If you are positive for any SNPs down one branch, you cannot be positive for any SNPs down another branch. The further down a branch you go, the nearer to the present day you move. So testing newer SNPs eventually allows you to merge your traditional paper tree with your new genetic SNP tree.
New SNPs are discovered from Y-genome sequencing, from Public Genomes, FGC Full Genomes Elite, and FTDNA Big-Y. So if you choose Y-genome sequencing, you not only get all of your SNPs and Variants, you also help the genetic community by adding new SNPs to the ever growing SNP pool. That way, others can test 'your' SNPs, and you will get many genuine matches, some in a recent time period.
If you require any advice regarding the testing of SNPs and STR markers, please do not hesitate to ask one of the I1-Z140 Project Admins.
Our Z140 Project Tree [work in progress]. At the top of the FTDNA Z140 Project 'Activity Feed' page you can see the updated Z140 Tree, based on FGC Elite, Big-Y and other SNPs test results. Everyone on the Z140 Project has been placed in a predicted subgroup, based on STR markers, and whatever SNP testing members have taken. Those who have tested FGC Elite and Big-Y have had their results analysed by this project, and have been placed in their new subgroup, with a new terminal SNP. Almost all of the A-series I1-Z140 Project SNPs are ones discovered by this project, from Y-genome analysis, and are listed at YBrowse.
You are invited to join the Facebook 'I1-Z140 Project' at: https://www.facebook.com/groups/I1.Z140.YDNA.Project/
'I1-Z140 Project' at YFull.com: http://www.yfull.com/groups/i1-z140/
current YFull 'I1-Z140 Tree' https://www.yfull.com/tree/I-Z140/
The most-likely-STR-trees show the most-likely phylogenetic trees; here for Z140 and it's subgroups: F2642, AS-6 Harvey et al, AS-5, AS-3, AS-EE, Small groups, AS-814, L338
Note: the most-likely-STR-trees show the most-likely phylogenetic trees. In some cases SNP's or multiple STR's (dependent on the mutation rates) give strong evidence for the lines. In other cases only one mutation of an STR with high mutation rate give indication for a separate line. The lines improved in quality as more people measured Y-111 STR's. People in the small groups and individuals are also advised to measure SNP F2642 and Z2535.
A haplogroup is a group of descendant individuals from a single founder who all share a common SNP mutation. Individuals can test for these SNPs to determine their haplogroup assignment, which is often reflective of distant geographic ancestry. Membership in a particular haplogroup thus indicates broad population and geographic ancestry while other mutations in descendant haplotypes can reflect recent genealogical ancestry.
A SNP (single nucleotide polymorphism) is a variation in DNA sequence between individuals involving a difference at a single base-pair. SNPs generally have lower mutation rates than STRs and are often sufficiently stable to robustly define haplogroups.
"Private" SNPs/Novel Variants:
"Private" SNPs on the Y chromosome correspond to relatively recent mutations that have not yet been observed in a significant number of other individuals in the same haplogroup. Some of these will eventually be incorporated into the Y-tree with further research. Others may provide clues about recent genealogical ancestry.
STR (short tandem repeats) are a type of molecular marker consisting of short DNA letter repeats (such as CACA). These markers have a high rate of mutation and are accordingly useful in determining population genetic differences. In the Y chromosome line, SNPs and STRs in conjunction serve to show differences between individuals and groups in their DNA lineages. In short, STRs are one part of the puzzle in everyone's Y chromosome DNA heritage.