Board Thread:Theories and Speculation/@comment-35448581-20160502192848/@comment-1872728-20160506151617

Tenseigan is definitely a dojutsu. The simple fact that you can take it out while keeping the abilities basically shows it.

I do think that the Sharingan line originated from the Byakugan line, or rather, the Sharingan line is a combination of the Byakugan line and the Sage Mode line. First up, Rinne Sharingan is the combination of Otsutsuki's Byakugan (original Dojutsu) and Shinju's fruit (original Senjutsu). Of course, this eye is manifested as a new eye rather than on her original ones for some symbolic reason. Then the Sharingan line is then passed down to Hagoromo while the Byakugan line is passed down to Hamura, and the Sage Mode line is learnt by the Three Great Sages.