Add Yahoo as a preferred source to see more of our stories on Google. Summer McKesson poses at her home in Atlanta on September 26. - Austin Steele/CNN Summer McKesson struggled to breathe for years.

One of the world's biggest genetic databases comprises DNA data donated over the years by more than a million retired military service members. It's part of a project run by the Department of Veterans ...

Summer McKesson struggled to breathe for years. Doctors told her it was because her blood would not stop clotting – and they couldn’t figure out why. A single clot alone can be lethal; but the ...