A subset of X-chromosome genes seems to give females an extra degree of protection against cancer. This finding, which emerged from a study led by researchers at the Dana-Farber Cancer Institute and the Broad Institute of Harvard and MIT, is surprising because males also have an X chromosome, which might be expected to afford as much protection as the one unsilenced X chromosome in females. Yet some genes on the silenced X chromosome escape dormancy and function normally. These genes, it turns out, are crucial. {read more here}