DNA Test Experiences and Implications

Anyone else out there think that this statement by the likes of ‘Ancestry’ is a load of hogwash? DNA sampling cannot tell you anything except where your ancestors ‘area’ lineage comes from, it certainly cannot tell you how to look or who to look for when searching for that ‘elusive’ relative from three or five generations ago (you have to have an idea of where in the first place).

Misplaced, misguided or plain misleading claims of both electronic (email etc.) and other media (print and television) are now becoming rife in this area. As a ‘self appointed’ family historian/ genealogist I am disappointed that this has not been addressed and that the likes of ‘Ancestry’ still utilize misleading advertising to game the gullible’.

Comments anyone?

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Ancestry’s DNA test is not accurate in many areas. If your female line is broken in any generation they cannot correctly identify where all your ancestors come from as they rely on the X chromosome to determine that so if you have a male after a female then you have lost 50% of the data, another male reduces this to nil for the chances of determining where your grandmother was from.

Sure it helps to look for hints but it is far from perfect. Though when you share your DNA they can match matriarchal lines if you get lucky and give you a link to other members of your lineage.

You pay a decent amount of money for the data and then have to give up many rights in regard to how that data is used, stored and shared.

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You need to read what Ancestry says about its DNA process and even augment what Ancestry is saying with other research about DNA sampling. It requires a bit of application as to what the DNA results are actually suggesting. It is somewhat complicated.

It is difficult to know when genes from a particular part of the world came into your gene stream. For example I have genes from Scandinavia. Are they recent in the family or did they come with the Vikings to Northumberland where lots of my ancestors lived? Because Ancestry gives my complete genome to me as part of the results, I can find out from a company that does that sort of analysis (but it costs).

The Ancestry DNA approach is similar to other similar DNA sampling services.

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Am continually amused by having a Jewish ancestor. Judaism is a religion, not a nationality.
My paternal grandfather was an Irish Roman Catholic, my paternal grandmother a Swedish Jewess, my maternal Grandfather an English Anglican, and my maternal grandmother a Scottish Baptist.
Wonder what my results would be: Celtic, Jewish, Anglo-Saxon, Pict?

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You might find this opinion interesting or not.

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A Jew might disagree that it is only a religion. The person could argue that they have a distinct ethnic background that defines them both religiously and physically from others as at least one their forebears came from a distinct tribe in a particular region unless they had joined the Jewish faith as a “Gentile”.

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But Judaism is more than just a religion, it’s also a culture. And as such it has an ethnic element. Jews can of course live anywhere, just like people from any other race, but the ethnicity is originally North African.

As an adopted person, I certainly have found that Ancestry (and similar sites) have been able to tell me ‘who I really am’ more than the false birth certificate I was issued with on adoption. I know that a lot of adopted people have been able to find their family and ancestry on these sites, so that wording is very relevant for those who don’t have Biological Privilege.

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I have used the Genographic project from National Geographic. They partner with Family tree DNA and have a better data base. My brother in laws have used both and have very different results. I think that the Ancestry results are very much guess work. Particularly for any analysis less than a thousand years.

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Gday Ferij. I am wondering what you mean by “Particularly for any analysis less than a thousand years.” I thought these systems compared your genetic markers to those common in various population groups and so gave an estimate of which population(s) your ancestors came from. What has that got to do with 1000 years?

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As it happens, my day job involves quite a bit of this for tree breeding.

these systems compared your genetic markers to those common in various population groups

We do exactly as you have suggested, both for identification of provenance (tracing back to specific population groups or “races”) and identification of specific parents, grandparents etc etc.

For identification of provenance you need few markers, as genotyping groups of populations will produce reliably fixed and diverse results at certain points. For humans, these informative points are well-known and publicly available in many research papers.

For identification of specific parents, grandparents etc you need quite a few markers (which increases cost for testing and analysis time for data crunching) and it can be tough to reliably determine with very high accuracy. We typically use 3000 markers and produce a likelihood, which is good enough for tree breeding purposes. I haven’t spent much looking at the specifics of the AncestryDNA test. But it appears to be a simple provenance analysis. Looking at the markers you have, seeing which ones match to ethnic origins.

This is why the AncestoryDNA test is $149, some are as low as $89, and a paternal DNA test is around $300 for a cheap one.I’m not sure how many markers they screen for. You’ll see about $500+ for a court approved one.

We charge ~$30 per test for volume customers.

Edit: just scrolled down on the AncestoryDNA test. They claim:

Your DNA will be analyzed at more than 700,000 genetic markers.

Which means they’re probably using a chip-based solution with fairly low coverage (they don’t read and re-reach each marker point to make sure it’s producing a highly accurate result for each individual marker). There wouldn’t need to be high accuracy for each individual marker to make a good estimation of provenance.

As an aside:
We use a sequencing based genotyping system. Good for flexibility and cost. We read & re-read each of the 3000 markers we test for about 25-30 times. We need high accuracy when we’re using markers to make predictions about a tree’s potential performance.

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Hi syncretic! The shorter the time scale the less chance for mutations to occur that can be used as distinguishing markers. However the more data that can be gathered the more likely that population variations will become apparent. To my knowledge, Ancestry don’t have as big a database as Genographic/ Familytree. It must also be realised that we are in the early stages of these studies and only a small fraction of the Human genome has been studied for these markers. Much of what is proposed at present may very well be wrong or simply misinterpreted due to insufficient evidence.

Ferji, I don’t think you understand how this works.

The markers examined are those that do not change. The transmission of markers through your ancestors’ line is what gives the estimate of who your ancestors were not the mutations that may have occurred along the way. It is very rare for a mutation to be clearly identified to a given time much less an individual. Consider the case of hemophilia in the royal houses of Europe. Victoria passed it on to many of her descendants but despite the stud books of the royals being meticulously kept as far as I know the origin of that mutation has never been found with any certainty.

From the Ancestry website:
"For example, some Genetic Communities trace their roots back to groups of people who were isolated geographically. Mountains, rivers, lack of roads, or other barriers made it likely that each new generation would marry someone who lived close to home. Others have their roots in a group of people who typically married others of the same religion or ethnic group. In each case, over time these groups came to share a significant amount of DNA. Their modern-day descendants who inherited some of that DNA make up Genetic Communities. "

We’ve used the Ancestry DNA service this year. It’s true I was a little disappointed in the level of detail. The overall results were spot on for the research we have for all our family lines going back 200yrs+. I can’t be critical of that or the advertising.

The real benefit of participating or for some of us a risk is that the results are available to assist us to locate others with related DNA markers and hence possible members of our extended family. We have had at least one such result. It’s true there was an unexpected birth and adoption that had broken the chain. However it has enabled another family to learn more of one side of their family and seek images etc. This is a good thing!

I was a little surprised that they did not distinguish in more detail the DNA that I have provided at the level of the ancient tribes of Great Britain - but as others have already indicated this is a complex and expensive task. I doubt I will get our Croft back near Skye no matter what detail the DNA reveals.

I admin 3 kits for Ancestry and two for Family Trees DNA and I for 23 and Me. For two people we did our DNA for ethnicity results and to find relatives. One person with UK heritage has found many matches and one with Dutch heritage not so many matches. The other person is looking for unknown paternal ancestors and has found many 3rd - 4th cousins and that persons ethnicity has been very accurate. So the money spent has been worth it . Sometimes when looking for an unknown person DNA will be the only way to find that person

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I not along ago i looked into getting a DNA test done to check out my ancestry. Upon reading the fine print in the terms and conditions I discovered that if i clicked ‘i agree’ that the prominent company doing the test could ‘share’ my DNA results with pretty much any one they liked. Not really liking the idea of my personal info floating around out there in the corporatesphere I declined. Anyone checked this out and know of any companies do the the tests confidentially?

The test I looked at was by a company that advertised ancestry research services on TV. You probably would have seen their ads.

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Was that a full test, or just a partial to test for genes related to some diseases? How expensive is it to have done now?

The last thing I’d want is for my DNA to be sold to some multinational biochemical company to own!

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Agreed - doubly so if the DNA is permanently linked to your name/etc …

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I think one of our fundamental rights is the very right to our own privacy . If I was going to explain my ancestry to another party it would be me by my own volition to do that . It is my right . /
There would be other DNA facilities out there that would test you and not pass your details on . They would probably charge a higher fee because they are not supplementing their income by passing personal details onto 3rd parties . /
Unfortunately we seem to live in a world where the right to privacy seems to be being " Thrown out the door " Well it seems to be heading that way .

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Thanks for flagging this @kodez23, that’s definitely an interesting one. I’ll be sure to pass the tip onto my colleagues in investigations.

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