Está na hora de abandonar mais um erro científico nos livros didáticos de Biologia

Re-Write The Textbooks: Key Genetic Phenomenon Shown To Be Different Than Believed

ScienceDaily (July 2, 2009) — Because females carry two copies of the X chromosome to males’ one X and one Y, they harbor a potentially toxic double dose of the over 1000 genes that reside on the X chromosome.

To compensate for this imbalance, mammals such as mice and humans shut down one entire X-chromosome through a phenomenon known as X-inactivation. For almost two decades, researchers have believed that one particular gene, called Xist, provides the molecular trigger of X-inactivation.

Now, a new UNC study appearing online July 1 in the journal Nature disputes the current dogma by showing that this process can occur even in the absence of this gene.

“Our study contradicts what is written in the textbooks,” said senior study author Terry Magnuson, Ph.D., Sarah Graham Kenan Professor and chair of genetics, director of the Carolina Center for Genome Sciences and a member of the UNC Lineberger Comprehensive Cancer Center. “Everybody thought that Xist triggers X-inactivation, but now we have to rethink how this important process starts.”

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ALÔ MEC/SEMTEC/PNELEM:

Este erro, oops, 'dogma' vai para a lata do lixo da História da Ciência. Que tal me convidarem para fazer parte da douta Comissão que aprova os conteúdos sobre a evolução nos livros-texto de Biologia do ensino médio?

Alguém mais cético da capacidade heurística da teoria geral da evolução de Darwin (um Australopithecus se transformar em antropólogo) daria mais equilíbrio no conteúdo aprovado.

Do jeito que está é o mesmo que mandar cabrito tomar conta de horta...