To help me try to translate "DNA" into a more simplistic form, I've been reading helpful hints for DNA project managers accessed from the Kilgore DNA Project home page. One of the most interesting papers compared digit zip code interpretation to DNA interpretation & can be found by googling< "zip code analogy" DNA> . On a zip code, the 1st digit gives you the area of the country from 1 on the east coast to 9 on the west coast; the 2nd & 3rd gives you the regional PO; 4th & 5th gives the town and the last 4 gives you the carrier route or major customer. Basically as you add more #'s you get more details of location. Similarly as you go from a 12 marker test to a 25 & then to a 37 you get progressively more data on familial groupings. The 12 test (AKA low mutation rate test), 25 (medium mutation rate test) & 37 (high mutation rate test) with the 37 having almost double the 12 mutation rate-- like the zip code as you add more mutations, you get more detail. The paper suggests looking first @ all DYS #"s in the 12 test. I prefer John's method looking @ the values that seems to best define the various Kilgore lines, in our case DYS439. Either way we end up with the same conclusion opined by John; namely, those with a value of 13 rather than 12 probably have an earlier ancestor than those with a value of 12. The paper then recommends looking @ the 25 test -all DYS #"s from 1-25. Again I like John's method better; namely just looking @ pertinent DYS #'s in the 13-25 group John used DYS449 (I would consider also using DYS 458 in which all members but 2 have a value of 18). Again we get the same basic result-- a James W. group is identified. This is as far as I've gotten so far. Have to read some more of those Project Manager guidelines to see if something else pops up. It all makes me a little dizzy at times but still having fun learning. Jack T.