The short answer is "no."
I do not think DNA testing will ever be enough for tribal enrollment because of the way "blood quantum" is calculated. This is best explained by an example. (In this example it is assumed that each Native American parent is an enrolled member of their tribe with proper Certificate of Indian Blood documentation or the tribe's equivalent of this document.)
Take, for instance, these two families: (1) a 100% Navajo female marries a male of non-Native decent and (2) a 100% Hopi female marries a 100% Navajo male. Clearly family #1 will have offspring that are 1/2 blood quantum and can simply register the child with the Navajo Nation. Now consider family #2 which also will have offspring that are 1/2 blood quantum despite being 100% Native American. The reason--each tribe does not care how much total Native American bloodline an individual has, they only care about the bloodline of their tribe. Furthermore, an individual cannot be an enrolled member of more than one tribe.
Apparently the Bureau of Indian Affairs (BIA) does issue a Certificate of Degree of Indian Blood (CDIB) that reflects the total Native American bloodline of an individual. I'm not sure how widely accepted this document is since it is not associated with a specific tribe. Perhaps it can be used for scholarships that do not require declaring a tribe?
Essentially: It is entirely possible for an individual to be 100% Native American by bloodline and still not qualify to be an enrolled member of any of the tribes the person is descended from.
For a more detailed explanation please see:
Wikipedia: Blood quantum laws
Wikipedia: Certificate of Degree of Indian Blood
Good luck, you'll need it.