Who are his ancestors & descendants? What surname did they use?

http://www2.census.gov/prod2/decennial/documents/1790k-03.pd... Original page 58
1790 US census Ninety-Sixth District, Abbeville County, SC
Thrith, Joseph
Free white males of 16 years and upwards including heads of families: 1
Free white males under 16 years: 1
Free white females including heads of families: 3
All other free persons: (no entry)
Slaves: (no entry)

Abbeville County, SC is in the western part of the state, he might possibly be related to either GA or AL Thrifts as well as the known SC Thrifts?

I sure hope some South Carolina & Alabama Thrifts will sign up for a DNA test so we can look into their origins.
http://www.familytreedna.com/public/Thrift-Frith-Firth/

(We still need one more GA Thrift, too, to confirm the unexpected results we now have from one test.)

thanks
Richard Thrift

Apparently the census-taker should have spelled Joseph's name as Frith instead of Thrith. There are Friths in the area, though the ones who posted here couldn't trace back to Joseph:
http://genforum.genealogy.com/frith/messages/282.html

I'd still like to get these descendants into the DNA project. It may even turn out that some of the SC Thrifts & Friths are related.

Richard