Leslie O'Hanlon is fascinated by the potential new knowledge that DNA tests for genetic ancestry may provide. But before handing over more than $200 to a genealogy-driven DNA testing service for a test that may be able to tell her where in Africa some of her ancestors may have come from, she explores the pros and cons of ancestral DNA testing. Most genealogists will agree with Leslie than any new knowledge is worth the cost, but it is still important to understand what you can and can't learn from a DNA test.