Dutch scientists have sequenced the a female human genome, reports the AP. The first human genome was sequenced in 2001; since then, scientists have mapped four male individuals' DNA. "It was time, after sequencing four males, to balance the genders a bit," says the lead researcher.
"Because the X chromosome has to do all the work in one half of the population—the males—selection has been tougher during human evolution," the researcher told DutchNews. "This means the X chromosome is less variable."