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avalon
07-17-2016, 08:13 PM
I thought these were some interesting Welsh related snippets from recent preprint on blood pressure genes. http://biorxiv.org/content/early/2016/05/27/055855


No ancient samples were found to vary along the Welsh-specific axis, suggesting that the Welsh populations differ from the rest of the UK due to drift and not different levels of admixture.


Additionally, the lack of any ancient sample correlation with PC2 suggests that Welsh populations are not differentially admixed with any ancient population in our data set, and
likely underwent Welsh-specific genetic drift. We confirmed these findings by projecting pan-European POPRES samples onto the UK Biobank PCs noting that of the continental European populations, Russians (who have the most Steppe ancestry) lie on one side and Spanish and Italians (who have least) lie on the other side along PC1 and PC3, and that none of the continental European populations projected on to the same regions as the Welsh on PC2 and PC5.

I don't pretend to fully understand the process of genetic drift but my understanding is that it tends to occur in small populations which would fit with Wales, ie. a small country, mostly difficult terrain and lightly populated throughout history. Also, this explanation of drift might go some way to explaining the the results of the recent PoBI paper in which the Welsh showed a noticeable level of genetic separation from the rest of the UK.

AJL
07-18-2016, 01:15 AM
Interesting, I was musing a while back (http://www.anthrogenica.com/showthread.php?6827-Are-Welsh-people-a-restricted-gene-pool-autosomally) that there might be drift among Welsh people based on my autosomal matches. Thanks for that.

avalon
07-18-2016, 11:35 AM
Interesting, I was musing a while back (http://www.anthrogenica.com/showthread.php?6827-Are-Welsh-people-a-restricted-gene-pool-autosomally) that there might be drift among Welsh people based on my autosomal matches. Thanks for that.

Good observation, I hadn't seen that thread. I have heard a couple of people on this forum hint at some sort of Welsh drift but this is the first time I have seen it mentioned in a scientific paper.

JonikW
11-12-2016, 02:07 PM
Interesting, I was musing a while back (http://www.anthrogenica.com/showthread.php?6827-Are-Welsh-people-a-restricted-gene-pool-autosomally) that there might be drift among Welsh people based on my autosomal matches. Thanks for that.

I wonder whether this Welsh drift could have anything to do with why four of my 10 closest matches on 23andme match me on both my paternal and maternal sides. Or is that just down to the relatively small population? My mother was from the Valleys, while my paternal grandmother had roots in the Black Mountains. So they were from neighbouring populations rather than the same immediate area. Three of those matches are across three segments (0.32%, 0.31% and 0.25% shared) and the other is across two segments (0.45% shared). By way of comparison, a 0.59% match on three segments who matched only on my Mother's side turned out to have the same great, great grandfather as me, born at Llanfair Discoed, Monmouthshire, in the 1820s). Intriguing anyway...

jdean
11-12-2016, 04:12 PM
My mother is approximately 90% Welsh & 10% English

She picks up a lot more FF matches than my father who is 10% Welsh & 90% English and most of these folk have at least one generic Welsh name in their family tree.

Unfortunately I've never been able to help any of them save suggesting they likely have S. Wales ancestry with a bias to the SE because though I've managed to trace the surnames of 30 of her 32 3x great grandparents, and also place of birth for most of them, she only has 19 unique surnames plus I would imagine it very hard for most Americans to trace the origin (this side of the pond) of any ancestor who shared one or two of her Welsh surnames.

JohnHowellsTyrfro
11-12-2016, 04:32 PM
Worth remembering maybe that before the industrial revolution the population of Wales was only about 500,000 and that people in the more remote and agriculture-based communities probably didn't travel that far for the most part. I would guess that this would apply even more to the particularly remote places like Snowdonia.
It's a bit of a standing joke that if you meet a Welsh person for the first time, within 10 minutes they will have your life history and know how you are related. :) John

jdean
11-12-2016, 04:47 PM
Worth remembering maybe that before the industrial revolution the population of Wales was only about 500,000 and that people in the more remote and agriculture-based communities probably didn't travel that far for the most part. I would guess that this would apply even more to the particularly remote places like Snowdonia.
It's a bit of a standing joke that if you meet a Welsh person for the first time, within 10 minutes they will have your life history and know how you are related. :) John

Out of curiosity have you got a Jennifer Stedman in your matches ?

jdean
11-12-2016, 05:32 PM
Out of curiosity have you got a Jennifer Stedman in your matches ?

Ha : ))))

No worries, I can see you !!

'4th Cousin - Remote Cousin', now what would be the odds of that I wonder.

Pretty high I should imagine : )))))

JonikW
11-12-2016, 05:45 PM
Ha : ))))

No worries, I can see you !!

'4th Cousin - Remote Cousin', now what would be the odds of that I wonder.

Pretty high I should imagine : )))))

Or maybe not based on my experience:)

jdean
11-12-2016, 06:20 PM
Ha : ))))

No worries, I can see you !!

'4th Cousin - Remote Cousin', now what would be the odds of that I wonder.

Pretty high I should imagine : )))))

Sorry my mistake, this is the match with me, Mum's down as '5th Cousin - Remote Cousin' so presumably some of Dad's Welsh ancestry is kicking in to make us closer. He on the other hand isn't a match which again isn't too much of a surprise.

BTW Though Dad's genetic make up is 90% English and 10% Welsh he's also Welsh, he was born in Talywain like his father and his mother came from Merthyr

jdean
11-12-2016, 07:27 PM
Or maybe not based on my experience:)

We both have quite a lot of ancestors from the same corner of Wales, to be honest I doubt we are anywhere near as closely related as FF suggests but possibly share several ancestors from further back.

JohnHowellsTyrfro
11-12-2016, 08:55 PM
Out of curiosity have you got a Jennifer Stedman in your matches ?

I've got 1375 matches - maybe it shows the Welsh gene pool isn't very deep. :) John

JohnHowellsTyrfro
11-12-2016, 09:02 PM
Out of curiosity have you got a Jennifer Stedman in your matches ?

Like I said within 10 minutes a Welsh person will know your life history and how you are related. :) I wonder where the link is. I've Jones on the maternal and paternal side, but I've hit a wall on tracing them back further than a few generations. John

jdean
11-12-2016, 09:21 PM
I've got 1375 matches - maybe it shows the Welsh gene pool isn't very deep. :) John

If you click on advanced matches and pop Stedman into the top one (ie not ancestral name) you'll see both of me and Mum show up, but not my dad.

Dad's got 824 matches whilst Mum's got 1647, no idea how representative this is of English and Welsh FF results ?

However whist I've had limited success making connections with Dad's FF trying to do anything with Mum's is almost hopeless.

Q 'Can you give me more information on your Davies ancestry'

A 'Which one ?' : )

BTW I've also got the same problem with my MtDNA results, I've an exact match with a Canadian who's MDK MtDNA ancestor came from SE Wales whilst mine also comes from SE Wales, shouldn't be too hard ? Unfortunately his was a Jones from Cardiff and despite what the census says she didn't actually marry her 'husband' so I can't find out her father's first name which would have been a great help and whilst I know the maiden name and rough date of birth of mine and though she came from Crickhowell which would have been a tad smaller than Cardiff (even in 1793) the place was busting at the seams with Morgans (her maiden name) and I've a choice of about three individuals : )

jdean
11-12-2016, 09:28 PM
Like I said within 10 minutes a Welsh person will know your life history and how you are related. :) I wonder where the link is. I've Jones on the maternal and paternal side, but I've hit a wall on tracing them back further than a few generations. John

If you don't mind spending the money birth and marriage certificates are a great aid, birth certificates give the mother's maiden name whilst marriage certificates give the full name (normally) of the fathers of the bride and groom.

BTW the GPO have recently started issuing birth certificates as PDFs which are a few quid cheaper than the paper ones, haven't seen one yet but probably will sometime next week.

JohnHowellsTyrfro
11-12-2016, 10:18 PM
If you click on advanced matches and pop Stedman into the top one (ie not ancestral name) you'll see both of me and Mum show up, but not my dad.

Dad's got 824 matches whilst Mum's got 1647, no idea how representative this is of English and Welsh FF results ?

However whist I've had limited success making connections with Dad's FF trying to do anything with Mum's is almost hopeless.

Q 'Can you give me more information on your Davies ancestry'

A 'Which one ?' : )

BTW I've also got the same problem with my MtDNA results, I've an exact match with a Canadian who's MDK MtDNA ancestor came from SE Wales whilst mine also comes from SE Wales, shouldn't be too hard ? Unfortunately his was a Jones from Cardiff and despite what the census says she didn't actually marry her 'husband' so I can't find out her father's first name which would have been a great help and whilst I know the maiden name and rough date of birth of mine and though she came from Crickhowell which would have been a tad smaller than Cardiff (even in 1793) the place was busting at the seams with Morgans (her maiden name) and I've a choice of about three individuals : )

Crickhowell might actually be the registration district. One of my great grandmothers on my father's side was a Sabiah Jones (married name James which I found from the marriage certificate) who was born here in Nantyglo in 1835. I'm 99% sure her father was a shepherd/farmer Thomas Jones who lived in Llangattock and Llangynidr which is very close to Crickhowell. He was born in Llanafon Fawr which I believe is near Llandrindod Wells about 1795. On the marriage certificate her father Thomas Jones is described as a labourer which accounts for my 1% doubt whether they are the same person, but 2 men named Thomas Jones in generally the same area with a daughter named Sabiah born around the same time seems unlikely.
The odd thing here is that the Thomas Edwards who was a witness to the wedding would have either been Sabiah's son or the son of a sibling and was 10 years old. I haven't yet worked that one out. John

12554

jdean
11-13-2016, 11:01 AM
Crickhowell might actually be the registration district. One of my great grandmothers on my father's side was a Sabiah Jones (married name James which I found from the marriage certificate) who was born here in Nantyglo in 1835. I'm 99% sure her father was a shepherd/farmer Thomas Jones who lived in Llangattock and Llangynidr which is very close to Crickhowell. He was born in Llanafon Fawr which I believe is near Llandrindod Wells about 1795. On the marriage certificate her father Thomas Jones is described as a labourer which accounts for my 1% doubt whether they are the same person, but 2 men named Thomas Jones in generally the same area with a daughter named Sabiah born around the same time seems unlikely.
The odd thing here is that the Thomas Edwards who was a witness to the wedding would have either been Sabiah's son or the son of a sibling and was 10 years old. I haven't yet worked that one out. John

12554

AIH Mary Morgan (my 4 x G grandmother) did come from Llangattock but since it's literally next door to Crickhowell I put that down instead since more people know were it is : )

Even the Wiki page is entitled 'Llangattock (Crickhowell)'

jdean
11-13-2016, 11:17 AM
AIH Mary Morgan (my 4 x G grandmother) did come from Llangattock but since it's literally next door to Crickhowell I put that down instead since more people know were it is : )

Even the Wiki page is entitled 'Llangattock (Crickhowell)'

Tried to add a pic to the above post but couldn’t for some odd reason so here goes nothing

12566

avalon
11-13-2016, 11:19 AM
I wonder whether this Welsh drift could have anything to do with why four of my 10 closest matches on 23andme match me on both my paternal and maternal sides. Or is that just down to the relatively small population? My mother was from the Valleys, while my paternal grandmother had roots in the Black Mountains. So they were from neighbouring populations rather than the same immediate area. Three of those matches are across three segments (0.32%, 0.31% and 0.25% shared) and the other is across two segments (0.45% shared). By way of comparison, a 0.59% match on three segments who matched only on my Mother's side turned out to have the same great, great grandfather as me, born at Llanfair Discoed, Monmouthshire, in the 1820s). Intriguing anyway...

As I understand it, genetic drift is more likely in a small population, so I think the two things go hand in hand. Poster AJL did speculate that the Black Death may have been the key point in Welsh history as the small population was even further reduced and as John has said, prior to the Industrial revolution, Wales had always been very rural and sparsely populated, not many towns, other than those established by the Anglo-Normans, etc.

I would also make a comment about the genetic differences between North and South Wales -as per the PoBI,
Interestingly, based on this hierarchical clustering, north and south Wales are about as distinct genetically from each other as are central and southern England from northern England and Scotland

Difficult to pin point the genetic divergence between north and south Wales. The medieval sub-Kingdoms of Gwynedd and Dyfed, etc would be obvious explanations but then even in Roman times there were separate tribal entities in Wales. More likely, as we are talking about autosomalDNA, it's the last 500 years that are most significant.

JohnHowellsTyrfro
11-13-2016, 01:27 PM
Tried to add a pic to the above post but couldn’t for some odd reason so here goes nothing

12566

Can't see it unfortunately, I couldn't upload a photo either. I know where Llangatock is anyway. :) John

jdean
11-13-2016, 01:32 PM
Can't see it unfortunately, I couldn't upload a photo either. I know where Llangatock is anyway. :) John

I'm sure you do, it's only just up the road from you : )