While a surname itself may give us only general information about the origin of a family, DNA-testing can give us concrete evidence for identifying and separating family lines. Y-chromosome DNA testing is especially helpful because the male Y-chromosome is handed down, father to son, unchanged through the generations, except for rare mutations which, in themselves, can be helpful indicators of branching. The accessibility and affordability of family DNA testing is doubtless the greatest technical advance in the history of genealogical research because -- at long, long last -- we have a tool to break down those brick walls!

We have been able to use the Big Y-500 and Big Y-700 to help separate the descendants of Henry Long by using the unique SNP associated with that branch.  When one person tests positive to a specific SNP, we know that all others who test positive to that particular SNP descend from the same male.  This helps us to place those individuals without a clear paper trail into a lineage with someone who does have the documentation to back up their lineage.