Board Thread:Theories and Speculation/@comment-5012682-20150620162706/@comment-5539377-20150624021856

I believe affinities for chakra natures are hereditary to an extent. Genetics in real life is rarely so definite as many of you are suggesting. If you have brown eyes, there is a possibility your child may have brown eyes, but not a certainty. I believe chakra affinities to work very similarly to this. This extends to clans, obviously, such as the Uchiha and Sarutobi. However... as some of you pointed out, it is not one hundred percent. I am inclined to believe that MOST Uchiha have Fire Release as an affinity, but we have exceptions such as Sasuke, who almost certainly has an affinity for lightning. Also, remember that any shinobi can potentially learn any chakra nature. Therefore that aspect is not genetic. An affinity is the nature one is able to learn most easily, of which their chakra has a natural tendency for. We do not know, for instance, whether Hinata's affinity is fire or lightning (personally, I'm more inclined for the former for a number of reasons), and so cannot say with certainty that Boruto inherited that from her.