Purnell Bradford - Is There A Link?

There is a Purnell Bradford that I have run across in my research, but I have never found a link between our Rebecca Bradford and him.  Yet, there are intriguing similarities in their respective geographies.

Map showing Worcestor County and next-door Somerset County, Maryland

This Purnell Bradford is from Worcestor County, Maryland (born about 1770) and is listed in the white section of the Bradford DNA project chart (see following link) does not seem to be related to our William Bradford (son of our "Red Lion Sam" Bradford) who listed in the blue area, at least according to my very limited understanding of this DNA chart (I assume that the different colors indicate completely different lines, but please correct me if I am wrong!). Here is the link (sorry it's not a hot link...you'll have to cut and paste it into your browser):
file:///C:/Users/Ken/Desktop/Donna's%20Genealogy/BRADFORD/DNA/Bradford%20DNA%20Chart.htm  

And yet it is interesting to note that the Purnell Bradford family came from Worcestor County, Maryland,which is right next to Somerset County, Maryland where our Miller's first settled when they came to America.  Is this when the Miller and Braford families became acquainted?

Also, as you can see from the handwritten letter at the end of this post, the Purnell Bradford family eventually moved to Adams County, Ohio, and finally settled in the Maysville, Kentucky area.

It so happens that our Rebecca Bradford Miller's brother, William Bradford, and his wife, Margaret nee Parkinson, moved to Adams County, Ohio, and then to Maysville, Kentucky according to the paragraph in blue below which was shared with me by another Bradford family researcher.

That these two Bradford families (and possibly our Millers) wound up living so close to each other in three different locales seems almost beyond coincidence . 

Thoughts? Opinions? Any DNA experts out there??

William BRADFORD (son of Samuel BRADFORD & Sarah BRADFORD) was born on 8 Jan 1770 in Cecil Co., MD.  He died on 19 Oct 1862 in Maysville, Mason Co., KY.  He was buried in Bradford Cemetery, Sprigg Twp, Adams Co., OH.  William Bradford was a native of Cecil County, Maryland, but lived in Washington County for a number of years.  A few years after their 1799 marriage, William Bradford (1770-1862) and Margaret Parkinson Bradford (1780-1852) moved to Brooke County, West Virginia.  They built a flat boat in 1816 and moved down river to an area now known as Manchester, Adams Co., Ohio, and purchased a farm about four miles up river from Aberdeen, Brown County, Ohio, where they built a brick house in 1822.  Sometime in the 1840's they moved to Maysville, Mason County, Kentucky, which is across the river from Aberdeen, Brown Co., Ohio. William Bradford owned two slaves, both of whom were freed when the Civil War began.  Both he and his wife are said to have been buried in the family plot on their farm located on Lick Skillet Road between Aberdeen and Manchester, Ohio.