This is from FTDNA's newsletter: Case Studies in Genetic Genealogy ================================= In each issue of the Newsletter, we look at what Genetic Genealogy will do for your Family History research and present a case study. Case Study ========== I don't understand the tests. I have 5 exact matches then it says four of them have mutations. Recommendation ============== You took the 25 marker test. The results displayed on the Y DNA Match page first shows those whom you match at 12 Markers, and then 25 Markers. On the 12 marker test you matched 5 men at 12/12 and 3 more at a Genetic Distance of 1, or an 11/12 match. Since you share the same surname, you are quite likely related to all of them. You and some of the others also took the 25 marker test. On that test you had no 25/25 matches with any of the others. You had 3 matches at a Genetic Distance of 1, which would be a 24/25 match, and you had a Genetic Distance of 2 with 3 other men. Your results indicate that a mutation has occurred in your line, and you belong to a branch off that original line - a branch that presented specific mutations that characterizes it. ************* char's note: I'm sure this cleared everything up...:)