir un nuevo concepto de gen, enfatizando en los descubrimientos recientes que han obligado a modificar la definición tradicional de gen, resumida como “secuencia de ADN que codifica la información para la síntesis de proteínas o ARN”. Entre esos hallazgos están el “splicing” alternativo, la recombinación somática en los genes de las inmunoglobulinas, la regulación de la expresión génica, ya sea inter- o intra-cromosómica, por secuencias reguladoras, por mecanismos epigenéticos o por ARN; la naturaleza de los transcriptos según el sentido de la trascripción, los transcriptos quiméricos, la repetición de exones y la herencia extragenómica. Integrando estos fenómenos y su impacto funcional podemos definir los genes como un conjunto de secuencias de ácidos nucléicos que determinan la expresión y regulación de una característica heredable.
Citas
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