Geographical plots of ancestral homeland


Mapping DNA Projects

Genetic genealogy projects involving mapping try to compare latitude and longitude origins of persons with the similar Y-DNA signatures so that their genetic homeland in the era of surname formation can be identified.

In general, precise identification of geographic origin depends on two important factors:

  1. Resolution

    Having sufficient resolution in the DNA tests to indicate that the time-to-most-recent-common-ancestor (TMRCA) is 1,200 years or less.
    • Effectively that requires a match of 33 or greater on 37-marker Y-STRs descended from the same SNP haplogroup. In some cases a 67-marker upgrade as well as SNP testing may be recommended.
    • A shared segment of Autosomal DNA of 30 centimorgans (cM) or more can also provide a match that is usable for the identification of geographic origins.
    • Matches on NextGeneration sequencing tests with large numbers of semi-private SNPs can also provide sufficient resolution for geographic identification
  2. Matches with Geography

    Having matches whose geographic origin are known with a degree of precision. Ideally this would mean finding and testing persons in the ancestral territory with a long geographical continuity such as traditional farmers. Failing that, persons with a good paper genealogy trail may provide geographical pointers.

Tools for Geographic Analysis of DNA Results

Genetic Homeland Finder Tool

Comparing map plots of surname records of persons with genetic genealogy matches with tools like the Genetic Homeland Finder tool can show patterns that are not easily recognized in traditional genealogy records.

So if you are searching for the PLACE where your paternal ancestors came from, you've come to the right project. Take a look at your Y-STR matches and compare what is known about their geographic origins.

Links for More Information