I say not aliens, they are either:
- from a Parralel dimension
- from the future and thus more slightly evolved.
- Or peaple taken in the past then altered by aliens (like the 4400) or altered from people in the future.
My bet is they are from the future, it makes sence with the one percent DNA difference.
Yep, that's my take. They're from the future, and have come back to 'change the past' and help save hummanity by averting The Event™ (which happens in their timeline, thus requiring their travel back to our time.)
Can you say, cliche?

But yeah, I'm done watching. I may check a hread once and a while (if they continue being posted); but it's not worth wasting an hour of my time each week on this.