I found a DNA study at this website: http://freepages.genealogy.rootsweb.ancestry.com/~gbonner/ne...

It provides the DNA sequences for the descendents of Giles Newton and James A. Newton (b. 1758 VA; d. abt 1838, KY). The sequences show that there is no relationship between the two. The study says that that James is related to John Newton of Westmoreland, VA. But, I'm not sure if I buy that theory because, it looks like the relationship was established by one sample.

I'm working on obtaining some of the court records that I mentioned earlier. Hopefully, these will provide more clues on the James Newton's of Caroline and Spotsylvania County. If I find anything out, I'll post it here.