Ra (founder of Human Design) described HD as the mechanics of the Not-Self. According to HD, some things come natural and easy to you, and many other aspects of your functioning are conditioned, and this is your “Not-Self” (undefined areas in your Bodygraph).
Once you understand this you can start living “the Experiment” and follow your Strategy and Authority that will set you free from conditioning and you no longer need to understand the mechanics of HD.

Gene Keys (GK), founded by Richard Rudd, focusses on the process of this transcendence through the practice of contemplation. GK is about allowing, accepting, and embracing your Not-Self, your conditioning” which GK calls “the Shadow”. GK doesn’t focus on the mechanics like HD, but offers “guided tours” of all the 64 ways of Being (HD calls these Gates, I Ching calls them hexagrams, and Richard Rudd calls them Gene Keys). GK’s first tour (Activation Sequence) focusses on your life’s work (what you are here to do), your evolution (what you are here to learn), your radiance (what you need to be balanced and healthy), and your purpose ((what deeply fulfills you).
The second tour (Venus Sequence) is about relationships, how you have learned to protect/defend yourself by closing your heart, and invites you on a path to reopen your heart and allow more love in yourself and in your life. The third tour (. ) is about prosperity, how you best thrive in the world.
For contemplating the 64 ways of being Richard Rudd distinguishes five spectra of consciousness for each Gene Key. Three are related to the Not-Self/shadow, one is about the process of transcendence (Gift), and one (Siddhi) is about the transcended state.