Is Senju/Hashirama DNA really relevant in obtaining rinnengan?
In this discussion, I will raise question to the method, we've been tricked into believing, as the method to awakening rinnengan. Shortly my point is, that you simply need EMS and senjutsu to awaken rinnengan. And not senju/Hashi DNA, as commonly believed. Of course this is a discussion, so feel free to read the long version below, and bring your opinion if you even care.
What if it isn't Hashirama's DNA, that leads to rinnengan?
Why do they all take Hashirama's DNA, and not just some other random Senju? It has to be Hashirama's DNA, but why is that? Even a desperate Danzou acquired Hashirama's DNA long after his death.
Lately a lot of perspective has been put on sage mode, and how it seems to be the true origin to how humans learned to use chakra, which is just a cheap version of senjutsu. You could say that chakra is the senjutsu, which lies within ones body. The Ridukou Sennin most certainly mastered the use of senjutsu as well, since it's the only way to fight the Juubi (though he could have sealed it without fighting, but that is just an unrealistic theory...).
This belief made me realise a few things in the key to awakening rinnengan. The major key factor is, that the Ridukou Sennin lived many decades ago. The DNA that was passed on to his sons, have long since been halved 100's of times. In other words, it's just a minor fraction of that DNA, that is left. So obtaining the "ultimate" DNA to awaken rinnengan is a long lost fairy tale.
What the sage gave to his 2 sons were physical energy and eye powers. The Uchiha can awaken EMS, which is required for rinnengan (i.e. the eye powers). The physical energy may as well come from senjutsu, since that is exactly what senjutsu is. A sort of energy boosting ones physical abilities, when mixed with your own chakra.
So how did Madara obtain the rinnengan? Well frankly he took a part of Hashirama's tissue, and likely there was still a fraction of senjutsu in this part, and after a long time, Madara's body got adjusted to the senjutsu, and you could say, his body learned to cope with it on its own. It was at this point he awoke the rinnengan, foolishly believing it was the senju/hashi DNA (roughly speaking, lol).
Anyway, give your opinion. I know I am denying manga facts stated by Kishi, but Kishi has denied many of his own facts later on before, just pull another trolling plot down on us. This may as well be one of those!