Parts of the Lloyd Pye's "Everything You Know is Wrong" are tin foil hat stuff to the uninitiated. But he does a good presentation on gene splicing as part of his talk. He says aliens genetically modified a lower primate species to make humans. The "mistakes" give rise to many medical conditions unique to humans. Food for thought.

woops, here's the link: https://www.youtube.com/watch?v=e5qJYwfAju8