Board Thread:Naruto Discussions/@comment-25369463-20140916215554/@comment-4688597-20140916232928

BeyondRed wrote: ItachiWasAHero wrote: Kabuto did say he was the closest to the Sage when fighting Itachi so he may have already integrated Hashi's cells, but maybe like Danzo he can't control it so he doesn't use it. He also only used Hashi cells to repair Sasuke's heart since it was fatally damaged.. Sasuke definitely has Hashi's DNA in him, not to mention Hashirama gave him his Chakra too.

We see Kabuto pumping flesh from his attached snake into Sasuke, so most likely if Sasuke has Hashirama cells, then so does Kabuto. Which would be weird, since Kabuto only ever attributed his regenerative powers to Orochimaru and Karin's life forces, not Hashirama's. Then again, Yamato never displayed regeneration or enhanced stamina like other Hashi-transplantees (on the contrary, his stamina seems rather lousy) so who knows, it may not be an entirely automatic thing.

Exactly. I think Kabuto just gathered Hashirama's cells that he's been working on and just used them to work on sasuke. There's nothing saying that he integrated them into himself genetically.