Un estudio de la Universidad de Michigan cuestiona la teoría neutral de la evolución

Un nuevo estudio de la Universidad de Michigan sugiere que las mutaciones beneficiosas son más comunes de lo que se pensaba, pero a menudo no logran propagarse porque los entornos cambian demasiado rápido. La investigación propone una visión revisada de la evolución molecular.

Investigadores dirigidos por Jianzhi Zhang examinaron las mutaciones en levaduras y E. coli utilizando escaneo mutacional profundo. Descubrieron que más del 1 por ciento de las mutaciones que cambian los aminoácidos eran beneficiosas, lo que implica que más del 99 por ciento de las sustituciones deberían ser adaptativas en condiciones estables. Sin embargo, esta tasa supera con creces lo que se observa en la naturaleza.

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