Board Thread:Theories and Speculation/@comment-31405559-20170406151322/@comment-9782468-20170407133240

Why is it blue? Why does it turn the whites of his eye black? Why don't his veins bulge?

It could be a Byakugan. But considering the anime is using Kishi's art style, we can't assume it is a Byakugan because it just looks too different. Besides, if it was a Byakugan, I think Boruto would notice he suddenly had close to 360 degree vision/