Here's an interesting read called the "Biology of Belief' by Bruce Lipton. He make the argument that perception and environment has the major role in determining your life and health as opposed to the idea the genes determine your fate.
Another gentleman who's done some great work in this same concept is Dean Ornish (check out this 5 minute talk Your Genes Are Not Your Fate & Healing
http://www.ted.com/talks/dean_ornish_says_your_genes_are_not_your_fate.html
http://www.ted.com/index.php/talks/dean_ornish_on_healing.html
This seems true to me, that happiness and peacefulness are our natural state. That we don't need to find it, we need to stop doing things that disturb it.
