Hmmm. Are you trying to say that Native Americans who are also alcoholics exhibit specific psychological symptoms not present in non-Native American alcoholics?
You are trying to say that you have no idea what your topic is, but you heard something about how alcoholism has a higher prevalence among Native Americans than among the general population in the U.S.
Do Native American alcoholics receive different treatments than non-Native American alcoholics?
I am no expert in this subject, but I think you should be able to perform a journal search at your local library.
Talk to the prof if you are still stuck.