@Undertaker
Oro's labs got crushed and ruined a long while ago. So even if he had the DNA, not anymore. Oro din't have the chance to take care of his stuff.
@Panda
I din't mean his soul was sealed, i meant his body was sealed and trapped inside. But i forgot that Tobi took his body away and worked on it, so i guess his DNA could still be found. But then again, that stuff is with Tobi. Besides, the village elders knew well about Root, you'd always seen Danzo with that bunch. Even if they din't know much extra information, stuff that was related to the Uchiha, they would know as much as Danzou.
@Witness
Yea, you're right. He wasn't sealed. My bad for forgetting about that. I don't think it was the parents, frankly. Neither do i think it's Danzou. If i had to take a wild shot in the dark, i'd presume it was something completely unrelated, like you said. Awakening the rinnegan, or possibly doing something immense with Yamato's cells and bring back the first or something like that. We have not seen any of Yamato and Oro did say they're going to a place Sasuke remembers.