I have not yet begun to track DNA, but I had been thinking that this is another case where "pseudo" people would work in TMG. I thought I might have the record be a "person".  Depending on the type of test it could be either Male or Female.  One custom tag type would have Principals be this person and the "real" person of this test to show it was their test.  Then I thought of having a custom tag type to document interesting features of the test. Another custom tag type might link this test to a matching test "person" describing the degree of match.  I have even been considering how I might use ancestor/descendant relationships of such "persons" to reflect the degree of match and so that TMG and SecondSite charts could be used. Finally I considered a separate custom tag type to link "real" people together, perhaps in the History group, where each person's Witness memo describes their relationship to this group of people. Hope this gives you ideas,