I've said about surgebinding, that it has a genetic component only insofar as personality is partially genetically inherited (and also derived from how you were raised as Telcontar noted)
Also the Shaod never takes anybody but those of Arlish descent, not even Jindoese people, who may well follow Devoton's intent. So it requires both genetics and the proper actions, and we are surmising on the actions (although it's a very plausible theory).