The DNA of Archibald Frazer and Mary Lilly

The Recap

This blog follows up on my first blog about the autosomal DNA of the Frazers of Ireland. In that blog, I established that there were 2 Triangulation groups of Irish Frazer descendants. These matching groups were at Chromosome 1 and 12 and they represented the common ancestors of Archibald Frazer and Mary Lilly. Now, from what I’ve been able to gather, Archibald was born about 1743. My sister Heidi and Jane Fraser share a whopping 43.7 cM of DNA on Chromosome 1 from one of this 18th century couple who lived in Northern County Roscommon. That is a lot of DNA to come down through all that time.

Next I looked at Chromosome 12 Triangulation Group. Below is my sister’s chromosome browser. I put myself in for fun. It shows the large match I have with her. Below me is David who has an Irish Frazer ancestor named James that we showed must have a common ancestor with the rest of us due to Triangulation. Below him are Jane Fraser and Bill Richards.Frazer Chr12

What Did We Learn?

We learned that the 2 triangulation groups lead us to 2 different ancestors. We don’t know that they are Archibald Frazer and Mary Lilly for sure, but as they are the 2 closest common ancestors for this group, they are a good guess. The triangulation can’t tell us who the ancestors are. The paper research can, but we aren’t always sure we got the right information with missing vital records going back that far. Together, we have a good case that we are on the right track. And we have learned that Heidi and Jane are carrying around a lot of DNA around from 18th century Ireland people!

By the way, my genealogy web pages are at the link below. See under PART II: THE FRAZERS AND IRISH ANCESTORS; then look under the Archibald Line for Archibald Frazer and Mary Lilly:

We also learned that there are matches to these Triangulation Groups that don’t know that they are related to the Groups, but the DNA is showing that they are related in some way and share a common ancestor or ancestral pair. This should help others if they are looking for places to direct their family history research.

A Few Side Notes

You may have noticed that I didn’t inherit the Frazer DNA on Chromosome 1. Where did it go? I don’t know. That DNA lasted 200 years and then decided to drop out while my parents’ DNA was combining to form me. My father had that same DNA and gave it to my sister. That is a good reason why it helps to have more than one person in the family tested for DNA.

Other side note: See the red line above that represents my match with my sister. Does this mean that all the people I match from the beginning of the red line to the end are Frazer matches? Or are my Frazer matches only in the region at the right side of Chromosome 12 where the green is? I think that the entire red area are Frazer matches. I don’t mean that they all match Archibald and Mary. I mean that they should all match my Frazer Grandmother. I should have inherited roughly 25% of my DNA from her. In order to check this, I looked at a match I have with my father’s non-Frazer cousin – related on my Hartley side.

Gurney Chr 1-12

Well, look at that. Chromosome 12 shows no Hartley DNA in common with my father’s cousin and me. That leaves room for Frazer DNA. Also note that my match with my sister in red above was all one large segment. I will have to test it out, but it appears that all the matches I have that are on my father’s side where I also match my sister on Chromosome 12 should be related to my Frazer grandmother and her ancestors.

Well I think this blog has taught me something. I hope that it has been helpful to you.

Joel Hartley


Frazers in Ireland Autosomal DNA

Research for the family history of the Frazers in Ireland has been going on for at least 60 years. Recently DNA testing has been used to supplement that paper research. Documented Frazers in my line brings us back to 1749 where 3 Frazers were living in the northern part of County Roscommon in Aghrafinigan.

Down Survey Map Roscommon - Late 1650's
Down Survey Map Roscommon – Late 1650’s

The 3 Frazers were heads of households and their names were Archibald, James and the widow Mary. In the map above, the Townland is called Agharafinigan. In the Census of 1749, the Townland is called Ahrefinican.

My goals in using autosomal DNA are the following:

  1. Verify whether the 2 Frazer lines of Archibald and James are related
  2. Verify the existing paper genealogy
  3. Find new Irish Frazer relatives and confirm existing ones

I had originally thought that goal number 1 would require the use of YDNA testing which tests only the male line. I believe that the autosomal testing has already answered that question.

Goal #2 involves the analysis of the autosomal DNA using a process called triangulation. If there are 3 people who have tested who are not closely related and they all match each other on the same segment of a Chromosome, then they would have a common ancestor or ancestral couple. Here is an example of triangulation shown on a spreadsheet on Chromosome 1.

Chr Start Location End Location Centimorgans (cM) SNPs Match
1 205,319,654 237,417,351 43.7 8,565 HHM/Jane
1 222,994,591 230,852,310 8.4 2165 HHM/BR
1 223,053,736 230,852,310 8.4 2,140 BR/Jane

Here is what the Chromosome 1 match looks like from my sisters perspective as per

Frazer Chr1

On the right in yellow is my sister’s match to Jane and the blue on the right is her match to BR who is Bill Richards.

This represents 3 people who match each other on Chromosome #1. These 3 people all have traced their ancestry through the Archibald line. From what we can tell, they all have as a common couple:

Archibald Frazer b. about 1743 and

Mary Lilley

Now the interesting thing is that this couple is 7 generations away from my sister Heidi. However, based on the size of the match she has with Jane Fraser, interprets her common ancestors as being about 4 generations away. This could be because my sister and I have 3 different Frazers in our lineage. This would make the relationship seem closer than it really is.  Also I don’t know for sure if this match represents Archibald Frazer or Mary Lilley.

Another Triangulation Group

There is a similar Triangulation Group found in Chromosome 12. I sometimes find these Triangulation Groups in pairs. This makes sense as each one could represent one of the analogous ancestral couple. I expect this match represents the half of the couple that wasn’t represented in Chromosome 1, namely Archibald Frazer or Mary Lilley.  It looks a lot like the Chromosome 1 Group except it has a few more people in it.  It has as before, my sister Heidi, Jane Fraser and Bill Richards. In addition there is myself, an Irish Frazer descendant from Canada and at least 2 other people who likely don’t know they are related. I had contacted the Irish Frazer descendant from Canada early on. He has an ancestor named James Frazer who gave birth to a John Fraser in Enniskillen in County Fermanagh in 1832. So who is this James Frazer of Enniskillen?


Above is a representation of research that was done over 60 years ago. These are the sons of the the Archibald Frazer and Mary Lilley. Under Richard, there is a James with no other information. He would be a candidate for this James of Enniskillen.

Well I’m tired of writing. There is much more that can be addressed in future blogs. This represents 4 known Frazer descendants from the Archibald line that have tested. Plus one person who is unsure that he is from this line – although DNA shows he is related in some way. There are many others who have tested who are also from the James line and others who have had their DNA tested who may not know they are even related.

Joel Hartley