Why according to Irish DNA Atlas is the "North Leinster/Ulster" Irish cluster the furthest from

[Sikeliot]

Britain genetically?

I would never expect this, because Ulster is the province of Ireland where the British have had the greatest influence on the population, having transplanted many Scottish and English settlers.

I think North Leinster/Ulster cluster must be the indigenous Catholic Irish, who may have remained more segregated from the British genetically whereas in other parts of Ireland -- even SW Ireland like Kerry -- the British were less numerous and could more peacefully be absorbed into the Irish population.


"The Ulster cluster itself shows the greatest genetic distance from Britain, in both our PCA and Fst analysis, despite its geographic proximity to Britain. Given that we have identified groups within the north of Ireland that do have genetic links to Britain, i.e. the N Ireland clusters, Ulster most likely represents individuals of ‘Gaelic’ ancestry that have remained genetically isolated from Britain – which reflects the demographic and political history of the region."


Fst differences between "England I" and all the Irish clusters are as follows, from smallest to largest difference:

Dublin: 0.00073
Leinster: 0.00081
Central Ireland: 0.00083
North Munster: 0.00101
Connacht: 0.00107
South Munster: 0.00131
Ulster: 0.00145


And a similar pattern holds for most of England and Scotland.

[Dick]

Political Propaganda Probably.

[Sikeliot]

Political Propaganda Probably.

You don't get what I am saying.

The study is saying that while the "British" population in Ulster is genetically close to Northern England and Scotland, the "Irish" population in Ulster is further genetically from Britain than people anywhere else in Ireland, meaning that Irish from places like Galway, Kerry, Limerick, Dublin are more "British" genetically than those Irish in Ulster who are likely to be Catholic and Irish in identity. This is the implication.

So... why is this?

[Dick]

You don't get what I am saying.

The study is saying that while the "British" population in Ulster is genetically close to Northern England and Scotland, the "Irish" population in Ulster is further genetically from Britain than people anywhere else in Ireland, meaning that Irish from places like Galway, Kerry, Limerick, Dublin are more "British" genetically than those Irish in Ulster who are likely to be Catholic and Irish in identity. This is the implication.

So... why is this?

Ask Grace O'Malley

[J. Ketch]

It probably goes back to Norman times and the integration of the 'Old English' (more Cambro-Normans than English though) into the Irish population, which was more substantial than whatever British input there is post-plantation since the 1600s.

https://upload.wikimedia.org/wikipedia/commons/2/22/Www.wesleyjohnston.com-users-ireland-maps-historical-map1300.gif

[Sikeliot]

It probably goes back to Norman times and the integration of the 'Old English' (more Cambro-Normans than English though) into the Irish population, which was more substantial than whatever British input there is post-plantation since the 1600s.

https://upload.wikimedia.org/wikipedia/commons/2/22/Www.wesleyjohnston.com-users-ireland-maps-historical-map1300.gif

So you think the land there that is in green, avoided a demographically significant population transfer of Normans from England who were absorbed into the Irish population?

Apparently, before the plantations in Ulster, Ulster was the least Anglicized region.

[J. Ketch]

So you think the land there that is in green, avoided a demographically significant population transfer of Normans from England who were absorbed into the Irish population?

Apparently, before the plantations in Ulster, Ulster was the least Anglicized region.
I think it's as good a reason as any. As you alluded to, the British settlement of Ireland since the 1600s has been highly segregated from the native population, that wasn't the case for the Normans, who as the saying goes became more Irish than the Irish themselves, and you can see it in how many Irish surnames today are of Norman origin. Also the population was so much smaller then, any influx of foreigners would have a greater impact.

[Sikeliot]

I think it's as good a reason as any. As you alluded to, the British settlement of Ireland since the 1600s has been highly segregated from the native population, that wasn't the case for the Normans, who as the saying goes became more Irish than the Irish themselves, and you can see it in how many Irish surnames today are of Norman origin. Also the population was so much smaller then, any influx of foreigners would have a greater impact.

The Norman settlement could explain why Connacht (which had a quite heavy Norman settlement) is closer to Britain despite being in western Ireland and not subject to later British arrivals.

Also, Viking input could play a part. Norwegian Viking input would have been quite genetically close to the Anglo-Saxons in England, who were mostly from Denmark and northern Germany. Apparently, any and all Viking input in Ulster was brought indirectly from the Scots.

[Rieder]

It is interesting to compare the Y-DNA halpogroup distribution in Ireland with the Autosomal results you posted.

The distribution of R1b in Ireland follows a different (and arguably more expected) distribution.

Connacht(98.3)>Munster(94.6)>Ulster(81.1)>Leinster(73.3)

I don't know the distribution between Catholics and Protestants in Ulster, but I doubt it is reasonable to assume that the frequency of r1b among Ulster Catholics would be as high as Connacht.

Also, you should consider that the differences may not nessercily be related to actual British Ancestry, but also the admixture of older groups.

As you are well aware Scandinavian admixture is more significant in Britain on average than Ireland.
The Norse people that settled in Ireland were concentrated in Leinster, with Dublin being a major center.

And then there is the Norman influence too.

That may very well explain why Leinster and Dublin are closest to British people.
I1 halpogroup is relatively common in Leinster, but very seldom in Connacht and that is explained by the distribution of Norse settlement

On the other hand Ulster was traditionally more Isolated. This isolation goes back far, so you have to look back to see the whole picture.

[Sikeliot]

It is interesting to compare the Y-DNA halpogroup distribution in Ireland with the Autosomal results you posted.

The distribution of R1b in Ireland follows a different (and arguably more expected) distribution.

Connacht(98.3)>Munster(94.6)>Ulster(81.1)>Leinster(73.3)

I don't know the distribution between Catholics and Protestants in Ulster, but I doubt it is reasonable to assume that the frequency of r1b among Ulster Catholics would be as high as Connacht.

Also, you should consider that the differences may not nessercily be related to actual British Ancestry, but also the admixture of older groups.

As you are well aware Scandinavian admixture is more significant in Britain on average than Ireland.
The Norse people that settled in Ireland were concentrated in Leinster, with Dublin being a major center.

That may very well explain why Leinster and Dublin are closest to British people.
I1 halpogroup is relatively common in Leinster, but very seldom in Connacht and that is explained by the distribution of Norse settlement

On the other hand Ulster was traditionally more Isolated. This isolation goes back far, so you have to look back to see the whole picture.

English input in Ireland, apart from in Northern Ireland Protestants, should be highest in places like Dublin, Kilkenny, and Wexford.

Autosomally, Connacht is somewhere intermediate between Leinster and the more 'isolated' groups like the Gaelic Ulster cluster and some parts of Munster. Despite the high frequency of haplogroup R1b in Connacht, the autosomal record, which is more accurate in determining genetic placement, shows something else. Selective pressures may have altered the y-dna record, and we also have not looked at the maternal side, as some of what we are seeing autosomally might be reflected in the maternal haplogroup pool.

[Sikeliot]

Other opinions on this?

Anyway I think both studies -- Insular Celtic paper and the Irish DNA Atlas -- have shown y-dna to be an inaccurate indicator of Irish autosomal DNA. Connacht is not, in either study, the least British part of Ireland.

[Sikeliot]

Other thoughts on this?

[Rieder]

Other opinions on this?

Anyway I think both studies -- Insular Celtic paper and the Irish DNA Atlas -- have shown y-dna to be an inaccurate indicator of Irish autosomal DNA. Connacht is not, in either study, the least British part of Ireland.

Not only does Y-dna appear to be an inaccurate indicator of Irish autosomal DNA, but mtDNA may not be any more accurate.

There is less variation in mtDNA frequencies in the British Isles than there is Y-DNA variation (not that there is particularity great Y-DNA variation either).

Between Scotland and England for instance, there is less than 1% variation for for most mtDNA halpogroups and the variation for no halpogroup exceeds 5% (this is based on sources from Eupedia).

I am not sure that mtDNA would correlate any better with autosomal DNA in the case of the Irish, nor do I have any evidence to suggest that mtDNA generally correlates with autosomal DNA any better than Y-DNA does.

I would like to know your thoughts on how Irish mtDNA might fit into all of this.

[Grace O'Malley]

Not only does Y-dna appear to be an inaccurate indicator of Irish autosomal DNA, but mtDNA may not be any more accurate.

There is less variation in mtDNA frequencies in the British Isles than there is Y-DNA variation (not that there is particularity great Y-DNA variation either).

Between Scotland and England for instance, there is less than 1% variation for for most mtDNA halpogroups and the variation for no halpogroup exceeds 5% (this is based on sources from Eupedia).

I am not sure that mtDNA would correlate any better with autosomal DNA in the case of the Irish, nor do I have any evidence to suggest that mtDNA generally correlates with autosomal DNA any better than Y-DNA does.

I would like to know your thoughts on how Irish mtDNA might fit into all of this.

There is a lot more variety of mtdna in places like Ireland vs ydna. Ydna in Ireland appears to have very much gone under some sort of founder effect and also the Bronze Age type appears to have been mostly R1b-L21. There is a paper coming out by Lara Cassidy which looks at genomes from different periods in Ireland which should be very interesting. I have the FMS done on my mtdna and I have a full match in Ireland but my 1 step matches are in Norway, Sweden and the Russian Federation so I'm not sure whether this was from women from Ireland going in that direction or the other way around.

With the clusters the distances make sense to me as the more extreme areas i.e. South Munster and parts of Ulster were more isolated. Ulster for instance was a Gaelic holdout the longest in Ireland which was why the British did the largest plantations there to kill 2 birds with one stone i.e. have a loyal stock and get rid of the rebellious types there.

[Sikeliot]

With the clusters the distances make sense to me as the more extreme areas i.e. South Munster and parts of Ulster were more isolated. Ulster for instance was a Gaelic holdout the longest in Ireland which was why the British did the largest plantations there to kill 2 birds with one stone i.e. have a loyal stock and get rid of the rebellious types there.

So maybe it makes less sense to divide Ireland genetically by east and west then, as places like Clare, Connacht, and the inland west might be closer genetically to Leinster (thinking of North Munster and Connacht clusters here, and that "Central Ireland" extends also from Leinster to Connacht and likely captures anyone not fitting squarely into the other 2 clusters).

[Graham]

Ulster was the O'Neil stronghold that had a stronger Gaelic identity.

A small quote from wikipedia for example.


Once the MacLaughlins were defeated, the O'Neills spread out and slowly dominated the other client clans across Ulster and the other Irish kingdoms. They used the disruption of the Norman invasion of Ireland in 1169 to their benefit and were able to consolidate their hold on the western half of Ulster.

The Bruce Invasion of Ireland devastated the Norman Earldom of Ulster, which held sway over eastern Ulster and most of its north coast all the way to Derry. Its collapse in 1333 allowed a branch of the O'Neills that had been on good terms with the Normans, the Clandeboy O'Neills, to step into the power vacuum and take control over large parts of eastern Ulster.

[Rieder]

There is a lot more variety of mtdna in places like Ireland vs ydna. Ydna in Ireland appears to have very much gone under some sort of founder effect and also the Bronze Age type appears to have been mostly R1b-L21. There is a paper coming out by Lara Cassidy which looks at genomes from different periods in Ireland which should be very interesting. I have the FMS done on my mtdna and I have a full match in Ireland but my 1 step matches are in Norway, Sweden and the Russian Federation so I'm not sure whether this was from women from Ireland going in that direction or the other way around.

With the clusters the distances make sense to me as the more extreme areas i.e. South Munster and parts of Ulster were more isolated. Ulster for instance was a Gaelic holdout the longest in Ireland which was why the British did the largest plantations there to kill 2 birds with one stone i.e. have a loyal stock and get rid of the rebellious types there.

In terms of frequency Ireland and England differ more on R1b than they do on mtDNA halpogroup H (most common halpogroup in Britsh Isles).

This is however, perfectly reasonable considering that H halpogroup is found at similar frequencies over large areas of Western Europe and has much less regional variation than R1b.

Your mtDNA results ( close to Russia, Norway, Sweeden) are reasonable because mtDNA is much less regionalized than Y-DNA, there is much less mtDNA variation between different regions of Europe than their is Y-DNA.

The mtDNA of Europeans is closer together than the Y-DNA is.

With this, I don’t think mtDNA would correlate with autosomal DNA than Y-DNA would.

[Grace O'Malley]

In terms of frequency Ireland and England differ more on R1b than they do on mtDNA halpogroup H (most common halpogroup in Britsh Isles).

This is however, perfectly reasonable considering that H halpogroup is found at similar frequencies over large areas of Western Europe and has much less regional variation than R1b.

Your mtDNA results ( close to Russia, Norway, Sweeden) are reasonable because mtDNA is much less regionalized than Y-DNA, there is much less mtDNA variation between different regions of Europe than their is Y-DNA.

The mtDNA of Europeans is closer together than the Y-DNA is.

With this, I don’t think mtDNA would correlate with autosomal DNA than Y-DNA would.

I agree that mtdna doesn't correlate with autosomal nor does ynda necessarily but there is a lot of variety of mtdna in both Britain and Ireland as in most countries.

In terms of maternal mitochondrial DNA (mtDNA), about 38.5% of Irish people carry mtDNA haplogroup H (of whom 11% are in H1 and H3), 13% carry U (of whom 2% are in U2, 0.5% are in U3, 2.5% are in U4, and 6% are in U5), 12% carry T, 11% carry K, and 10% carry J. Several others are encountered at smaller frequencies: 4% in HV0 and V, 3% in I, 2.5% in W, 1.5% in X2, and 4.5% in other(s).

http://www.khazaria.com/genetics/irish.html