Robert Chisholm, administrator of Clan Chisholm DNA Project has posted an update on the ScotDNA mailing list about significant results from his project.
Robert states that the Chisholm DNA results would appear to back up the clan origin story of a Norman origin, via the conquest, marriage into Roxburghshire, and "conquest via marriage" into the Highlands.
"Identified Old Chiefs line via several documented genealogies (modern Chief's line is female descent from 1888) , classic I1 Norse type identified by Ken Nordeveldt. Within Clan Chisholm this single type is representing 30-40% of Chisholm named project members. Large DNA footprint traceable back through England, a small amount in Normandy, and back to Scandinavia. Several large family groups (English) who match and would represent sibling lines of Norman family prior to the first representative to found the new surname de Cheseholme, in Scotland, during reign of David I."
"Other DNA in Clan: the majority represent R1b, but with some smaller family groups, predominance of British, but still significant numbers with Gaelic ancestry. Overall the Highland part of the Clan is likely to exceed 50% celtic base, as the I1 Norman type does include the Borders branch which has over time spread
throughout the lowlands and back to Northumbria (whence it originally came, as oral histories have the first de Cheseholme being a Norman Knight from Tindale)."
"So overall, a good result for DNA, proves beyond doubt the favoured origin foundation story, and all those origin myths about the men of the north, the Earl of Orkney, can be dispensed with."
The full original post can be read at SCOT-DNA/2011-07/1310603008