Board Thread:Boruto Discussions/@comment-30965052-20170128171940/@comment-32175822-20170601225509

"When an Ōtsutsuki implants the Hyūga clan's Byakugan, the combination of their chakra will transform the Byakugan into the Tenseigan."

So basically there is a big chance that Boruto's Eye is not the Tenseigan since he does not have or has not yet manifested the Byakugan yet and he does not have pure Otsutsuki blood.

But my theory is that, it is a new variation since Boruto has the Hyuga Blood and the Uzamaki/Senju Blood.. Not to mention Naruto the Kurama and traces of all the tailed beasts when they conceived Boruto.. So its highly likely that this is a new Kekkei Genkai/Dōjutsu..