Description of Y-DNA Haplogroup Tracker Path Maps

• Men's Y-DNA maps are based on 700 plus markers on their Y chromosome which is passed father to son. These markers can mutate (deferent values) over the generations and the mutations are also passed father to son. This map is a mutation tracker path. Haplogroups are the names given each unique combination of values for the Y-DNA 700 plus markers. Originally Y-DNA testing looked at 12 markers, the 25, 37, 69, 111 and now over 700.
• The International Society of Genetic Genealogy (ISGG) is a group of Y-DNA experts who developed the Y-DNA tree we use. They first figured out the source combination of markers (they called it Adam) with no mutations as a base. They then identified the mutation branches and then branches of branches etc. The key is each Haplogroup is a subset (derivative) of a Haplogroup above it with identical DNA except for a mutation (value change) of a marker. ISGG has a graphic tree of all known Haplogroups and how they inherit up and down the tree based the presence or absence of mutations. So the inheritance of a modern Haplogroup has a clear single path from Adam. The map on the left shows the Haplogroup for our tester (or a higher level Haplogroup if our group is too small for identifying a location) and each Haplogroup it was inherited from back to Adam. The map on the right is a closeup of the most recent Haplogroups in our path.
• The time scale is based on average DNA mutation rates and is of course an estimate as we not know all specific dates for individual mutations.
• Globetrekker (Family Tree DNA) estimates the geographical ancestor locations and migrations path of the these Haplogroups across the world based on the Y-DNA from living men and user-reported ancestral locations but also ancient DNA results from archaeological remains. As more tests are done on living men and archaeological remains, the maps will become more accurate.