Can Genetics collaberate a claimed family tree.

Do they overlap on the same locations on the same chromosome(s)?

How could i or even the other 37 know or find out which of our chromosomes are relevant to the John Van Villiers line?

That's exactly what overlap analysis will help tell you.

If you have access to a chromosome browser for your 37 matches, record the stretches of DNA that overlap between you and your matches. You will begin to see patterns. Each stretch of DNA comes from one set of ancestors (or their descendants in a direct line to you). If Match A overlaps you on Chromosome 2 from 123456789 to 133456789 and Match B shares some of that overlap, then you can conclude that A and B are related to you through the same ancestral lineage.

I will bet, however, that your 37 matches don't all align that neatly and you have multiple common ancestors involved.

Geni provides "View Match Details" on my DNA matches. It then gives a little information such as "Overlap 8.5cM" and "Longest segment 13.9cM".I presume that tool is not sufficient?
Is is possible to access such a tool and would I not need access to the other persons raw data?

Private User -- every DNA match you have on Geni is a DNA match you have on FTDNA.
The info on "overlap" and "longest segment" is info taken from FTDNA .
FTDNA has a Chromosome Browser. So you can look there to see "the stretches of DNA that overlap between you and your matches"

Jason, my test is Autosomal and does match with know relatives on my mothers side. Whilst I agree with your comments about Alfred the Great, it is mainly that I wish to collaborate that my tree is indeed connected to John Van Villiers tree.

I have upgraded the FTDNA to include the chromosome browser. So I am looking for what exactly? Here is one match, I presume this is an exact match for me, that we share the same segment on the same chromosome?:- 6 8,154,254 19,360,281 16.85 4,685 So am I looking for other of my genetic matches on that same tree that also include at least some of that segment from number 6 chromosome in this case?

Further to the above, I understand all my DNA is in grey, the coloured parts represent the matching segment of one of my genetic matches. Am I now looking for all of my genetic matches on that tree, to have their coloured bars all in the same space on any given gene?

Karl David Wright - can you explain it to him?

The colored parts represent the overlaps between you and your match. The grey parts have no DNA in common between you and your match.

Get the chromosome overlap from one match and write it down, e.g. <match name> has overlaps on Chromosome <whatever> from <number> to <number>. Order these by chromosome and by starting overlap within the chromosome.

Then do the next match.

In fact, do ALL of your matches, or at least the ones whose tree you know. You'll have the beginnings then of a genome map

Ideally you'll need a way to learn whether the match is father's side or mother's side also, and ideally you should segregate them by father's or mother's side too. But let's put that aside for the moment and assume you just know this from the trees you have. Then, all of the matches from the same tree that overlap (meaning they include the same piece of DNA) come from the same ancestors. You just have to find out what those ancestors are. In some cases you'll have a pretty good idea already, so label those overlaps with those ancestors. Do other matches of yours also share that overlap? If they do, they've likely got the same common ancestors.

By the way, if you're using FamilyTreeDNA's chromosome browser, there IS a tool that, while not perfect, gives you a sense of whether a match is father's or mother's side. It's called "Matrix" and you can find it under "Autosomal DNA tools" from the menu. It will tell you if your DNA matches overlap EACH OTHER for real, not just because the numbers line up. But it's not a very good tool in my experience because those people you're checking may well be related to each other in other ways - or worse, the tool simply won't consider too short a match to be an overlap because that too can be misleading. But it's better than nothing.

GEDMatch has, and 23-and-me used to have, a much better way of doing this, which is a tool that directly allows you to compare two matches you have with each other and get the actual overlap they have. Then you can see if the overlap your matches has is consistent with the overlap you have with your matches.

Get DNA Painter, and map all of your closest matches, across testing platforms and in Gedmatch:

https://dnapainter.com/

You can do quite a bit with the free version and better understand ways you relate to your matches and how they relate to one another.

re: How could i or even the other 37 know or find out which of our chromosomes are relevant to the John Van Villiers line?

You're not, not really. When people post random nonsense about having found the Plantagenet or Pocahontas color segments in their DNA on Gedmatch or whatever, and claim to have identified them it is just that. Nonsense. Yet, those myths persists.

re: My question therefore is, can this be taken as confirmation of my connection to the John Van Villiers family tree, or can it be explained away that we are all related anyway if you go back in time far enough?

Which Sir John Van Villiers are you asking about proving a connection to? You're not going to prove a connection to anyone who lived in the 34th great grandparent distance with autosomal DNA. It is limited to a few generations, at best. Usually 5 o 6 generations, however sometimes "old bits" seem to stick around in certain populations.

What you can maybe sort out is a pattern of shared DNA among your matches. When those matches then have reasonably complete trees and known ancestry, you can then make reasonable assumptions about the location of the shared ancestry and who the common ancestor(s) may be.

You're not going to take your autosomal DNA test, snoop around and determine you are "royal". Sorry, but it doesn't work like that even if people insist it does.

Good luck!

For the last part--It only works that way if your autosomal DNA test conclusively shows something like King Charles is your father. :-) Needed to clarify, for obvious reasons!

You can have a bunch of DNA matches with people who are all claiming the same or similar things in trees, and be related for other reasons. It could be everyone has those ancestor(s) in the tree by chance, it could be accurate and also NOT your common ancestry, and it could be people seeing something royal/noble, getting excited and copy/pasting a spurious pedigree, which then was repeated by one cousin, and the rest followed.

The best proof is to get as many original sources for your immediate relatives, work out and keep doing this until you hit proven gateway ancestors. Even then you should be able and willing to find sources. Then you reasonably know your lines are solid. Then pick your best match and check their lines.

And yes, at the distances of 34th great grandparents and beyond? It is still always interesting to contemplate, but you're going to share those people with an amazing amount of cousins.

Thank you all. I did manage to work it out in the end.
My next question was to be, though I think Karrie has answered it already. These 37 DNA matches are via Sir John Villiers VII who Geni etc state is my 13th Great Grandfather, I understand that by just the seventh generation, an average of less than 1% DNA might still be present in my genome, and what is the chances of relatives branching off at that point having the same matching 1% as I? Never mind 14 generations. I think I am going to have to take the paper trail I have been presented with as the only evidence I will get.

Peter, that's not entirely true. 13 generations for Y-DNA is certainly not an unbelievable distance. But for autosomal DNA it would be unusual indeed to have any significant evidence of relationship from that far back. The limit in my experience is about 9th cousin; beyond that you don't really know whether an overlap is even real (there can be false positives with very short overlaps). There are rules you can follow if you are pursuing really deep autosomal relationships but they require lots of examples, e.g for 13 generations, you'd want 13 overlapping matches on the same stretch of DNA, and no less. Sounds like you have that but you haven't proved they're all overlapping, and you'd need to do that to have enough confirmation.

Thanks Karl. The link claimed by Family Search to this particular tree is via my mother. Can a Mitochondrial DNA test be as useful as the Y-DNA test you suggest?

Peter, are they direct lines?

mtDNA is useful if it is a direct line. I have taken one, and it is linked to my profile,so if it is useful/helpful you can click over and see how it populates relatives who also share the same direct maternal ancestry.

Y-DNA, same idea. My father passed away young, and being female I cannot test. BUT you can click on my son or my late husband if you like and see how the'r profiles have been populated by cousins here who are on the same direct paternal lines and have tested. (There is a bit of "confusion" because of people taking different levels of test, and something else possibly happening, just ignore that, you will get the idea though of the pattern if you look)

A good example I can give you with my son and his father: They're both related to King Richard, BUT you couldn't reliable use them to prove the remains found in the car park were his the same way they did with Michael Ibsen. Ibsen has a direct line to Anne of York. My son and his father jump around mother-son-mother-son, etc.

Michael Ibsen

Michael Ibsen → Joyce Muriel Ibsen (his mother) → Muriel Charlotte Folliot Brown (her mother) → Charlotte V. Stokes (her mother) → Charlotte Vansittart Frere (her mother) → Anne Vansittart Vansittart Neale (her mother) → Barbara Spooner (her mother) → Barbara Gough (her mother) → Barbara Calthorpe (her mother) → Barbara Yelverton (her mother) → Barbara Talbot (her mother) → Barbara Slingsby (her mother) → Barbara Belasyse (her mother) → Margaret Cholmeley (her mother) → Barbara Babthorpe (her mother) → Katherine Constable (her mother) → Anne Manners (her mother) → Anne Leger, Duchess of Exeter (her mother) → Richard III, King of England (her brother)

Forgot to show you the difference. You could not use mtDNA to prove this relationship to Richard:

James Elmer Thomas Welborn → James Penrod Welborn (his father) → James Elijah Thomas Welborn (his father) → Thomas Buchanan Welborn (his father) → William Hutcherson Welborn (his father) → James Dudley Welborn (his father) → Col. James Welborn, Jr. (his father) → James Welborn (his father) → Ann Wellborn (his mother) → Jane Ann Crabtree (her mother) → Grace Halstead (her mother) → Mary Courtenay (her mother) → John Stucley, of Affeton (her father) → Frances Stukeley (his mother) → Anthony Monke of Potheridge, Esq. (her father) → Frances Plantagenet (his mother) → Arthur Plantagenet, 1st Viscount Lisle (her father) → Edward IV of England (his father) → Richard III, King of England (his brother)

Hope this helps!

Thanks Karrie. Geni states, "Alfred the Great King of the Anglo-Saxons is your 34th Great Grandfather, However, the direct maternal link stops at my grandfather:- You → Audrey Charlton (your mother) → John Charlton (her father) → Elizabeth Jary Monk (his mother) → William Whittington Monk (her father) → William Monk (his father) → Sarah Monk (his mother) → Sarah Whittington (her mother) → Francis Bushby (her father) → Robert Bushby (his father) → Anne Bushby (his mother) → Alice Penfold (her mother) → Johane Olyver (her mother) → Dorothy Smythe (her mother) → Thomas Villiers (her father) → Sir John Villiers, VII (his father) → Sir John Van Villiers (his father) → Joan Bellers, Lady of Tilton (his mother) → Elizabeth Bellers (her mother) → Anthony Sutton alias de Howeby (her father) → Thomas Sutton (his father) → Lord John de Sutton II, Master of Dudley Castle (his father) → Margery de Somery, Baroness Dudley (his mother) → Roger de Somery, III (her father) → Roger de Somery, Baron Dudley (his father) → Margaret le Gras (his mother) → Maud FitzJohn Marshall (her mother) → John Marshall, I, of Rockley, le Mareschal (her father) → Gilbert FitzRobert Giffard, le Mareschal (sui uxoris) (his father) → Robert "the Norman" of Cheddar (his father) → Goisfrid du Bec, le Mareschal (his father) → Rollo / Rolf / Raoul du Bec, le Mareschal (his father) → Hawise (Heloise) de Guînes (his mother) → Elstrude, Countess of Flanders (her mother) → Arnulf I the Great, count of Flanders (her father)
→ Ælfthryth, countess of Flanders (his mother) → Alfred the Great, king of The Anglo-Saxons (her father)