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Messages - phil57

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I think the percentages the two of us are referring to might be two different things? Yours seem to be saying the percentage of probability of X relationship. The percentages I am talking about is the total percentage of DNA that we share.

The only certainty in percentages of DNA shared is between parents and their children. All other relationships are variable, to the extents indicated by the DNA Painter tool and similar charts. You also have to beware of outliers - individuals who might share a substantially higher or lower percentage of DNA than the normal range for any given relationship.

DNA Painter expressed the probability of particular relationships for the percentage or amount of DNA shared between individuals. It is a handy tool, but it is important to recognise that just because a certain relationship has the highest probability, it doesn't follow that it is necessarily the correct relationship for your circumstances.

You have to do the traditional research, look at the probabilities of relationships between individuals you have researched being related in various ways, and compare those relationships with the probabilities suggested by tools such as DNA Painter. Nothing is certain, and trying to establish a specific relationship purely by the amount of DNA shared is fraught with difficulty.

I can give a couple of personal examples. My brother has a relatively low share of 59 cM with a 2nd cousin.

We have three 2C1Rs, all siblings born of the same parents. My shared matches with them range from 23 cM to 147 cM.

Ancestral Family Tree DNA Testing / Re: DNA results donít match my research.
« on: Monday 16 May 22 18:52 BST (UK)  »
I can only suggest reading some of Ancestry's own documentation.

I can give you a perfect example of a meaningless allocation by Ancestry.

My ancestors, certainly within the last 300 years, were all born in the British Isles. My GGF on my maternal side was born in Montgomeryshire. He led a fairly colourful life, having had six wives and other extra marital relationships from which numerous offspring resulted. My GGM, his fifth wife, died of complications of pregnancy shortly after the birth of my GM. She had an older brother who never had children, so all of the numerous offspring of my GGF apart from my GM and her brother, are only half-relations to me. Quite a number of the children from his earlier relationships emigrated to the United States, and have also bred profusely, with the result that my brother and I have many DNA matches at fairly high levels for the relationships involved, to those half-cousins current descendants.

The result is, according to Ancestry, that my brother and I are in part descended from an Ohio, East Kentucky and Indiana community!

Bunkum, my direct ancestors have never been anywhere near the USA, apart from said GGF, who spent a few months in Texas visiting a couple of his emigree sons.

Ancestral Family Tree DNA Testing / Re: DNA results donít match my research.
« on: Monday 16 May 22 18:17 BST (UK)  »
I think we are in agreement, Phil  :D

Yep :)

Ancestral Family Tree DNA Testing / Re: DNA results donít match my research.
« on: Monday 16 May 22 18:03 BST (UK)  »
Ancestry allocate ethnicities according to markers in your DNA which they consider identical to their self-defined reference populations. Those "ethnicities" do not even relate directly to you - they are "matching" groups of people from more than 500 years ago; so attempting to use them to infer the place that your grandparents, great grandparents or even Gx6 grandparents lived is completely wrong. As Ancestry explain themselves, if you have been allocated a percentage of Scottish ethnicity, for instance, it should not be taken to mean that your ancestors were from Scotland. It means that your ancestors had markers in their DNA which can be most commonly found in people who live in Scotland today. But those Scots came from elsewhere, along with others of similar origin who didn't actually settle in Scotland, but who will be ascribed Scottish ethnicity by Ancestry as a result.

You may think that your DNA communities are more accurate. They are intended by Ancestry to reflect the locations that your ancestors lived in, in the more recent past. BUT they aren't allocated from evidence found in your DNA as a result of a laboratory examination!!! They are determined by an algorithm from your Ancestry DNA matches and common locations entered in your and their family trees, in a similar way to the Thrulines algorithm that suggests relationships, and they are therefore just as reliant on the accuracy - or otherwise - of members' family trees.

So ethnicity, whilst being an attractive marketing tool for selling DNA tests, is really of minimal use or reference for finding or identifying relatives within a more recent time frame (c. within the last 500 years).

I use a custom fact in Family Historian to record details of each DNA match against the individual concerned, including the match length, number of segments, length of largest segment, test company, username and account link, MRCA, etc. That information can all be pulled out and displayed or manipulated in custom queries.

Individuals who are DNA matches and MRCAs can be indicated as such on tree diagrams, and FH can also show connecting routes between matched individuals on the diagrams. This can pick up where more than one route exists between individuals, e.g. due to pedigree collapse, which might otherwise be missed. It works for me.

You will also find anomalies because, as far as I'm aware, no single company samples 100% of your DNA for consumer market autosomal testing. One test might include lengths that another may miss, and vice versa. GEDmatch allows you to create a superkit, by merging tests from different companies. Interestingly, this can often lower the length of your matches because it allows some string lengths to be either matched or ruled out, where they may instead have been inferred as false matches in the results of a single test.

Ancestral Family Tree DNA Testing / Re: Can thru lines help ?
« on: Wednesday 04 May 22 16:04 BST (UK)  »
As above, thrulines mean absolutely nothing other than that Ancestry's algorithm has detected possible relationships to a line in your tree, based on information from other user trees. The information in those trees may be wrong and always needs checking thoroughly by doing your own research into the proposed lines before accepting any of it, in my experience. Conversely, other trees may be correct and yours may be wrong. Either way, it all needs to be checked for accuracy, as Ancestry have no way of checking that any proposed thru lines are correct, only that they appear to match a software calculation that has recognised potential relationship patterns between two or more member trees.

I have no thrulines to one of my Great Grandfathers. The reason is that every other member tree on Ancestry in which he appears, wrongly identifies him as a different man with the same name, although born into a different family in the same year and location. Consequently the ancestral line is completely wrong and will never match against my tree through Ancestry's algorithm. How do I know that all the other trees are wrong and mine is correct? Because I have copies of his marriage certificate and the birth certificates for all of his children, which between them contain information that differentiates the two similarly named individuals and makes it certain which is correct. One or several other trees have been constructed without fully researching the two people concerned, and the incorrect lineage has spread through the common practice of people accepting information from other member trees without making any checks!

Annie, apologies if you already know this and have other reasons for wanting to take a second test, but are you aware that you can download a copy of your raw DNA data file from Ancestry, and many other testing companies will let you upload it (transfer in) to their databases for matching? Ancestry are one of the few that don't allow transfers in from other companies, but nearly, if not all of the companies who allow transfers in will accept Ancestry DNA files.

I have transferred my Ancestry test to My Heritage, LivingDNA/FindMyPast, FTDNA and Gedmatch.

The Common Room / Re: Probate search
« on: Monday 25 April 22 16:49 BST (UK)  »
Several post 1995 wills that I have recently ordered were delivered instantly; that is to say they were available for download in the "My Orders" list as soon as I had been redirected back to the HMCTS website after making the payment.

Another, older will was also available instantly after making payment, but a copy of the associated grant took a few more days to arrive.

I recently ordered one from 1875, for which I had to enter the folio number, and expected that it might take a week or more to retrieve, but it was available a couple of days later.

Interestingly, for the ones that became available instantly, I didn't get an email informing me that they were ready, but whether the fact that I had downloaded them straight away caused the system to cancel an email notification I can't say.

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