"Another case in point is L840. So far, the few who have tested it are all positive and, up until now, also P109+, so on the FTDNA draft tree, L840 is associated with P109+. However, in compiling these matrices, I found someone who is L840+, but negative for P109 and L22, while positive for Z63. Therefore, the SNP is logically upstream of L22 and Z63. The question, now, is whether it is upstream or downstream of M253." [[I believe the quote above is the operative part of your message for L840. Concerning your last sentence --- the issue is not upstream or downstream of M253; rather it is present phyloequivalence to M253 or not. As long as L840 remains phyloequivalent to M253 you will have no way to tell which is upstream or downstream of the other. And that ambiquity may remain forever and be a fact concerning the underlying tree. There are presently over 30 known snps presently phyloequivalent to M253 with many of these available for testing. There is nothing special about L840 which is presently in the same situation. The tiny number of I1xL22 who have tested L840 is matched by most of those 30 phyloequivalent snps which have either hardly been tested or not tested at all since their discoveries and additions to FTDNA catalog. At least we do know L840 happened quite upstream --- actually upstream of the NODE which is MRCA to both Z63 and L22 --- a node necessarily earlier than both the Z63 and L22 mutational events. That's very early in time and close to the MRCA for all of I1, diminishing even further the chances a L840- M253+ will be found. A lot of money can be sunk into trying to split such phyloequivalences and with no guarantee of success; probably more useful investments into testing can be encouraged, especially if the recommendations are directed to the general hobbyist. This being March 2012, the association of L840 with P109 in a "draft tree" is an error or failure to keep up to date --- certainly no good guide to testing. That an I1xL22 is L840+ has been known by many of us, and certainly FTDNA, since November 2011. KN ]] -----Original Message----- From: Diana Matthiesen Some people test SNPs for the reasons given on this page: http://dgmweb.net/DNA/General/SNP-maxout-HgI1.html Diana On Behalf Of Kenneth Nordtvedt > Sent: Tuesday, March 06, 2012 12:59 PM > It is not clear why you would be urged to do L840? It seems far > upstream > and common to all I1.