Hi Louise, I have been researching the line of Johnson Adams b. 1785, of Sevier Co. TN for over 6 years and have collected much information to share.In answer to your main question, no, to my knowledge no one has determined who Johnson Adams parents might be.The first I find him anywhere is in Sevier Co. TN in 1813 in a petition and he is already an adult.His answer to the place of birth question in the census records is "unknown" so there are no clues to follow there, but I suspect he was from NC.
As for the information you found where Johnson Adams married Nancy Burchfield...this is an ERROR!The Rev. Johnson Adams performed the ceremony for his son William who married Nancy Burchfield.This occurred December 14, 1837 in Blount Co. TN and I have a copy of the marriage record to back this up.Somewhere along the way, somebody made a transcription error and that error has been perpetuated in books and online unfortunately.Hope this sets the record straight.
I am interested in learning what you have found in your research of Johnson Adams and his descendants and am willing to share.Please contact me! Lorien Gunsallus