Battle of the Sexes - ix

What makes a man? His clothes? His car? His choice of scotch? The real answer, says Brown University biologist Erica Larschan, is the newly understood activity of a protein complex that, like a genetic power tool, gives enzymes on the X-chromosome an extra boost to increase gene expression.

Men must increase gene expression on their lone X-chromosome to match the two X's possessed by women. A new study explains just how men manage to do that.

In mammals, cells therefore work to emphasize, or "upregulate," the lone X-chromosome in males and de-emphasize, or "downregulate," the extra X-chromosome in females.

I'm not sure of the significance of this study. Men trying to match up is understandable but why do women try to match down? What are those restrictions at cell level?

Via Science Daily