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sktibo
06-12-2017, 05:39 AM
I only have a mere 0.2% Ashkenazi on my 23andme ethnicity estimate, which I previously regarded as just noise in the past as it hasn't shown up on any other test. A few things are making me question whether or not it is real... the first being that I've spent over a year now on this forum looking at various ethnicity estimates from various companies and various individuals and noticing that 23andme seems to be the best autosomal calculator. The second thing is that over this year or so I've also been working on my paper trail, gathering up every record I can find in my family, and talking to the family members I have which are still alive. My maternal line comes from Eastern Europe during a time when borders were constantly changing. Today, this place is within the boundaries of the Ukraine, but I believe it was Romania when these ancestors left and came to Canada. The paper trail on this line hits a wall with a person whose surname appears to be "Tabak" which apparently can be a Jewish surname. The combination of this location and this surname make me wonder if this tiny percentage might be real?

So, I'd like to pose the question to anyone else out there who has received an Ashkenazi Jewish percentage on 23andme: Do you think it was accurate?

Thank you

NewAlbion
06-12-2017, 06:04 AM
Hello, skitbo, I haven't tested with 23andme. You say they are the most accurate but I find the British+Irish category too vague and politically controversial so that is why I won't test with them. As far the AJ thing I noticed something strange on another anthropology forum. Everyone who posted their ancestry timeline showed a Jewish ancestor, no matter what race or ethnicity, which made me skeptical because 23andme is owned by AJ Jews. Hopefully, you can get more helpful responses from people who tested with 23andme as my observation may be wrong or the thread in question may be a stastical anomaly.


P.S. at 0.2 percent I would say it does not matter unless you suck at math.

raschau
06-12-2017, 06:28 AM
Everyone who posted their ancestry timeline showed a Jewish ancestor, no matter what race or ethnicity, which made me skeptical because 23andme is owned by AJ Jews.

I'm just going to highlight this as an absolutely absurd thing to say.

Luis
06-12-2017, 06:36 AM
Skitbo, everyone says 23andMe is the best when it comes to detecting real AJ ancestry. The key is to have AJ matches, do you have any there? Many companies now show some AJ% even for people who did not show any, or very little, when they tested with 23andMe. 23andMe have their own AJ samples, which is made up of many, and they compare you to those in their sample. Other companies detect affinity, perhaps based on some shared ancestry with AJ, but it does not necessarily mean those showing a % have real AJ ancestry. FTDNA has this category, as well as Sephardic Jewish now. Many who score SJ ancestry do not really have it, but do share a lot of similarity to their sample. According to the opinion of many people, 23andMe is the most accurate detector of AJ ancestry.

sktibo
06-12-2017, 07:39 AM
Skitbo, everyone says 23andMe is the best when it comes to detecting real AJ ancestry. The key is to have AJ matches, do you have any there? Many companies now show some AJ% even for people who did not show any, or very little, when they tested with 23andMe. 23andMe have their own AJ samples, which is made up of many, and they compare you to those in their sample. Other companies detect affinity, perhaps based on some shared ancestry with AJ, but it does not necessarily mean those showing a % have real AJ ancestry. FTDNA has this category, as well as Sephardic Jewish now. Many who score SJ ancestry do not really have it, but do share a lot of similarity to their sample. According to the opinion of many people, 23andMe is the most accurate detector of AJ ancestry.

I've identified one match so far with some overlapping surnames who is half Ashkenazi, and my tiny AJ segment matches one of his also identified as AJ. I sent a message to this individual and hopefully I'll hear back.
thanks very much for your input, I'll start trying to see if i can find some more matches.

GogMagog
06-12-2017, 07:54 AM
I am 0.1% and can find no paper trail link. Yes, Tabak is an Askenazim name.

Cinnamon orange
06-12-2017, 08:00 AM
Do you show Jewish matches at that location on 23andme or gedmatch? With a small percentage you may be hitting the cutoff for matches. Triangulation helps.

sktibo
06-12-2017, 08:08 AM
Do you show Jewish matches at that location on 23andme or gedmatch? With a small percentage you may be hitting the cutoff for matches. Triangulation helps.

23andme. hopefully I'll be able to locate some more matches and get their gedmatch numbers. Cheers!

sktibo
06-12-2017, 08:09 AM
I am 0.1% and can find no paper trail link. Yes, Tabak is an Askenazim name.

Thank you, so do you think it is noise then in your case?

MindHive
06-12-2017, 04:04 PM
I agree. It is sometimes noise, not to mention people also getting Yakut at 0.1. Crazy thing to say that because the CEO happens to be Ashkenazi they just insert small amounts to skew results, I feel like Albion might be one of the people who think Jews control the world. Absurdity at its best. Okay im done. I feel like this could go off the rails if this is further discussed so I won't say anything else.

MindHive
06-12-2017, 04:06 PM
It sounds like it is more than noise for you skitbo. Does it still show up if you lower confidence? If it disappears at a certain confidence level, what level is that?

Roaring
06-12-2017, 05:08 PM
23andme is best so far for detecting AJ, in your case it's still hard to tell, since the percentage is too small to be shure, as others said best way is to look for matches.

P.S. what is the name of the place your ancestirs came from? I may google for jewish settlements in this area.

Luis
06-12-2017, 05:36 PM
I've identified one match so far with some overlapping surnames who is half Ashkenazi, and my tiny AJ segment matches one of his also identified as AJ. I sent a message to this individual and hopefully I'll hear back.
thanks very much for your input, I'll start trying to see if i can find some more matches.

23andMe usually identified AJ matches as "Distant Cousins", instead of giving a range like 3rd-5th cousin. Even if the segment inherited would normally classify that match as a "4th cousin". If the match was only half AJ, then this match would be classified as either a 4th or 5th cousin. For example, my brother and his children have a lot of these full AJ Distant Cousin matches, plus some who are only partially so. I did not get any. We do not have AJ ancestry, but my brother and his son show 0.2, my niece 04%, while I only have about 0.1%. The matches I'm sure are real and they point to a common ancestor. On the other hand, FTDNA gives me 3.0% AJ, My Heritage 1.8% and WeGene 0.55%. Ancestry DNA gives me less than 1%.

sktibo
06-13-2017, 12:33 AM
23andme is best so far for detecting AJ, in your case it's still hard to tell, since the percentage is too small to be shure, as others said best way is to look for matches.

P.S. what is the name of the place your ancestirs came from? I may google for jewish settlements in this area.

Zastavna, Chernivtsi, Ukraine is the modern location of where my Tabak ancestor's granddaughter was born. that's the closest location I have unfortunately.

sktibo
06-13-2017, 12:34 AM
It sounds like it is more than noise for you skitbo. Does it still show up if you lower confidence? If it disappears at a certain confidence level, what level is that?

Soon as i get to a computer i can check this. Right now i can't figure out how change confidence levels on my phone

Roaring
06-13-2017, 01:59 AM
Zastavna, Chernivtsi, Ukraine is the modern location of where my Tabak ancestor's granddaughter was born. that's the closest location I have unfortunately.

Information from Russian wikipedia, i did google translate, but it doesn't look that bad, if you'll have problems understanding the text feel free to ask me for a manual translation.

The first Jews, immigrants from Galicia, settled in Zastavna in the early 18th century. In 1810, all Jews engaged in trade were evicted from the city. Only two families, engaged in agriculture, were allowed to stay. After the liberalization of the "Jewish policy" of Austrian powers in the 2nd half. 19th century. Jews again began to settle in Zastavna. In 1870, a cemetery was founded on which the Jews of all the surrounding villages were buried. There were 3 synagogues, mikvah, Talmud-torah. There was a rabbi and a shokhet. In 1891, Zastavny were brought into the community, the council consisting of 13 people included Jews from 29 small settlements in the Nistru region. The economy of the Jews was based on the growing of grain. The Jews realized 2 mills and 6 peasant estates. Jews also engaged in grain trade and petty trade. Despite the fact that economic influence was quite high: for some time the mayor was shut up. He was Jewish, Jews were repeatedly elected to the post of deputy. Mayor, at the same time they occupied many public positions: judges, postal workers, officials of the mayoralty, tax service and gendarmerie.

In 1904, Zionist organization "Theodore Herzl", which existed until 1940, began to operate in the Zastin. The first chairman of the Zionist organization of Bukovina was Zagmond Veisglas, the prisoner. In 1909, the municipality opened a Jewish school, in which non-Jews also studied. During the First World War, almost all Jews were forced to flee to Austria and returned after it was over. After the war, only one Jew remained in the civil service. After 1918, a school was opened in Zastavna with teaching in Hebrew. In 1922 a branch of the WICO - International Women's Zionist Organization was established. In the 1920-30's. In the Screensaver, there were active branches of various Jewish parties.

In June 1941, German and Rumanian troops entered the Screensaver. The Jews of the town and the surrounding villages were imprisoned in the ghetto. In October 1941, all Jews were sent to cross-border and territorial cities (Obodovka, Bershad, Tulchin, Yampol). Most of them died, about 10% of Jews are left alive. After 1945, about 40 Jews returned to Zastavna; But after a while almost all went to Romania, and from there - to Israel. Three synagogues were given under the barns for grain, and a large cinema opened in the building of the Great Synagogue. In the 1960s. In Zastavna lived several Jews who moved from the eastern regions of Ukraine. Today (2016) there are no Jews here. The Jewish cemetery was demolished, its territory was given as a restaurant. Behind the building of the restaurant was a small area where the remaining matzevs were buried, a monument was erected on top.

In 1774 there were 17 Jews living in the Zastavna,
** In 1776 - 33,
** In 1808 - 100 Jewish families,
** In 1910, there were 418 Jews,
** In 1930. - 629 Jews (12.3%).



So all in all it does seem that this Tabak being Ashkenazi is a fairly truthfull story.

sktibo
06-13-2017, 02:11 AM
Information from Russian wikipedia, i did google translate, but it doesn't look that bad, if you'll have problems understanding the text feel free to ask me for a manual translation.

The first Jews, immigrants from Galicia, settled in Zastavna in the early 18th century. In 1810, all Jews engaged in trade were evicted from the city. Only two families, engaged in agriculture, were allowed to stay. After the liberalization of the "Jewish policy" of Austrian powers in the 2nd half. 19th century. Jews again began to settle in Zastavna. In 1870, a cemetery was founded on which the Jews of all the surrounding villages were buried. There were 3 synagogues, mikvah, Talmud-torah. There was a rabbi and a shokhet. In 1891, Zastavny were brought into the community, the council consisting of 13 people included Jews from 29 small settlements in the Nistru region. The economy of the Jews was based on the growing of grain. The Jews realized 2 mills and 6 peasant estates. Jews also engaged in grain trade and petty trade. Despite the fact that economic influence was quite high: for some time the mayor was shut up. He was Jewish, Jews were repeatedly elected to the post of deputy. Mayor, at the same time they occupied many public positions: judges, postal workers, officials of the mayoralty, tax service and gendarmerie.

In 1904, Zionist organization "Theodore Herzl", which existed until 1940, began to operate in the Zastin. The first chairman of the Zionist organization of Bukovina was Zagmond Veisglas, the prisoner. In 1909, the municipality opened a Jewish school, in which non-Jews also studied. During the First World War, almost all Jews were forced to flee to Austria and returned after it was over. After the war, only one Jew remained in the civil service. After 1918, a school was opened in Zastavna with teaching in Hebrew. In 1922 a branch of the WICO - International Women's Zionist Organization was established. In the 1920-30's. In the Screensaver, there were active branches of various Jewish parties.

In June 1941, German and Rumanian troops entered the Screensaver. The Jews of the town and the surrounding villages were imprisoned in the ghetto. In October 1941, all Jews were sent to cross-border and territorial cities (Obodovka, Bershad, Tulchin, Yampol). Most of them died, about 10% of Jews are left alive. After 1945, about 40 Jews returned to Zastavna; But after a while almost all went to Romania, and from there - to Israel. Three synagogues were given under the barns for grain, and a large cinema opened in the building of the Great Synagogue. In the 1960s. In Zastavna lived several Jews who moved from the eastern regions of Ukraine. Today (2016) there are no Jews here. The Jewish cemetery was demolished, its territory was given as a restaurant. Behind the building of the restaurant was a small area where the remaining matzevs were buried, a monument was erected on top.

In 1774 there were 17 Jews living in the Zastavna,
** In 1776 - 33,
** In 1808 - 100 Jewish families,
** In 1910, there were 418 Jews,
** In 1930. - 629 Jews (12.3%).



So all in all it does seem that this Tabak being Ashkenazi is a fairly truthfull story.

I should mention that this side of my family married people with German looking surnames from Galicia Poland. IIRC Zastavna bordered Galicia Poland and my ancestors from Galicia were from a town which was fairly close to Zast. Happy to provide you with more info via PM if you think it might be useful? You don't have to look any more into this of course!
Thank you for digger this up for me!

Roaring
06-13-2017, 02:20 AM
I should mention that this side of my family married people with German looking surnames from Galicia Poland. IIRC Zastavna bordered Galicia Poland and my ancestors from Galicia were from a town which was fairly close to Zast. Happy to provide you with more info via PM if you think it might be useful? You don't have to look any more into this of course!
Thank you for digger this up for me!

I'm currently lying ill in bed due to the fact that i managed to catch cold in June (Russia, what would you think) as far as it's been that way for about a week i'm happy to do any sort of work as my usual hobbies already bored me to death, so feel free to send me PMs.

sktibo
06-13-2017, 03:48 AM
Soon as i get to a computer i can check this. Right now i can't figure out how change confidence levels on my phone

On "Speculative" 50% I am at 0.2% AJ.
On 60% I am at 0.2% AJ.
On 70% I am at <0.1% AJ.
On 80 and 90% "Conservative" The tiny AJ percentage is gone. I'm honestly quite surprised that it remains at 70% confidence.

MindHive
06-13-2017, 03:36 PM
If it is still there at 70 percent, I would say that more than likely, you have an Ashkenazi ancestor somewhere along the way.

Dorkymon
06-13-2017, 06:57 PM
I only have a mere 0.2% Ashkenazi on my 23andme ethnicity estimate, which I previously regarded as just noise in the past as it hasn't shown up on any other test. A few things are making me question whether or not it is real... the first being that I've spent over a year now on this forum looking at various ethnicity estimates from various companies and various individuals and noticing that 23andme seems to be the best autosomal calculator. The second thing is that over this year or so I've also been working on my paper trail, gathering up every record I can find in my family, and talking to the family members I have which are still alive. My maternal line comes from Eastern Europe during a time when borders were constantly changing. Today, this place is within the boundaries of the Ukraine, but I believe it was Romania when these ancestors left and came to Canada. The paper trail on this line hits a wall with a person whose surname appears to be "Tabak" which apparently can be a Jewish surname. The combination of this location and this surname make me wonder if this tiny percentage might be real?

So, I'd like to pose the question to anyone else out there who has received an Ashkenazi Jewish percentage on 23andme: Do you think it was accurate?

Thank you

Read about precision, recall and consult the table.
https://www.23andme.com/en-gb/ancestry-composition-guide/

I also have only 0.3%, but I'm loaded with Jewish matches.
A quick way to filter, though you'd obviously exclude most of your matches, is by surname in Relative Finder.
Check those that seem Jewish, compare the results, segments and then scroll down to the bottom of the page and look at the relatives that you both have in common. So on and so forth until you get bored.

http://i.imgur.com/l6uBh7t.png

bryan
06-13-2017, 08:17 PM
I'd take into consideration of having the possibility to have some Ashkenazi heritage if you score above 1% on 23andme and you have at least a couple of *full AJ on your relative list. 0.2% seems like almost noise, I've seen people of Norwegian ancestry who got 0.2% West African and they had no any heritage from there.

Ric
07-13-2017, 10:49 PM
I think less than 1% is real, but just too far back. Most french from western France get BritishIrish above 40% yet they can't find any BI ancestor, same for me. So when you think about finding a 0.3% ancestor, just forget it. He could be a thousand years old.

Ric
07-14-2017, 01:19 AM
http://i.imgur.com/l6uBh7t.png
Regarding this list, some names seem to be recurrent for everybody that get a significant B/I ancestor at 23&me.
There is another French on this forum and myself, with no known B/I genealogical record, but with significant B/I % (more than 10%) and we have quite a lot of DNA relatives from the British isles. Our lists of DNA relatives are enriched in the same names here : Anderson, Moore, Miller, Smith, Martin, Johnson, Jackson.
It makes me think that British/Irish DNA is made of Anderson's or Johnson 's DNA, literally. 'As if' families with these surnames were particularly successful and spread sufficiently so that we can now either talk of 'British/Irish' DNA, or of Anderson' s DNA, either ways. Inversely, if you have some significant B/I % ancestry, you gonna have some DNA relatives with these names, even if actually there is nothing specific about it.

That could explain the puzzle with the double matches Y-STR and Autosomal : basically many men from Western Europe, including the British Isles, are R1b which means that these r1b men all share STR patterns at least at some low level, and for those British R1b men, made of 'Anderson, Miller, etc.' DNA, it becomes quite likely that a R1b Frenchman with some B/I component like me, who match Andersons with STR, is also going to match Andersons with autosomal. Also, considering that people who had an STR test are also more likely to have an autosomal test than people taken randomly, the occurrence of double match STR/Autosomal is almost inevitable. Yet there is nothing really specific with a low level STR matches that is also a 'distant' autosomal matches. Distant means 5th cousin.

Perhaps Askenazi DNA is similar and DNA relatives named Cohen are not really specific, and similarly, Cohen's double matches (low level STR + autosomal 5th cousin) may occur quite easily, and fool you that it is real.

Ric
07-14-2017, 01:30 AM
I'd take into consideration of having the possibility to have some Ashkenazi heritage if you score above 1% on 23andme and you have at least a couple of *full AJ on your relative list. 0.2% seems like almost noise, I've seen people of Norwegian ancestry who got 0.2% West African and they had no any heritage from there.IMO, it is probably real. Look at Americans of European descent, many have a small African % but they can't document it after only 200 years.
OK, they probably hurried to forget, but that is another topic. It is just very hard to document all your lines down to 250/300 years. The direct paternal and maternal lines are exceptions only thanks to Y-STR and Mitochondria, but in between, even the Queen of England cannot be sure of all her ancestors 300 years ago.

Erik
07-14-2017, 02:01 AM
which made me skeptical because 23andme is owned by AJ Jews

Replace "23andme" with "the media" and we've got a classic antisemitic conspiracy theory here. Is Jews running the DNA companies going to be the next new elders of Zion?

.

Anyway, to get back to the actual topic of the thread... if your family is from Eastern Europe and you have an Ashkenazi surname in your family tree then there you have it!

sktibo
07-14-2017, 02:23 AM
I got my dad's results from Ancestry in and to my surprise he had a tiny bit of Ashkenazi show up... He has some ancestors from England with Hebrew first names who didn't appear to list their religious denominations, but I looked into it as well as I could and decided they probably weren't the source of my tiny AJ percentage. Now I'm wondering if they might be, I'll have to get my mother tested to be certain of course.

JMcB
07-14-2017, 03:55 AM
Quote Originally Posted by NewAlbion
Everyone who posted their ancestry timeline showed a Jewish ancestor, no matter what race or ethnicity, which made me skeptical because 23andme is owned by AJ Jews.



I'm just going to highlight this as an absolutely absurd thing to say.

Personally, I think absolutely absurd is a very charitable way to characterize it. Nevertheless, I hope that you are right and that's all it was.

Ric
07-14-2017, 11:54 AM
here is my list, I have 17%B/I, no known genealogical record of any British ancestor for at least 4 generations on all my branches (I have 64 names listed) 17532
the list from the other French guy is similar, and we are not related.
So....

By the way, (that has nothing to do with the thread) but if you guys still post in the 23&me forum, perhaps you could encourage people to post some family names. An 'anonymous' with initials and a few surnames listed is more useful than a public profile with zero surnames listed. The trend for zero surnames listed seems to grow at 23&me, and unfortunately at ftdna FF too.

Simon_W
07-14-2017, 12:41 PM
I got a 0.1% Ashkenazi segment on my chromosome 1. Since it's on the maternal half and in a genomic region where I match my maternal grandmother, it must be from her. She's from Southwestern Germany and Northwestern Switzerland, in an area where many Ashkenazi Jews lived before they were expelled to eastern Europe. I didn't test my grandmother on 23andme, but for instance on FTDNA she got 5% Levantine ancestry (which is of course less reliable than 23andme). There is no reason to regard small exotic segments as noise, after all even these are segments that are considered by 23andme to have a sufficient likelihood of being from the population in question. And bear in mind that you can check and adjust the necessary threshold of which likelihood is considered "sufficient" yourself. In my case the Ashkenazi segment is only there if the confidence threshold is set to 50%, and it disappears when I set it to 60%. So it's somewhat speculative. But what makes me quite sure about its reality is the fact that I found 3 seemingly purely Ashkenazi matches from eastern Europe who match me in precisely this segment. The most recent common ancestors must have lived many centuries ago, before the ancestors of these matches moved to eastern Europe.

Simon_W
07-14-2017, 12:55 PM
Quote Originally Posted by NewAlbion
Everyone who posted their ancestry timeline showed a Jewish ancestor, no matter what race or ethnicity, which made me skeptical because 23andme is owned by AJ Jews.


My dad's ancestry timeline:

17533

Simon_W
07-14-2017, 01:15 PM
Regarding this list, some names seem to be recurrent for everybody that get a significant B/I ancestor at 23&me.
There is another French on this forum and myself, with no known B/I genealogical record, but with significant B/I % (more than 10%) and we have quite a lot of DNA relatives from the British isles. Our lists of DNA relatives are enriched in the same names here : Anderson, Moore, Miller, Smith, Martin, Johnson, Jackson.
It makes me think that British/Irish DNA is made of Anderson's or Johnson 's DNA, literally. 'As if' families with these surnames were particularly successful and spread sufficiently so that we can now either talk of 'British/Irish' DNA, or of Anderson' s DNA, either ways.

These surnames are indeed very common in Britain. The least common of them, Miller, still has 109474 carriers, and Smith is the most common of all, with 729862. It's clear that they're not monophyletic, as they are derived from occupations that once were very common.

http://surname.sofeminine.co.uk/w/surnames/most-common-surnames-in-great-britain.html

Simon_W
07-14-2017, 01:29 PM
I don't consider 23andme's list of the top locations of one's DNA relatives to be very useful. This is mine:

17535

My gg-grandparents were all from Germany, Switzerland and Italy. Yet the list shows me the same number of DNA relatives in the UK as in Germany and Switzerland and not a single Italian DNA relative. I do have fully or partly Italian DNA relatives on 23andme, BTW and one of them still lives in Italy. Apparently he didn't indicate his location to 23andme or something like that, in any case he doesn't appear in that list.

Simon_W
07-14-2017, 01:41 PM
That could explain the puzzle with the double matches Y-STR and Autosomal : basically many men from Western Europe, including the British Isles, are R1b which means that these r1b men all share STR patterns at least at some low level, and for those British R1b men, made of 'Anderson, Miller, etc.' DNA, it becomes quite likely that a R1b Frenchman with some B/I component like me, who match Andersons with STR, is also going to match Andersons with autosomal. Also, considering that people who had an STR test are also more likely to have an autosomal test than people taken randomly, the occurrence of double match STR/Autosomal is almost inevitable. Yet there is nothing really specific with a low level STR matches that is also a 'distant' autosomal matches. Distant means 5th cousin.


True. The significance of STR matches, especially in the R1b branch, depends a lot on the number of markers considered. R1b in Western Europe is so common and exploded just a few thousand years ago that you need a lot of markers and a very good match to be sure about a relative in the genealogical time frame. On the other hand, even poor matches are relatives, just very distant ones with TMRCAs of thousands of years ago.

evon
07-14-2017, 01:56 PM
I only have a mere 0.2% Ashkenazi on my 23andme ethnicity estimate, which I previously regarded as just noise in the past as it hasn't shown up on any other test. A few things are making me question whether or not it is real... the first being that I've spent over a year now on this forum looking at various ethnicity estimates from various companies and various individuals and noticing that 23andme seems to be the best autosomal calculator. The second thing is that over this year or so I've also been working on my paper trail, gathering up every record I can find in my family, and talking to the family members I have which are still alive. My maternal line comes from Eastern Europe during a time when borders were constantly changing. Today, this place is within the boundaries of the Ukraine, but I believe it was Romania when these ancestors left and came to Canada. The paper trail on this line hits a wall with a person whose surname appears to be "Tabak" which apparently can be a Jewish surname. The combination of this location and this surname make me wonder if this tiny percentage might be real?

So, I'd like to pose the question to anyone else out there who has received an Ashkenazi Jewish percentage on 23andme: Do you think it was accurate?

Thank you

With minor Jewish ancestry I would rely more on segment matches than on admixture, as when you go below a certain % there are several problems which hinder you. One major problem with 23andme is their smoothing algorithm, which basically means that larger segments overrule smaller ones, so if you have two large segments with "British" and a small "Jewish" segment in between, chances are that the small "Jewish" segment will be labeled as "British" too.

When dealing with segments alone and not admixture you have to try to triangulate them, luckily 23andme now offers the "matches in common feature", which is very helpful. It is also important to remember that certain ethnic groups such as "Jews" belong to a very small genepool, so you have to establish the direction of geneflow, that is to say; is this a "Jewish" segment you share with Jewish people, or a "British" segment that some Jewish people share with you.

Since I transitioned a few weeks ago I have been working on two 12cM segments on my 10th chromosome that I share with Jewish people, as well as people with only minor Jewish ancestry (I get no "Jewish" % in AC). While it is still a work in progress, it now seems likely that it is indeed Jewish in nature, but I think it is more likely Sephardic or something else, than Ashkenazi.

sktibo
07-15-2017, 05:29 AM
It's something of a side note but I want to know how you folks find FTDNA for their Jewish categories.. especially in comparison to Ancestry and 23andme in terms of accuracy. Thanks!

Simon_W
07-16-2017, 06:02 PM
With minor Jewish ancestry I would rely more on segment matches than on admixture, as when you go below a certain % there are several problems which hinder you. One major problem with 23andme is their smoothing algorithm, which basically means that larger segments overrule smaller ones, so if you have two large segments with "British" and a small "Jewish" segment in between, chances are that the small "Jewish" segment will be labeled as "British" too.

When dealing with segments alone and not admixture you have to try to triangulate them, luckily 23andme now offers the "matches in common feature", which is very helpful.

Not trying to disagree, but it has to be added that 23andme's Ancestry Composition isn't a tool based on the ADMIXTURE algorithm like so many other contenders are.

And apart from triangulation another way to establish certainty of a match between 2 people is phasing (can be done on GedMatch). If both DNA kits are phased and still have a sufficiently long match (about 6 cM), then it's definitely real.

Simon_W
07-16-2017, 06:08 PM
It's something of a side note but I want to know how you folks find FTDNA for their Jewish categories.. especially in comparison to Ancestry and 23andme in terms of accuracy. Thanks!

I cannot say much about Ancestry, but 23andme just has an Ashkenazi Jewish category, while FTDNA also has a Sephardic component. Would be interesting to know how reliable it is.

sktibo
09-23-2017, 09:40 PM
I suspect the mystery is over in my case, I now have my mother's Ancestry DNA results. To my surprise, she wasn't assigned any European Jewish, (but a whole lot of Eastern European - I guess her family wasn't quite as German as the paper trail indicates) while my father was assigned <1 Jewish and <1 Middle Eastern, indicating that it is my father from whom my tiny Ashkenazi 23andme percentage comes from. I'm truly surprised, but I suppose some of his English ancestors were part Jewish.

tomz
09-23-2017, 10:22 PM
I also show a tiny bit at .01. I know of no Ashkenazi Jewish ancestors in the last 6 generations at least. It is probably noise for me

Bobby Martnen
09-25-2017, 12:12 AM
Test your parents and living grandparents. If one parent has 0.4% Ashkenazi and one of their parents has 0.8%, it's a lot less likely to be statistical noise

Rafe
09-26-2017, 09:40 PM
I'm only 0.4% Ashkenazi on 23andme's test. Though the number is small, I've never suspected it of being inaccurate because on my Relative List there's a fair number of Jews - about 200 people, mostly Americans, and almost all of them match me on precisely the same segment in chromosome 12.

You should try to check how many Jewish relatives you have and if there's a strong concordance on the parts of your DNA where each overlaps with you. If your case is similar to mine, then I think you should consider the result legit.

However, I believe some Ashkenazi Jewish DNA may actually be Eastern European or vice-versa. I have a distant Mexican-American cousin on 23andme whose Ashkenazi and Eastern European results changed a lot during the last update, with one taking space from the other - I forget which one increased and which one decreased, though. Plus, I have a spreadsheet of the results of my Latin American matches, and noticed there's a positive correlation (r = .15) between Ashkenazi and Eastern European ancestry, so it's possible that the last update has not totally solved the mistaken use of ancestry labels between Ashkenazi and Eastern European DNA. FWIW, my Ashkenazi results have remained the same for years, since 23andme started breaking European ancestry down into subcategories.

JerryS.
09-26-2017, 09:46 PM
Ancestry .com does not list Jewish anything for me, but the Jtest shows me at 4.44% which according to the creator's math is 17.76%. go figure. the Jtest says 3% and less is little to no Jewish, and that 25% is full Jew (25 x 4 = 100?)

coffeeprince
09-26-2017, 09:57 PM
The Jtest is only relevant for Ashkenazi ancestry, and won't be accurate for Sephardi or Mizrahi ancestry.

Piquerobi
09-27-2017, 12:13 AM
I think it is very accurate.

coffeeprince
09-27-2017, 08:44 PM
I think it is very accurate.

Are you Sephardi or Mizrahi? Please post your Jtest results.

JerryS.
09-28-2017, 12:53 AM
Are you Sephardi or Mizrahi? Please post your Jtest results.

what? you said that test is only relevant for Ashkenazi.

JerryS.
09-28-2017, 12:54 AM
The Jtest is only relevant for Ashkenazi ancestry, and won't be accurate for Sephardi or Mizrahi ancestry.

........

coffeeprince
09-28-2017, 03:01 AM
Yeah, I thought the above post mentioned it was accurate for Sephardi/Mizrahi but he/she might just be replying to the thread title in general.

Piquerobi
09-28-2017, 11:09 PM
Are you Sephardi or Mizrahi? Please post your Jtest results.

I am not Jewish but I have seen several results over the years and they seem to confirm to me 23andme is very accurate when it comes to Ashkenazi Jewish ancestry.

Rafe
10-01-2017, 08:02 AM
I don't consider 23andme's list of the top locations of one's DNA relatives to be very useful. This is mine:

17535


Weird. Is there like a cap set at 880 on how many relatives one's allowed to have in a single country? This is mine: 19087

ianz91
10-03-2017, 03:21 PM
Ancestry .com does not list Jewish anything for me, but the Jtest shows me at 4.44% which according to the creator's math is 17.76%. go figure. the Jtest says 3% and less is little to no Jewish, and that 25% is full Jew (25 x 4 = 100?)


Wait what? You're saying that if someone scores 4.44% Jewish on jtest, they're actually not 4.44% Jewish, but 17%? Can you explain further? I'm confused.

Pylsteen
10-03-2017, 03:44 PM
Wait what? You're saying that if someone scores 4.44% Jewish on jtest, they're actually not 4.44% Jewish, but 17%? Can you explain further? I'm confused.

No this is not the case, since Europeans without Jewish ancestry also have about 3% (Northern Europe) till 8% (Italy) of what is called the Ashkenazi component on the JTest. A full Ashkenazi has ca. 20% Ashkenazi on the JTest, and also much East Med, West Asian etc. The Ashkenazi component on its own doesn't tell you anything if it isn't much more than the average of your main group of descent (see the spreadsheet on gedmatch for population averages).

For example, in my case, I know I have 1/16 Jewish ancestry; the average for Dutch is about 3% Ashkenazi on this test, I get 4,5%. I also have more East Med than average; together these "excesses" would be attributable to my Jewish gg-grandmother.

ianz91
10-03-2017, 03:49 PM
No this is not the case, since Europeans without Jewish ancestry also have about 3% (Northern Europe) till 8% (Italy) of what is called the Ashkenazi component on the JTest. A full Ashkenazi has ca. 20% Ashkenazi on the JTest, and also much East Med, West Asian etc. The Ashkenazi component on its own doesn't tell you anything if it isn't much more than the average of your main group of descent (see the spreadsheet on gedmatch for population averages).

I score 3.83% Ashkenazi on jtest, looking at the spreadsheet, it's about the same amount your average French Basque gets.

ianz91
10-03-2017, 05:11 PM
For example, in my case, I know I have 1/16 Jewish ancestry; the average for Dutch is about 3% Ashkenazi on this test, I get 4,5%. I also have more East Med than average; together these "excesses" would be attributable to my Jewish gg-grandmother.

I'd like to discuss this part quoted with you, if you don't mind. I don't want to take over the OP's thread. I'd like to show you my East Med, Red Sea, and Ashkenazi percentages I get from Gedmatch and tell me what you think. If I start a thread of my own can you reply there to help me? I would appreciate it.

JerryS.
10-03-2017, 05:27 PM
Wait what? You're saying that if someone scores 4.44% Jewish on jtest, they're actually not 4.44% Jewish, but 17%? Can you explain further? I'm confused.
Well they say 3% or less means little or no Jewish however 4% and higher would be an indication and using their mathematical equation of 25% being equal to 100% then 4 would be equal to 16 and so on I also agree with the East Med having to be part of that to add a little validity.

Pylsteen
10-03-2017, 05:40 PM
Well they say 3% or less means little or no Jewish however 4% and higher would be an indication and using their mathematical equation of 25% being equal to 100% then 4 would be equal to 16 and so on I also agree with the East Med having to be part of that to add a little validity.


You forget to subtract the default amount of Ashkenazi component in non-Jewish Europeans. Say, that you are 1/8 Jewish and 7/8 British, then you would get ca. 3,12% Ashkenazi component from the Jewish great-grandparent, but also ca. 2,7% (7/8 x ca. 3%) from your British side; this totals in ca. 5,82% Ashkenazi Component. You have to first subtract this Ashkenazi component from the non-Jewish side, only afterwards you can multiply by 4, otherwise this 5,82% would suggest a Jewish grandparent and not a great-grandparent.

For the question why Ashkenazi component is present in non-Ashkenazi: of course they share some European (a bit Germanic, Slavic, some southern European, maybe also some Near Eastern).

JerryS.
10-03-2017, 07:13 PM
You forget to subtract the default amount of Ashkenazi component in non-Jewish Europeans. Say, that you are 1/8 Jewish and 7/8 British, then you would get ca. 3,12% Ashkenazi component from the Jewish great-grandparent, but also ca. 2,7% (7/8 x ca. 3%) from your British side; this totals in ca. 5,82% Ashkenazi Component. You have to first subtract this Ashkenazi component from the non-Jewish side, only afterwards you can multiply by 4, otherwise this 5,82% would suggest a Jewish grandparent and not a great-grandparent.

For the question why Ashkenazi component is present in non-Ashkenazi: of course they share some European (a bit Germanic, Slavic, some southern European, maybe also some Near Eastern).

I have English that is also considered colonial American I guess I also have German that came to the United States in the mid-to-late 1800s and I have Italian that came to United States in the early 1900s. I have no known Jewish relatives it's never even come up in conversation there's never been a hint of it so is my 4.44% Ashkenazi on the Jtest an indication or not an indication? On some calculators I get Iraqi Jew in a small percent some also just list AJ which I assume is Ashkenazi Jew in a small percent. I've posted on other places my mdlp and dodecad and jtest results. If you can find them that would be great I appreciate your opinion I'm on a cell phone right now so I don't have access to my save documents.

McGowan
10-06-2017, 12:44 AM
Accuracy is subjective.

But a relative gets 23&me Jewish as 1.7%. Per Jtest they get 1.23% Ashkenazi. Their immediate relatives get southern European & no Jew. There's no Jewish names in relatives but they have Italian ancestry so 23&me likely can't distinguish between real Ashkenazi Jew & certain overlapping genetics at times.

JerryS.
10-06-2017, 11:12 PM
I think for the sake of academic integrity, the Jtest were to say up front what formula to use regarding their calculations.