The Smith DNA project is a surname project where, primarily, YDNA STR results are compared by haplogroup to find matches. Members can look at FamilyTreeDNA matches by logging on to FTDNA; FTDNA shows which testers from within the entire database of testers, regardless of surname, a member has a match with. Depending on how many markers match versus how many do not, a person is deemed to be related to someone else on a range of very tightly related to not related.

What about SNPs? The...