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Post by DADDY O on Apr 1, 2017 11:46:49 GMT
DNA "evidence" is not evidence, it is an exhibit. Evidence can only be adduced by cross examination. And in a legal sense of the term, that is true. To provide "evidence" of a crime, a prosecutor will determine the DNA found on a victim and then attempt to compare if with the DNA of a "suspect". If they match (within reasonable parameters) then the "Evidence" can be cross examined to attempt to validate or refute it. Juries then decide if the evidence is believable or not.
Usually it is..................but then, we always have the O.J. Simpson factor, where the size of a pair of leather gloves (perhaps shrunken over time and abuse) is a more determining factor than the DNA was.
Go figure.
However, the DNA from a $139 Ancestry.com test kit is taken and then compared with a database of other Ancestry.com members who have submitted the test. Thus, and assuming the DNA test is performed well, you are comparing your DNA with the DNA of a database and then "assumptions" are made as to who you might be related to on the other side of the world....and all of this has happened within our "modern era" because no database exists for the DNA of anyone who lived more than.....say 25 years ago......or in Ancestry.com's database ~ 10 years ago.
If you want to test the system for accuracy, have a close relative of yours who lives on the other side of the world, submit their DNA to Ancestry and see what analysis you get. After all, "No one has closer DNA ties to you than your own children/brothers/sisters......etc.".
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Post by sherri on Apr 1, 2017 22:40:50 GMT
I possibly haven't explained it all very well daddyo. But the DNA analysis done by Ancestry would pick up a close relative in a heartbeat and also tell you the most likely relationship. For example, a parent will have what they call one degree of separation but a sibling or grandparent will have 2 degrees of separation & so it continues. The further away, the more separation, as you would expect.
So if you had DNA done & a sibling of yours had DNA done independently (under their own account on ancestry) and you never put up a tree or anything, your DNA results would still come up as 'immediate family-most likely a sibling or grandparent'
The DNA results do NOT try to link you to long dead people by saying you have a DNA match with them. What happened is ancestry analysed DNA from groups of people currently living in different areas, people who claimed to have family that had been in the region for generations. Then what ancestry does is if you get tested, it tells you what DNA areas you currently have most in common with.
The main way it helps though is this: I'll see if I can show you a screenshot. I know it is small, just double click & it will show full size. Have a look at the 3rd match there. Cawoods. It shows I have a genetic match with cawoods. I had never heard of that account. Cawoods contacted me as she had me in her list of matches too of course. We worked out where the connection is (in emails back & forth)-it is in the Coath line-my father's father's mother's line. Cawood was able to supply me with information about some of the people in that line & photos. Info I had not had before. Cawoods is in another state. Ancestry would not have known of our connection as when you send in a sample, it is by number code only. You could assign any name at all to it. The system doesn't know whose DNA it is.
Ancestry does a great job of matching DNA from current participants & that is mainly what it is about.
The bit about guessing your ancestral area-they don't make any claim that that is 100% confident. It is a best guess & could change a little in time as more people are tested.
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Post by sherri on Apr 1, 2017 22:42:08 GMT
If you want to test the system for accuracy, have a close relative of yours who lives on the other side of the world, submit their DNA to Ancestry and see what analysis you get. After all, "No one has closer DNA ties to you than your own children/brothers/sisters......etc.".
You would definitely get a match, that's what I was trying to say.
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Post by sherri on Apr 1, 2017 22:53:30 GMT
You know what one of my dearest wishes is with this DNA testing? It is that one day, someone in what we think is my mother's father's line (and not too far back) will get DNA done and show a match. 2nd-3rd cousin range. Till that happens, we won't know if we are on the right track or not. My grandfather changed his name, covered his tracks, had no contact with any family whatsoever.
And I also know that an uncle fathered a child who was adopted out. My uncle was about 17 at the time. What happened to that child or what name they are under I have no idea, but I do know he lives in NZ. So if ever he has DNA done and I come up with an unknown cousin, bingo! I already know of someone who discovered a cousin they didn't know about!
Ancestry plays it down but it is also a bit of a paternity test. The fact I match cawoods & culyerra (both from my father's side) proves that.
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Post by sherri on Apr 2, 2017 2:51:33 GMT
Found this: Again, you will have to click to enlarge it. Basically, it just shows the average amount of DNA shared across different relationships. With a parent, you'll have half of your DNA as a match. And it goes down a bit from there.
So to answer if ancestry could match you with a sibling. Yes, because there is a lot of DNA to match to. Ancestry DNA isn't an expensive matching test so it can't do what some of the really expensive ones do & tell you whether parts of your DNA are from your mother or father, but it does a good job of matching you with close family. By 4th cousins or more, not so much. Hit or miss. My sister has some 5th-8th cousin matches that I don't have in my list, for example. Obviously I didn't share quite enough DNA with those people for ancestry to confidently predict any relationship.
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Post by DADDY O on Apr 2, 2017 11:54:25 GMT
I possibly haven't explained it all very well daddyo. But the DNA analysis done by Ancestry would pick up a close relative in a heartbeat and also tell you the most likely relationship.
But only if your relative had taken the Ancestry.com test also. That is the limit of their database. One HAS to have another person to have taken the test in order to " Compare" the results to. Ancestry.com DOES NOT have access to every DNA test ever done in the world. And, I won't even get into lab error, multiple labs performing DNA tests using separate standards....etc. The end result is..................you will never know if you were related to any of the original convicts in Australia through DNA testing..........because, they were never tested. That's the only point I was making.
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Post by sherri on Apr 2, 2017 23:08:43 GMT
It goes without saying that it can only show a DNA match with a living person (or someone who was alive when tested) and that if a person doesn't get tested, it can't show you that you match with them. Isn't that the same though with a lot of things? A medical scan might be easily able to show eg if someone has a tumour, but it can only show it if someone actually has the scan.
I can't be tested against my original convict ancestor. However, it would be easy to fall into the trap of thinking that convict was too far back. He wasn't.
Did you read the story about how Jack the ripper was been pretty well identified? The DNA (from semen) on a scarf of a victim was identified & DNA of living descendants of the main suspects taken and a match was found. It's not definite proof of course but it's pretty damning in my eyes. It makes that suspect a front runner in my opinion.
In a similar way, although I can't test my dead convict (unless we dug him up & did more extensive dna tests than available with ancestry) then what I can do is look at that convict's family tree-his children & their children etc If I have several dna matches with those living distant cousins (and some have been tested) then there's a good chance of a relationship. Also I am showing matches with a lot of people I don't know & where we can't see any names in common on our family trees, but both family trees go back to Peter port in the Channel Islands. Which is where our convict came from.
So we can't say 100% we have the convict's dna in us but we can say(I believe) that there is a high likelihood.
It's interesting you mention him as it has been a hotly debated topic with a certain group. I am in touch with a group of women on ancestry, all strangers, but who were interested in our convict and his 2 families (he was married twice). Now, we can't know this for sure, but we suspect our convict's first marriage broke up just after the birth of his 4th child because of a fight over the paternity. Our convict went over to NZ for a while to fight in the Maori wars & his wife suddenly sailed over to visit him. She gave birth a few months later. The baby was given his surname but I suspected she was about 6 weeks pregnant when she rushed over. After they broke up, she almost immediately moved in with another man & ended up having several other children.
Her 4th child though was born Frederick Anquetil but died under the name Frederick Anquetil Willmore.
Now it is easy for me, I am descended from a daughter of his from well into his second marriage.
But one of the women in the group is descended from Frederick Anquetil Willmore. For many years she assumed our convict Edward Anquetil was the father and Ebenezer Willmore the stepdad. But she recently had a DNA test done with ancestry. Put it this way: She & I have no match in DNA. Yet if Our convict had been her ancestor, you would think we likely would have as it is only 3 or 4 generations back.
So yes, you're right, the dna tests are not 100% proof of the past, we're dealing in probabilities, but I think it helps with more educated guesses if you like.
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Post by DADDY O on Apr 3, 2017 14:18:20 GMT
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