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firemonkey
07-01-2019, 10:24 AM
With a person with mostly Iberian ancestry 98.7% to be precise. 510 shared matches.

chr 9- 9.4 cMs in pile up region

chr 12 -9.3 cMs

chr 13- 6.1 cMs

chr 15 - 7.1 cMs

chr 22 -7.7 cMs

Only ethnicity we have in common is Finnish 2.2 % me and 1.3% her.

Shadogowah
07-09-2019, 06:25 AM
Every now and again I also find many Scandinavian matches with pretty decent amounts of total shared DNA (40-ish cM) but it is always spread among 3 or more segments making the longest one actually in the range of 8-9 cM. As I have my parents tested too I am positively sure these are false positives but of course I can't be sure of your case.

As far as I know, the most reliable parameter to identify a match is the length of the longest segment shared and not the total amount. If the segment is smaller than 12 cM, most likely it is a false positive.

msmarjoribanks
07-09-2019, 02:12 PM
Yes, I agree with the above. I have a lot of matches on MH, if I sort by location, that seem to have a decent overall match, but all the segments are under 10 and they don't match either of my parents. So false matches.

I expect these exist on FTDNA too, but I don't see them since I haven't had the ability to check out matches in other countries, so have just been working my way down from most significant match and don't get to the fluke ones.

firemonkey
07-09-2019, 02:36 PM
On FTDNA I've got quite a few 3-5th cousin matches with over a 100 shared matches. My heritage gives me several Scandinavian matches with largest segment 13cMs or more and 100 or near to 100 shared matches.

C J Wyatt III
07-09-2019, 06:46 PM
At least anecdotally since FTDNA changed its chip, I seem to be getting more matches. Unfortunately, with even 2nd cousin matches, I am finding no plausibility with almost all when I examine the ones providing trees or ancestral names.

Jack

firemonkey
07-09-2019, 08:06 PM
I've contacted a good number of 2nd-4th cousins at FTDNA and have drawn a big blank. There's a YDNA same surname match that's 37-2 but won't test further despite my offer to pay. I have a 4th-remote cousin match(27-10) with someone who has ancestors with my surname but I've not been able to find a connection.
My father has a 3rd-5th cousin match on FTDNA and My heritage with someone who has an ancestor with our surname. That person doesn't match me on FTDNA or My heritage.

Shadogowah
07-15-2019, 07:35 AM
Today I had a Chinese match without any known European ancestry. We share one segment with length 11cM.

Seriously, they should rethink the thresholds.

C J Wyatt III
07-15-2019, 01:23 PM
Today I had a Chinese match without any known European ancestry. We share one segment with length 11cM.

Seriously, they should rethink the thresholds.

Keyword is "known". After circumnavigation became common, a lot of sailors spread their DNA around the globe.

It is not just the thresholds which need rethinking, but the whole methodology.

Shadogowah
07-15-2019, 02:51 PM
Keyword is "known". After circumnavigation became common, a lot of sailors spread their DNA around the globe.

It is not just the thresholds which need rethinking, but the whole methodology.

The possibility that I have a common ancestor with Mr. Wong in the last 500 years is probably several orders of magnitude more remote than having one with the other Scandinavian false positives I mentioned above.

Shadogowah
08-30-2019, 12:26 PM
New false positive popped up. A German lady with a very strong Northern European profile and without a single minimal percentage of anything that could imply any "Spanishness" in it.

Three segments shared. The longest one with an impressive length 30,6‎ cM, she is actually the first match with the longest segment just after my parents... And she does not match any of my parents at all.

How can you fail by that far?

firemonkey
08-30-2019, 01:03 PM
Is it just me , or do a lot of people on My H just put were they where born or are currently living? I get quite a lot of obviously British surname matches in non British countries .

Baltimore1937
09-01-2019, 05:19 AM
I also get quite a few who are living around the world, but not native to where they currently are. Spain has quite a few apparently British matches (distant cousins).

evon
09-01-2019, 05:44 AM
Is it just me , or do a lot of people on My H just put were they where born or are currently living? I get quite a lot of obviously British surname matches in non British countries .

Its supposed to be based on residence, not birth location, I would say that around 20% or so of our matches are migrats that live in another country than their birth country.

firemonkey
09-01-2019, 10:13 AM
Its supposed to be based on residence, not birth location, I would say that around 20% or so of our matches are migrats that live in another country than their birth country.


Perhaps they should have a 4 grandparents from the same country tool.

evon
09-01-2019, 06:41 PM
Perhaps they should have a 4 grandparents from the same country tool.

That would be more useful, but most would not bother with entering such information into myheritage, as most users are lazy and only want short term information.

Titane
10-22-2019, 08:40 PM
Perhaps they should have a 4 grandparents from the same country tool.

They do show the ancestry of the matches, just below the countries. Of course since many people are mixed, you get, well, mixed results...
I was curious to see who my Chinese matches were - and as expected, they are 50% Chinese/50%West European.

Of course, MH has also found me a good 25% proportion of Italian, which have no bearing in reality, not anymore than the 50% British. But then that is how Ancestry started too, after deciding I was 100% French. I suspect they decided to look at the trees...

tipirneni
10-25-2019, 01:32 AM
I am 100% South Asian Ethnicity, I get 32% European matches many of them 3rd (>11cM). Also on GED I get big number of European matches