Board Thread:Theories and Speculation/@comment-734582-20150712141917/@comment-734582-20151205133142

LoneNinja wrote: What if the Tenseigan is just some mutated eye I think this is pretty much a given. Personally, i believe that the same chakra reacts differently to different people. Six Paths chakra seemed to react mostly to Kaguya's body (granting deadly bones, hair, immortality). In Hagoromo and Hamura, it reacted strongly to their eyes (and so specialized in Rinnegan and Tenseigan). It's not clear how, but it seems that Kaguya's abilities (e.g. deadly bones) were dormant genes in Hagoromo and Hamura. It seems that this lack of abilities allowed the Six Paths chakra to specialize better.

I believe Sasuke has a form of rinnegan beyond the original, where the Mangekyou powers remain (rather than Madara where it too seems to be drowned in the Rinnegan), likely because Hagoromo directly gave him that power and so could preserve the Mangekyou aspect. LoneNinja wrote: you probably need both Ham and Hag to get Rinnesharingan. You only need to possess the "power of rinne" and the power of the biju. Naruto and Sasuke needed to cooperate to undo IT because each only has half the power of Rinne (Yin/Yang)