Seven generations? I have often heard shamanizers refer to 'shamanic genetics' or the spiritual passing of life patterns from generation to generation. Along those lines of thought - to me - "seven" can mean "in the fullness of time" or at the "perfect" time or literally "7" or multiples thereof, and generations can mean generations of anything from quarks to universes, and more.
But...is it necessary to invoke any notion of "shamanic genetics" or any other metaphysical theory to explain what passes down among humankind? Here is a site devoted to scientific genetics and genealogy: http://www.webfamilytree.com
~ Elizabeth