Thanks for all the replies. Some of you mentioned ridgeback, and my vet thought there could be some too, but she's much smaller than that, so certainly a mix if that's the case. The barklessness, complete lack of odor, coloring, general shape and upright ears made me wonder. I agree though, especially as I've researched more, if there is any Basenji in her, it's mixed with something. Found several pictures of Basenji/shepherd mixes that look a lot like her too, and would account for the larger size, straighter tail, and the slight differences in snout, head and ears. Thinking about doing the DNA thing, even if its not perfect, to see if that sheds any light. The curiosity is killing me.