43 runs per base—of the target genome, 454 achieved accuracy of one error per 2,500 base pairs. The Harvard group had less than one error per three million base pairs with 7× coverage. To handle templates, both teams employed capture beads, whose size affects the amount of expensive reagents consumed. Our beads were one micron in diameter, whereas 454 used 28-micron beads in 75-picoliter wells.