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Genética molecular de la visión humana del color: los genes que codifican los pigmentos azul, verde y rojo
Science (New York, N.Y.)
|April 11, 1986
Resumen
La visión humana del color se basa en tres pigmentos sensibles a la luz. El análisis genético revela que los genes de pigmento rojo y verde se agrupan en el cromosoma X, lo que explica las variaciones de visión del color.
Área de la Ciencia:
- Genética La genética.
- Biología Molecular Biología Molecular
- Visión Visión Ciencia Ciencia.
Sus antecedentes:
- La visión humana del color está mediada por tres pigmentos distintos sensibles a la luz.
- Comprender la base genética de estos pigmentos es crucial para comprender la percepción visual.
Objetivo del estudio:
- Para aislar y secuenciar clones de ADN que codifican las apoproteínas de los pigmentos humanos de visión de color.
- Para analizar las relaciones evolutivas y la organización cromosómica de estos genes de pigmento.
Principales métodos:
- Aislamiento y secuenciación de clones genómicos y de ADN complementario (ADNc).
- Deducción de secuencias de aminoácidos de secuencias de ADN.
- Análisis comparativo de secuencias para determinar las relaciones evolutivas.
Principales resultados:
- Las secuencias de aminoácidos deducidas de los pigmentos comparten aproximadamente un 41% de identidad con la rodopsina.
- Los genes del pigmento rojo y verde exhiben una alta identidad mutua (96%), distinta del gen del pigmento azul (43% de identidad).
- El número de copias del gen del pigmento verde varía entre los individuos; se propone que los genes del pigmento rojo y verde formen una matriz en tándem en el cromosoma X.
Conclusiones:
- La arquitectura genética de los genes de pigmento rojo y verde en el cromosoma X probablemente influye en las variaciones en la visión del color humano.
- La alta similitud de secuencias entre los pigmentos rojo y verde sugiere un reciente evento de duplicación génica.
- La distinción del gen del pigmento azul apunta a una divergencia evolutiva anterior.
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