04 January 2007

Where are we now? Update #7

Interpreting the results in relation to the current state of knowledge.

(We apologise for the delay in issuing this update while we waited for a number of 67 marker results to come back from the Lab.)

During the past year, the Clan Gregor Project admitted its 200th member – a fine achievement for what is a relatively small clan. Now with 225 active participants, which makes us one of the largest clan groups, we have had a good number of citations in various journals.

What Characterises the Clan Gregor Project?
  1. We have tried to encourage adoption of the 37 marker test for identifying closer family relationships where this would be significant. As a result, we have an impressive array of results with benefits for both participants and larger scale studies trying to help sort out the ‘history and geography’ of genetic movement.

  2. We have encouraged some members to go further and have up to 67 markers tested. This has included what we believe to be the main MacGregor line and is beginning to help clarify the various sub families or ‘houses’ which form the MacGregor genealogy back into the Medieval period.

  3. Some of the MacGregors have undertaken SNP testing (of which more later) in an attempt to locate the likely geographical origins of the clan group (e.g. indigenous Scottish or Dalriadic Scots).
What have we found?

In brief...
  1. The MacGregors have predominantly one ancestor (the eponymous Gregor), but there is also a small unrelated Irish group includes Grierson and Grier, and who, it is believed, originate in the Irish kingly line of "Niall of the 9 Hostages."
  2. The aliases of Bain and Stirling were indeed originally MacGregor in certain families, and that the names have persisted to this day instead of MacGregor. Also, that at least one Campbell family is MacGregor, one Pressly, and one McNab.

  3. Some of the aliases – such as Grierson, Gregor, and Grier, have arisen. independently from MacGregor and in many cases the connection with the clan is by association not by blood.

  4. There are a number of MacGregors/McGregors whose ancestors adopted the name, through, no doubt having lived in the proximity of blood-related kin. However, some of these may be the result of non-paternity events which have had the effect of changing the DNA profile.

  5. There is a deeper ancestral connection which cannot really yet be satisfactorily explained – this group includes Magruder, Grieg, some Stirlings, some Gregorys, and possibly some McGehees. The connection here seems to be pre-surname adoption, but to lie within the period of the ‘Dark Ages’ during which clan affiliations were developing.
Why does DNA tell us this?

It has to be understood that when a male is DNA tested for genealogical purposes, the test is applied only to the Y chromosome. The Y chromosome is what makes males male. A father passes on the Y chromosome to his son and the son to his son – and so on. Anyone who descends from the same father will have the same Y chromosome. So if 400 years ago a man had 4 sons, each of those sons would receive the Y chromosome of their father and then those four sons would pass that same Y chromosome on to their (let’s say) 4 sons and then those 4 to their 4. This is assuming that 4 sons have 4 sons each (just for the sake of argument) although we know that families rarely work in such an orderly way, and also that, especially in earlier times, children did not all survive.

In this theoretical family there are:
Within a century, in this model, there would be 86 males all having the same Y chromosome DNA – except for small ‘copying’ errors which happen from time to time – these ‘copying’ errors being known as mutations. All these children should carry the same surname, unless they have been forced to adopt another surname as an alias, as happened to the MacGregors.

Women do not receive the Y chromosome and therefore, have to find a male with the surname MacGregor or one of the related names to do the DNA test on their behalf.

Women DO have DNA which can be tested. This is Mitochondrial DNA (MtDNA) which they got from their mother and which they passed on to all their children (including males) but males are unable to pass it on.

The update prior to this one explains what is revealed for each of the surnames found in the project, so it will not be repeated here. However, since then a number of individuals have had their DNA tested for 30 more markers. Most people in the group have had 25 or 37 markers tested but there are individuals who have had 67 markers tested, so a comment is needed about what has been found. The actual number scores can be found on the “Y Results” tab at http://www.familytreedna.com/public/MacGregor.

Chart 1 shows the current level of results. Most of the results belong to the R1b haplogroup – the haplogroup associated with the repopulation of Europe after the ice age (see Oppenheimer 2006), and the most common of haplogroups in northern Europe – as is reflected in the Clan Gregor Project. The two other groups often found are firstly Haplogroup I which is generally interpreted as Viking (only two 67 results so far – McWhannell and Greer – but the group is well represented in the Clan Gregor project being easily distinguished by the markers scores 8,9,8 on the 14, 15th and 16th markers). Secondly, we find R1a which originated in the Caucuses, but in the Clan Gregor project only the Orrs have so far fallen into that group.

Chart 1 - R1b Haplogroup (click to enlarge)

Although all the participants in the R1b group are ultimately related (i.e. thousands of years ago in some cases), only those contained within the group which circles round 2124 MacGregor (probably including 12436 and 28296 but possibly not 46397 McWhannell) come, we believe from ‘Gregor.’ The DNA profiles, and thus the chart, suggest that those who have tested for 67 markers belong broadly to the same family group of MacGregors, though because of their mutations, separation of the family units may date from the time of the proscription, and possibly not earlier in some cases. Although the Gregorys in this chart are all related to each other, they are only distantly related to the MacGregors, almost certainly NOT in the period of surnames (that from the 14th century) but not too distantly; which throws up an interesting possibility of a more ancient origin for the ‘Gregor’ name. Gregor means "shepherd" and could literally be a "shepherd of sheep," but also, in the Biblical sense, "a shepherd" (as in Pope Gregory). The McGehees belong to a similar outlying group, not related from the 14th century, but closer in time that all the others shown in the upper part of the chart. Again, notice the aliases – there is clearly a MacGregor who became a McNab and one who became a Stirling.

With the small number of 67 results, we are not showing members of the same family group as we do for the Gregorys. We would have expected more grouping round 2125, if, as believed, this is a Roro branch. It is likely that these groupings will develop as more 67 results are inputted. All the members of the R1b group at the top of the chart are unrelated to each other in the shorter time frame of surnames. We only have one 67 result for Orr – which is in haplogroup R1a – if this group all did 67 we would expect them to group together in a star shape like the main MacGregors showing family relatedness. The two members of the Viking group I are actually probably related to each other within a shorter time frame – possibly dating from 2000-1500 years ago.

We are hoping that scientific estimates on 67 markers will eventually enable us to be somewhat more specific as to date of separation but this refinement is not currently available since it requires a large group of 67 results allied to known genealogies to make the time estimate more reliable. We would expect to have more information on that in due course from FtDNA.

Chart 2 is not generated by the Clan Gregor Project, but is the current version of the R1b portion of the world haplogroups chart.

We have worked with a company called Ethnoancestry to see if it might be possible to identify, more exactly, the geographical origin of the Clan Gregor DNA line working with SNPs (short tandem repeats).

I am grateful to Bonnie Shrack for clarification of the difference between haplotype and haplogroup – and the significance of SNPs in the research. I include part of her e-mail to me on the subject to help understanding:

...There are two completely different things, defining haplogroups, and describing haplotypes. The haplotypes are made up of different series of Short Tandem Repeats, listed by the DYS number of the site where the repeat occurs – as seen in, for example, your test scores from FtDNA. But they never, ever, have defined haplogroups.

What happens is that scientists try to correlate the various haplotypes with haplogroups: we, all of us, are trying to figure out what haplogroup a particular haplotype probably belongs in. But having a certain haplotype can never guarantee a certain haplogroup. There are only correlations and probabilities.
[Since Bonnie wrote this to me, several companies now are able to confirm haplogroup, including FtDNA who show a confirmed haplogroup in green on their results chart.]

That's because Short Tandem Repeats, useful as they are for short-term genealogy, are not at all the thing to define a haplogroup, which is used instead for long-term questions: the migrations of ancient populations in human prehistory, thousands of years ago. So they are defined by something else – Single Nucleotide Polymorphisms (SNPs), and other similar kinds of mutations, all of which come into the category of Unique Event Polymorphisms (UEPs). These kinds of mutations are very rare, and we presume that once they have happened, they are never reversed.
At the moment, it has only been possible to confirm M269 on the chart for MacGregor – any mutation ‘downstream’ of that which ‘characterises’ MacGregors has not yet been found. However, the group which includes some Irish McGregors and others – those who are said to descent form Niall of the 9 Hostages – have been identified as lying in the subgroup M222, which is believed to be indigenous Irish, dating from the time when Ireland was first colonised, after the retreat of the ice (see Oppenheimer 2006).

Chart 2 - World Haplogroups Chart: R1b (click to enlarge)

If you are interested in further information, please go to http://www.familytreedna.com/ where there is a great deal of information about DNA and Genealogy. Instant updates – allied in many cases to information about the earliest ancestor of the participant will be found at http://www.familytreedna.com/public/MacGregor where there is also a map of the earliest known ancestor for most participants. Please wait for this to load as there is rather a lot of information because the Clan Gregor project is so big.

The summary of the Clan Gregor Project, given the update previous to this one, still represents an accurate picture of what we know for each of the family groups identified.

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