Dewees(e) Surname Project - Results

What follows is a summary of Project results to date.  (3-27-12)

All seven participants contain a Dewees(e) Y chromosome that is very similar to that of our common ancestor eight or nine generations back,  Garrett Hendricks deWees.  Of course we don’t know the exact makeup of Garrett’s Y chromosome, but based on our Y chromosome outcomes we can estimate his pattern for the 37 DNA marker sites that were tested for the seven of us.  Our Y chromosomes are simply copies of his which has come down to us with occasional mutations through the generations. 

 Out of the 37 marker sites, mutations occurred in only seven sites in our project.  Therefore, we all share the same DNA pattern at 30 marker sites, and it is assumed that Garrett had the same patterns at these sites on his Y as well.  For the remaining seven sites where occasional mutations were observed, we can deduce the most likely patterns for Garrett.  In a general way Garrett’s deduced outcome at one of these variable marker sites is the one that was most common among the seven participants. The deduced pattern at the 37 marker sites for our common ancestor, Garrett, is termed the Deduced Ancestral Haplotype (DAH).  See an estimate of Garrett's haplotype, the Dewees(e) DAH, at:  http://www.worldfamilies.net/surnames/dewees/results

Garrett Hendricks deWees had three sons- William, Cornelius and Lewis.  The genealogical relationships and Y-DNA outcomes for 37 marker sites among the seven participants are as follows:
 Descendants of William- C. Dewees and brothers A. A. Dewees and J. B. Dewees are fourth cousins once  removed.  A. A. and J. B. Dewees have equivalent Y DNA patterns and differ from C. Dewees at two sites .
Descendants of Lewis- M. F. Dewees and J.T. DeWeese are fifth cousins.  They differ at two sites.
Descendants of Cornelius- A. C. Deweese and  H. W.  Deweese are sixth cousins.  They differ at three sites.

Comparisons  of each participant’s Y-DNA pattern at the 37 marker sites (their haplotype) to that of Garrett Hendricks deWees (the Dewees(e) Deduced Ancestral Haplotype) are as follows:
William’s descendants differ from Garrett’s DAH at three or four marker sites.
Cornelius’s descendants differ from Garrett’s DAH at one or two sites.
Lewis’s descendants differ from Garrett’s DAH at one or two sites.

Dewees(e) family genealogists have documented that William and Cornelius are, in fact, sons of Garrett Hendricks deWees.  The case for Lewis as son of Garrett is strong but circumstantial (see article by Jack Vaughn and Ted DeWeese-http://boards.ancestry.com/surnames.deweese/358/mb.ashx).    The above comparisons offer support that Lewis possibly was a son of Garrett because the Y-DNA patterns of his descendants, M. F. and J. T. Deweese, resemble very closely Garrett’s DAH.  However, these matching DNA patterns also could be explained if Lewis were a close male relative other than son; for example brother, nephew, or uncle of Garrett.