thanks for the info ... one of the brothers was adopted without his knowledge. I don't know if we can get him to provide another DNA test. Based on the results that we do have, are there other explanations for the one marker difference? I mean, is it possible for two men to have that much of a match and NOT be brothers? No matter what, they share a male ancestor, correct? So if not the same father, probably the same grandfather?
Sorry I'm so lame on this ... I don't understand enough about how the DNA tests work. Thanks for your help.