This is not know by enough people : the Barbary slave trade etc

[ancientlight]

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I'm one-quarter Czech on my dad's side not to mention the Irish from Mom's side. How many generations can pass before I can't claim their enslaved history?

Interesting question. The DNA of entire ancestors starts dropping  out of your DNA after between 7 and 10 generations on one hand. SO, at that time, some individuals will no longer be represented in your DNA - but you don't get to choose which ones disappear from it.

On the other hand, all of your DNA had to come from someone, so some of them will always be represented in it, and you don't get to choose which of those are represented, either.

In either case, they are still your ancestors, whether their DNA shows up in yours or not.

As an example, I mentioned above that the Nigerian (that's right - I might be that Nigerian Price everyone e-mails you about!) DNA dropped out of mine between myself and my son. 1/10th of 1% of my DNA is Nigerian, but 0.0% of my son's DNA is Nigerian. The Nigerian ancestry is still there, and always will be, but it no longer shows up in his DNA.

However, some of my DNA traces back to a knot of un-named people between 2400 BC and 1700 BC who lived in the Prague, CZ area, and it is still present in both mine and his DNA. That DNA will always be around, because all of our DNA has to come from somewhere, and it is the luck of the draw that it remains present.

I still carry Pictish DNA from Scotland, 1500 years after the Picts ceased to be a separate ethnic group. My DNA still scores a match with Cheddar Man, from 9000 years ago - the Neolithic of Britain. It's just the luck of the draw that his DNA persists while the DNA  of other ancestors from the same time period around the world has long since vanished from mine.

Going even farther back, I carry more Neanderthal DNA than 83% of the rest of humanity, and the Neanderthals vanished as a species 24,000 to 28,000 years ago. I carry DNA from Bangladesh that is so old that there is no record of whom it came from, or how it got into the family tree.

My paternal Y-DNA traces back all the way to the Balkans or Northern Greece during the late Neolithic or early Bronze age, and was probably carried into Central Europe during an invasion from the Balkans, and only persisted because the invaders carried better weaponry, made of bronze, than the native population had, who still had a chipped flint technology.

I have a Powhatan Indian woman in my ancestry from around 1620 or so that some tests can detect, but others do not. Her name is listed simply as "Powhatan Mary" in the genealogical paper trail. The reason some tests pick her DNA up and others do not is down to the database they are comparing the DNA against - some of them contain Indian DNA for comparison, and some do not... so the Indian DNA is ascribed to the next closest thing that IS represented (usually a Siberian or Central Asian), because that particular database doesn't contain anything to match it to.

So, really, I reckon you can claim whichever ancestors you still have some evidence for, whether DNA or a paper trail, and you don't have to claim those that you don't have any evidence left pointing to them.

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That's so interesting all, I love it! I'd love to do DNA ancestory testing, but they keep/sell your DNA data.  
How did you do it , which site?