Board Thread:Theories and Speculation/@comment-25283946-20150203145352/@comment-5407586-20150203194424

Actually, Blaze Release is a kekkei genkai, just not an "advanced nature" (which is a fanon term anyway) type. It's considered kekkei genkai since it is used through a dōjutsu.

And Kakashi said FIVE basic nature types, not seven. Jiraiya did say six when thinking about Nagato's training during the battle against Pain, but that was corrected to five in the volume release.