Nephilim DNA?

SMITHSONIAN COVER UP OF THE GIANTS?

The first hint we had about the possible existence of
an actual race of tall, strong, and intellectually
sophisticated people, was in researching old township
and county records. Many of these were quoting from
old diaries and letters that were combined, for
posterity, in the 1800s from diaries going back to the
1700s.

http://www.freerepublic.com/focus/news/720497/posts

Serpent Mounds: http://greatserpentmound.org/articles/giants3.html