Thank you for the great chart, Sandy! I don't know how they are related either, but the Griersons, Milligans, and Mac/McAdams knew one another and intermarried way back in the 1500s and 1600s. I also noticed that some Milligans and Mac/McAdams were both merchants in Ayr back in, I think, the 1700s, but this is off the top of my head. From looking at their matches pages, my lines have somewhat closer matches to Milligans than to Griersons. As for O'Brien, of the five Mac/McAdam lines in M222 at 111 markers, four were tested from scratch by me, but Kit 65678 was originally tested to 37 markers and placed in the O'Brien project before I fished him out, put him in the McAdam project, and received permission to upgrade him. I think the guy who contacted him out of the blue was an O'Brien in the United States that Kit 65678 didn't know. Possibly it had something to do with an old legend about an Edmund O'Brien who fought in the Battle of Bloody Bay in the late 1400s. He was a gallowglass out of Ulster, and he was supposed to have settled in the Arisaig/Moidart area of the west coast Highlands about 25 miles northeast of the battle site. According to Kit 65678's genealogist (his first cousin) a priest in the Arisaig/Moidart area credits this Edmund with starting my little cluster of Mac/McAdam lines. So far there is nothing that strongly supports that legend, but DNA is instead showing a Lowland connection for what I used to think were strictly Highland Mac/McAdams. This Mac/Mc business has resulted in four of my lines in one place in your chart and the sole Mc in another part. They were all Mc until sometime after 1900, when they all started dividing themselves in the Irish Mc and the Scottish Mac. The testee for Kit 65678, who is closely related to the Mc (Kit 119699) actually went to the trouble to officially change from Mac to Mc back in the 1960s or so. After spending money to do that he now finds himself M222. Ironic! Well, I have so much research to do on the Lowland connections that I doubt I'll ever live long enough to get to the bottom of it. Thanks again for all your time and effort. Allene On 6/25/2011 11:46 PM, Sandy Paterson wrote: > David, > > An interesting grouping seems to be forming: > > Grierson/Milligan/McAdam/Mitchell/Reilly/McKenzie/O'Brien/Carey/McGill > > I have absolutely no knowledge of any kinship links between these surnames, > but you may have some thoughts. > > > Sandy > > >