Anita wrote: > group of college students who they did a DNA study on. I believe it was > a Mitochondria study, but I didn't get to sit and watch it all. > > Before hand they predicted who they would have the most similarities > with. Asian students thought they would match other Asians, African > American to other African Americans, etc. If the group of students included both males and females, then the test was almost certainly mitochondrial DNA. Some of the types of mtDNA are very widely dispersed, much more so than a lot of the Y DNA types. One distinction between the commercial DNA tests for the two is the underlying mutation rates -- the markers tested for Y DNA are strings of DNA that can change length relatively easily, i.e., once on average in 500 generations, but the markers for mtDNA are individual bases that can spontaneously change, but only once on average in a million or so generations. By looking at hundreds of different bases, you can find lots of these variations, but the whole process is so slow that the mtDNA patterns have a chance to spread far and wide before another mutation comes along. That means mtDNA doesn't help much with most genealogical questions. (It's notable success was in confirming the identity of the skeletons of the murdered Romanovs found in Siberia.) The advantage of Y DNA is that the time scale of mutation is fast enough that there are lots of different patterns around, but slow enough that a genealogical study like this Sweet project will run into only a few mutations (which can be identified as such), so that differing Sweet lines can be sorted out (assuming that there indeed are different lines). John Chandler