Board Thread:Naruto Discussions/@comment-25645405-20141128183407/@comment-3279282-20141202021224

It is no logical assumption that only the five basic natures can make up advanced natures. The chapter with Kakashi's explanation makes it very clear that Yin and Yang are not part of the five elemental natures and if I remember correctly, he even says that combining two of the basic natures to create a new nature is what is called a Kekkei Genkai. The part about Yin and Yang is only touched upon at the end of the explanation and even then, they postponed explaining those two. And last but not least, since Yin and Yang are no elemental natures, they simply can't be used to create advanced natures.