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I just noticed that I have a new FF match from New Zealand. The surname looks Irish. I now have 66 pages of FF matches, most from my colonial ancestry lines.
I just noticed that I have a new FF match from New Zealand. The surname looks Irish. I now have 66 pages of FF matches, most from my colonial ancestry lines.
I don't get how most people here get dozens upon dozens of pages and I get only three remote matches.
I get that I will get less matches, because first, I come from a country and a region(Maghreb) where very few people test themselves compared to the west, and second, I come from an endogamous rural group from that region.
However, I didn't expect the difference to be this drastic. I still expected a few pages worth of results, not three who are more than 5 generations removed.
I don't get how most people here get dozens upon dozens of pages and I get only three remote matches.
I get that I will get less matches, because first, I come from a country and a region(Maghreb) where very few people test themselves compared to the west, and second, I come from an endogamous rural group from that region.
However, I didn't expect the difference to be this drastic. I still expected a few pages worth of results, not three who are more than 5 generations removed.
Your results are not that surprising. American testing companies are very biased towards western Europe and Ashkenazis. As you note, coming from an endogenous group in an undertested region significantly restricts your matches. There have been threads from people with North African ancestry. There is also a limited amount of research on North African dna. See the article on the genetic history of North Africa at Wikipedia.
Your results are not that surprising. American testing companies are very biased towards western Europe and Ashkenazis. As you note, coming from an endogenous group in an undertested region significantly restricts your matches. There have been threads from people with North African ancestry. There is also a limited amount of research on North African dna. See the article on the genetic history of North Africa at Wikipedia.
The Wikipedia article is consistent with your low number of matches. It suggest that a significant number of autosomal SNPs are unique to the Magrheb.
There is a correlation between wealth in general (not just GDP of the country of residence) and genetic testing. Thus even Europe is very far from being uniformly represented.
However, I am not writing this post to state the semi-obvious, as the above
Your results are interesting because occasionally there are discussion here about levels to which descendants of Sephardim (trivializing: Jews from Spain) have an admixture from Maghreb. And the same question about Spaniards... I think you read some of these posts.
Can you guess, judging by names and whatever information is available in their profiles, origins of those three matches? Can you please share here the guesses?
W. (Mr.)
P.S.
This is a non-trivial question... When was your Family Finder test completed?
There is a correlation between wealth in general (not just GDP of the country of residence) and genetic testing. Thus even Europe is very far from being uniformly represented.
However, I am not writing this post to state the semi-obvious, as the above
Your results are interesting because occasionally there are discussion here about levels to which descendants of Sephardim (trivializing: Jews from Spain) have an admixture from Maghreb. And the same question about Spaniards... I think you read some of these posts.
Can you guess, judging by names and whatever information is available in their profiles, origins of those three matches? Can you please share here the guesses?
W. (Mr.)
P.S.
This is a non-trivial question... When was your Family Finder test completed?
There is a correlation not only with wealth but with cultural attitudes toward science and dna testing
In my previous post I used the word 'bias' strictly in the statistical sense (i.e. un-representative) which unrelated to any socio-political meaning.
Can you tell me why I have had only one same surname match in seven years. My Y DNA Haplogroup is 1-CTS10140. Can I also ask why there are a few non same surname Y DNA matches that are in some numbers, that is 12 or more matches. In terms of Genealogy
What has occurred to bring this about?
Can you tell me why I have had only one same surname match in seven years. My Y DNA Haplogroup is 1-CTS10140. Can I also ask why there are a few non same surname Y DNA matches that are in some numbers, that is 12 or more matches. In terms of Genealogy
What has occurred to bring this about?
Do you belong to a project? Can you tell us your kit number?
Can you tell me why I have had only one same surname match in seven years. My Y DNA Haplogroup is 1-CTS10140. Can I also ask why there are a few non same surname Y DNA matches that are in some numbers, that is 12 or more matches. In terms of Genealogy
What has occurred to bring this about?
You need to ask your question under the Y-DNA section (not autosomal) for more information about your subclade but that is OK, I will answer it in general.
If people who are your cousins with your surname never test, then you will not find a match. Sometimes you have to encourage your distant cousins or people with your surname to test with Y-DNA. But there is still no guarantee.
Y-DNA matches can last many centuries which is in contrast to autosomal DNA where you may only find close cousins. Y-DNA takes you back farther in time so the most recent common ancestor may be so far back that you have a hard time finding the connection, but often the surname is the same when you do find a match.
Y-DNA changes so slowly and does not mix like autosomal DNA so a male will always resemble his biological father and grandfather for the entire Y chromosome. You don't have to worry about segment matching.
Surnames change for whatever reason (adoptions, misappropriated paternity etc.) so there can be the same DNA results with a different surname. Males may take on the name of a slave-owner or a clan chief without being related too. The new surname can persist for many generations too. Often you will see two groups of people with two surnames and very similar Y-DNA results suggesting a name change in the distant past.
Alternatively the same surname can have Y-DNA that is entirely different.
Many people do find significant surname-haplotype persistence (correlation of the name with the results), especially when there is a progenitor who has many descendants. People who have immigrant ancestors in America often like to do genealogy and seem to network with other people of the same ancestry and then they form large groups with the same surname.
If there is a 97% chance the DNA and surname are linked in every generation, then there is a 74% chance the same surname-haplotype persistence will still be there after 10 generations. But there is still a 26% chance you will have lost the link of that DNA to that surname.
If names change a lot and people have children with unknown fathers, then the loss of a surname matching to that particular Y-DNA is much, much higher than this. If you assume that there is a higher non-paternity rate of 10% per generation, (i.e. there is only a 90% chance that the surname and DNA survives together after each generation), then there is only a 35% chance that the surname and DNA will persist together after 10 generations.
I'm Japanese and I have zero matches here, a real surprise, since I have 175 on 23andMe. FT confirmed that there was no error. A cousin who was not tested at FT has nearly 200 on 23andMe, and about a dozen on Ancestry. I'm guessing that FT has a very small percentage of orientals in its database.
I'm Japanese and I have zero matches here, a real surprise, since I have 175 on 23andMe. FT confirmed that there was no error. A cousin who was not tested at FT has nearly 200 on 23andMe, and about a dozen on Ancestry. I'm guessing that FT has a very small percentage of orientals in its database.
There could be are some demographic factors involved, but the total size of the database is one consideration. Ancestry and 23andMe each have one million customers. FTDNA does not release the size of the Family Finder database, but it's probably about 1/5th the size. That should still net you a few matches.
Another factor that affects matches at FTDNA is their algorithm, which requires 20 cM total including small 1-3 cM segments. Those small segments are likely to be false positives, but they are easier to find in people who come out of the same general gene pool.
One way to check this hypothesis out is to upload your kit to GEDmatch and see if you actually do match some Family Finder kits.
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