David McCord 1745 vs David McCord 1747 DNA variation

Question

My 6th great-grandfather was David McCord (10 Mar 1747 - 04 Jan 1818) married to Anne Lee Shipley (28 Apr 1746 - 1828). When I started researching over 20 years ago there was an active McCord Family Association online which claimed that all McCords were descended from the same line that went back to a clan chief in Scotland who was killed in battle in 1689, after which the clan fled Scotland to the new world after some time in Northern Ireland, led by William McCord "The Immigrant". The Association had family line designators set up, and according to them, my line through David McCord was "Family B".

Fast forward 20 years, and (according to the DNA experts, which I am NOT one) the DNA now says that there are in fact two different sources for McCords today (type 1a and type 1b), and they diverged from each other about 1900 years ago - WAY before 1689. As I understand it, William the Immigrant was type 1b, and my Family B is type 1a.

The current entries in WikiTree make my David a grandson of William the Immigrant. The DNA disagrees. Furthermore, I have letters written long ago by a grandchild of David which say that David was not born here, but "came from across the sea". I do not have any information on his parents.

William the Immigrant DID have a grandson named David, but I believe this a different person from my ancestor - mostly due to the DNA evidence, but also there seems to be a difference in date of birth - 1745 vs. 1747. But of course, birth dates back then can be iffy.

All of this is to ask - what do I do with this information on WikiTree? The manager of David's profile has given me permission to make appropriate changes if I have proof. I find the divergent DNA to be fairly compelling, but I don't know if it's enough. Maybe more important, there are hundreds - maybe thousands - of descendants from the two David McCords. Splitting them into the two different individuals that I believe them to be would be a gargantuan undertaking, and would upset many, many descendants' trees based on long-standing beliefs.

On the one hand, it makes some sense to let sleeping dogs lie. On the other hand, I do believe that the status quo is incorrect. If I do decide to shake up the apple cart, I doubt that I would be able to sort out all of the repercussions alone.

Comments

Welcome to WikiTree, Bill. I hope some of our Scotland team colleagues and those from the DNA project may be able to assist you in further researching what the DNA testing appears to be telling you. The family association would be far from the first to make the claim everyone of surname X descended from a single person or immigrant -- only to have that later shown incorrect. I've added the DNA and Scotland tags to your question to get some more of the appropriate eyes on it.