This is a incert from a former post discussing fanconi and mix B's…
if you wanted to be on the super safe side you could test for your mix for Fanconi. But, in my opinion, and educated guess....it is virtually impossible for a dog that is half basenji or less to get Fanconi. The current understanding is it takes two basenjis that are carrying a gene/s for Fanconi to produce it in their offspring. So, *unless a Basenji mix has one parent that is full Basenji and one parent that is half or more Basenji, they shouldn't have the genetic combination that makes Fanconi.
I dont really know for sure about testin mixes, but i plan on testing just to be on safe side.