An interesting blog post from 23andMe:
In an update to that work, our researcher Kasia Bryc found that about about 4 percent of whites have at least 1 percent or more African ancestry.and:
Although it is a relatively small percentage, the percentage indicates that an individual with at least 1 percent African ancestry had an African ancestor within the last six generations, or in the last 200 years. This data also suggests that individuals with mixed parentage at some point were absorbed into the white population.
Looking a little more deeply into the data, Kasia also found that the percentage of whites with hidden African ancestry differed significantly from state-to-state. Southern states with the highest African American populations, tended to have the highest percentages of hidden African ancestry. In South Carolina at least 13 percent of self-identified whites have 1 percent or more African ancestry, while in Louisiana the number is a little more than 12 percent. In Georgia and Alabama the number is about 9 percent. The differences perhaps point to different social and cultural histories within the south.
Previous published studies estimate that on average African Americans had about 82 percent African ancestry and about 18 percent European ancestry. But in self-identified African Americans in 23andMe’s database, Kasia found the average amount of African ancestry was closer to 73 percent.I don't think that is necessarily the average percentage in the general African American population as the subset of African Americans who take 23andMe tests may not be representative (e.g., it may come more from cities where African Americans may have more opportunity to admix with European Americans).
and:
On average Latinos had about 70 percent European ancestry, 14 percent Native American ancestry and 6 percent African ancestry. The remainder ancestry is difficult to assign because the DNA is either shared by a number of different populations around the world, or because it’s from understudied populations, such as Native Americans. Obviously that large “unassigned” percentage means that those “averages” could be higher. As with African Americans, looking at the regional and state-to-state numbers for self-identified Latinos, the differences are striking.
...23andMe may have a couple of orders of magnitude more sampled individuals than anything that appears in most published studies and it's great to see this being put to good use.
For example, some Latinos have no discernible Native American ancestry, while in others have as much as 50 percent of the ancestry being Native American. Latinos in states in the Southwest, bordering Mexico — New Mexico, Texas, California and Arizona — have the greatest percentage of Native American ancestry. Latinos in states with the largest proportion of African Americans in their population — South Carolina, Louisiana and Alabama — have the highest percentage of African Ancestry.
It'd be great if someone at 23andMe did some more analyses over their huge database. I can only imagine what a flashPCA with half a million individuals from around the world would look like; even if it told us nothing new about human history it would be quite a cool picture to look at.
24 comments:
they didnt use haplogroups!
"On average Latinos had about 70 percent European ancestry, 14 percent Native American ancestry and 6 percent African ancestry. The remainder ancestry is difficult to assign because the DNA is either shared by a number of different populations around the world, or because it’s from understudied populations, such as Native Americans. Obviously that large “unassigned” percentage means that those “averages” could be higher. As with African Americans, looking at the regional and state-to-state numbers for self-identified Latinos, the differences are striking.
...
For example, some Latinos have no discernible Native American ancestry, while in others have as much as 50 percent of the ancestry being Native American. Latinos in states in the Southwest, bordering Mexico — New Mexico, Texas, California and Arizona — have the greatest percentage of Native American ancestry. Latinos in states with the largest proportion of African Americans in their population — South Carolina, Louisiana and Alabama — have the highest percentage of African Ancestry."
We could have made those deductions based on other studies since in the southwest the Latinos are mostly from Mexico and Central America. In the southeast they are mainly Latinos from Cuba, Puerto Rico, Dominican Republic, Colombia, Venezuela and so on.
Native American origins from whole-genome and exome data (Gravel et al. 2013) states "Estimated Native American ancestry is 48% in MXL, 25% in CLM, and 13% in PUR. and it provides an admixture graph of of the components of Native American, West African, and European among Columbians, Mexicans, and Puerto Ricans.
http://dienekes.blogspot.com/2013/06/native-american-origins-from-whole.html
In Reconstructing the Population Genetic History of the Caribbean (Andrés Moreno-Estrada et al. 2013) there is k=3 admixture graph of those same components among Cubans, Haitians, Dominicans, Puerto Ricans, Colombians, Hondurans, and Mexicans as well as some European and Native American groups.
http://dienekes.blogspot.com/2013/11/population-history-of-caribbean.html
As can be seen from the previous two studies Mexicans have the highest amount of Native American ancestry, but some Mexicans have a relatively low amount of it. People from the islands have a higher amount of African ancestry. The only thing missing from the two studies, that was included in the 23andme report, are the overall percentages of African and European components of all Latinos. However, the 23andme report did not give a breakdown of percentages of components by country for the Latinos.
"I don't think that is necessarily the average percentage in the general African American population as the subset of African Americans who take 23andMe tests may not be representative (e.g., it may come more from cities where African Americans may have more opportunity to admix with European Americans).
"
This is my growing up in urban America for 16 years opinion, and I have no statistics. Prior to maybe the last 40-50 years African Americans and European Americans almost never mixed and if they did it was a phenomenon and looked down by blacks and whites. So if there is an African American with post slavery European ancestry they would probably know. The 1980's was really when you first saw black-white inter marriage and it was still controversial. Besides black-white inter marriage is very very very very rare in America still today.
Almost all European ancestry in African Americans I think is from slavery times. Mainly from rape of slave women(which was more common than most think). Many slang words meaning half white half black come from slavery times like mulatto. I had to read the narrative of Frederick Douglass for school this year and he made it clear rape of slave women was common and said other slaves said his father was a white man. There were also willing white-black relationships that's probably why 23andme says 13% of white Americans in south Carolina have 1% African ancestry.
This is just my guess white-black inter marriage was probably totally abolished by at least whites, so all mulatto children would have been born in wedlock(or secret marriages, I have heard rumors about Thomas Jefferson having a secret black family). If a black woman gave birth to a mulatto child it would stay in the black community if a white woman gave birth to a mulatto child it would stay in the white or black community. That's probably why African Americans have so much more European ancestry than white Americans have African ancestry, because it was most oftenly white men raping black slave women and even if a white woman gave birth to a mulatto child that child was put in the black community. I have heard that there is typically north-west European Y DNA in African Americans but I have never heard of typical west Eurasian mtDNA in African Americans.
I think it is pretty safe to assume from colonial times to the end of slavery the majority of American citzens were of British(including Scottish, English, Welsh, and Cornish) or Irish ancestry. If not that they were most likely of German or Dutch ancestry. Irish, British, German, and Dutch differ by very little in admixtures. All African Americans that I have known have surnames in the English language, which is not a surprise since in admixtures it looks like there is a little north-west European(most similar to English) in them and takes up about 15-20% of their total percentages.
For Hispanics, I definitely think Mexicans have the highest amount of native American ancestry. They are the darkest skinned, widest faced, widest nosed, and shortest and stockiest of Hispanics I have seen. I have seen some Mexicans who look no different from depictions of native Americans from around the United States or depictions of ancient Mayans and Aztecs. Puerto Ricans on the other hand tend to have pale skin and overall west Eurasian looking faces and are taller. They definitely don't look like Spaniards though their native American and African ancestry is probably why. Actually many Puerto Ricans have snow white kind of dead looking skin(no offense). Some Hispanics resemble paintings of conquistadors like Hernado Cortez or other paintings of Spaniards from the 1500's I have seen. Some Puerto Ricans I have seen have obvious mixed African, Iberian, and native American ancestry.
Hispanics know probably the least about their ancestry out of all American ethnicities. In my history book it says the ancestors of Latin Americans like the ancestors of European and African Americans came during colonial times. Some Hispanics think of themselves as Hispanic they have no idea that they have Iberian, Native American, and west African ancestry.
I try to tell Hispanics they are part native American but they never believe me. There are some who look to have no Iberian or African ancestry, and during class the teacher will show pictures of native Americans and the Hispanic kids are so blind they don't notice the similarities. They have to think where do we get our brownish skin, Spainish(no), Africans(no), Native Americans(yes).
Some Hispanics who obviously are of nearly pure Spainish ancestry, seem to have no idea. They critize what Europeans did to native Americans and west Africans and don't realize they are nearly 100% Spainish.
More pseudo-science from a commercial lab trying to sell a product and get headlines.
Don't get me wrong; some of this is valid and it mirrors prior scientific studies. For example, the general notion that African Americans in the South have less white admixture than those in other states. But a history book and a glance at skin color could tell us that. There was less intermarriage in places of high prejudice. Not exactly shocking.
It's the claims of precision that are absolute malarkey.
I hope they sell lots of tests to suckers who think it is possible to discern that one's ancestry is 98.23578654220364528 percent of something.
Anyone trying to claim that precision (or anything even close) given this technology is a charlatan.
Consider the case of a Central American who gets tested. He might self-identify as Hispanic or perhaps White, depending on his proclivities. (More on that problem below).
This person might have Spanish blood.
The Spanish blood might appear slightly North African and perhaps a tiny bit Sub-Saharan African.
(Refer to Haplogroup E).
However, there is no way to discern if those genes entered his genome 6000 years ago (i.e., before modern concepts of ethnicity).
After all, Hg E and similar genes were present in Iberia a long, long time ago. Ancient DNA finds have confirmed this.
OR those genes could have entered his gene pool by North African marauders, during the Muslim conquest.
Or by an introgression of African DNA from a black slave during the Spanish occupation of Central America.
And the way labs like this ID genes are from those who self-identify.
As you can see, it gets complicated. It's not reliable. It's horse manure.
That Spaniard might have genes that have been Spanish for 6000 years, yet told that they are "North African."
Remember, such designations are MEANINGLESS without some sort of TIME designation too. IE, "recent North African."
We ALL came from Africa at some point. Almost ALL European genes came through the Middle East at some point.
Thus, unless one specifies time and has wonderfully accurate data, this whole exercise is a fool's errand.
African ancestry in the white population is nothing new. It's just kept from the general public.
http://www.yalelawjournal.org/the-yale-law-journal/essay/the-secret-history-of-race-in-the-united-states/
I wonder why they did not discuss native American ancestry among European-Americans, which can be appreciable in many regions such as Appalachia and the upper Midwest.
I personally find their ancestry algorithms suspect. My family has been admixing since the early 17th century, and our Native American ancestry is well documented. I have typical Native American characteristics such as sinodonty and lactose intolerance, and many of my relatives are easily recognizable as "Native American", yet the Ancestry by DNA test I took as well as the National Geographic Genomics project failed to pick up any Native American DNA at all! I'm going to send in my 23andMe sample soon, and maybe they will do better.
On a related note - many people outside of the US may not be aware of it, but the US Food and Drug Administration, acting under pressure from the powerful physicians' guild, the American Medical Association, has classified 23andMe and other generics tests as "medical devices" and has barred genetics companies from reporting on genes thought to be associated with diseases or conditions. This may discourage people from taking these tests, reducing its value for genetics research.
@mooreisbetter. Spaniards, who also call themselves Hispanics, have a small amount of African ancestry. It shows up in the in the k=13 analysis spreadsheet at http://dodecad.blogspot.com/2012/10/globe13-calculator.html
It also shows up in the k=3 of Spain of the study Reconstructing the Population Genetic History of the Caribbean (Andrés Moreno-Estrada et al. 2013) see http://dienekes.blogspot.com/2013/11/population-history-of-caribbean.html and open the image in a new window or tab which takes you to http://2.bp.blogspot.com/-0Iom7wG_y5U/UoWCzElLolI/AAAAAAAAJZQ/G__wB1wl9FQ/s1600/journal.pgen.1003925.g001.png Do you see the tiny amount of green in Spain, Portugal, Italy and Greece?
That small amount is from the combined amount of the possible scenarios you mentioned of it being from 6,000 years ago, North African marauders, and the Muslim conquest. Ever since boats were able to go to Spain there have been people with African ancestry going to Iberia.
Regardles, the very small amount of African ancestry in Spaniards is not enough to create the very large amounts of African ancestry among the Cubans, Haitians, Dominicans, and Puerto Ricans. The study does not contain malarky. It is saying what most people that study Iberian and Latin American history already know, which is that there are a lot of living descendants of African slaves in Latin America.
Latin America had a caste system that was largely based on ethnicity but people could change their social status and obtain a different ethnic label. See http://en.wikipedia.org/wiki/Casta I've seen the change with my own ancestors as well as with the ancestors of many other people. The records still exist and we can see when our ancestors were labeled as Español, Mestizo, Mulato, Indio, Tresalba, Coyote, or other. The people that had the Español label supposedly had 7/8 or more of European ancestry and they had a higher status but the label wasn't always accurate. Even so, most of the people with a significant number of mulatos in their ancestry have a higher than normal amount of African markers in their autosomal DNA tests. It does not matter how a person self identified and it does not matter that Spaniards already had African ancestry. It does not matter that almost all European genes came through the Middle East at some point. Belonging to a specific haplogroup has no bearing. It does not matter if a Latino looks 100% European. The mulato ancestry, which is from African slaves, shows in the autosomal markers in their Latino descendants. They can't hide it. You could maybe subtract 1% from the 6% reported, if they didn't take into consideration the 1% among Spaniards, but that is all. That still leaves 5% African ancestry on average among Latinos. Remember, these are average population studies.
There is no malarky or horse manure. Only a HUGE misunderstanding on your part.
@Daniel Szelkey
Autosomal markers can find ancestry that haplogroups can't.
@barakobama
There are a lot of Spaniards that have brown skin. You should learn Spanish and visit Spain sometime.
@AD Powell
Yes, there are many cases of hidden ancestry. Hopefully we can all mature enough to accept this at some point.
http://en.wikipedia.org/wiki/Passing_%28racial_identity%29
http://www.youtube.com/watch?v=GZLrw19zvik
@Mark D
You are using personal experience only. Having the people that you know tested would be unlikely to throw an average of thousands of people off. There are many people that fit what you see that did have an interest in getting tested and purchased the test. Either way, the study Reconstructing the Population Genetic History of the Caribbean (Andrés Moreno-Estrada et al. 2013) was much better.
"I have never heard of typical west Eurasian mtDNA in African Americans."
One of my American 23 and Me relatives traces her ancestry back many generations back to Barbados. She has European mitochondrial DNA. We think she might be descended from a marriage between a British indentured servant and a slave/freed man. But she has not been able to find them yet.
I don't think it is a futile gesture. Its hard to be a racial purist if you find out that great great grandad was that thing that you hate. And hidden African ancestry is common in precisely the areas where racism is a problem.
The frequency of non-sub-Saharan haplogroups in Jamaican athletes and Jamaican controls was similar (1.87% and 1.71%, respectively) and lower than that of African-American athletes and African-"American controls (21.01% and 8.19%, respectively). There was no significant difference in total haplogroup frequencies between Jamaican athletes and Jamaican controls (P=0.551 ± 0.005); however, there was a highly significant difference between African-American athletes and African-American controls (P less than 0.001). "
Apologies for the back to back.
Non African mitochondrial DNA in African Americans is not all that low. Around 8% on average.
Mooreistbetter, I agree most of this stuff is already known by people who actually care about history because it happened only within the last 500 years. The whole Spainish-Native American-African thing Is pretty well known in Latin America(but not in many Latino Americans). 23andme should not be using the same strategy with new world ethnicities as they do with old world ethnicities. If I remember correctly Geno 2.0 says European ancestry in Hispanics is from white American mixing and African ancestry rom black American mixing. People create myths because they use the same strategy they do with much more ancient old world ethnicities.
Also when they say European in Hispanics I am pretty sure they just mean west Eurasian. Anything west Eurasian like in Hispanics they qualify as European.
There hasn't been enough white-black mixing in the north that could have effected every northern African American and besides most of northern African American's ancestry was in the south just 100 years ago or so. White-black mixing is very very very rare and has mainly occurred in only the last 30 years.
"However, there is no way to discern if those genes entered his genome 6000 years ago (i.e., before modern concepts of ethnicity). "
What?!! There have always been ethnicities/families/tribes/cultures/etc. I don't know much about Y DNA E1b1b in Iberia but I do know V13 and other subclades did not come from north-west Africa they came with early farmers from the near east. There may be ways to discern with autosomal DNA when the mixing occurred.
" There was less intermarriage in places of high prejudice. Not exactly shocking.
"
Being prejudice is not the same as being raciest, people get those words confused oftenly. All Prejudice means is pre judge. Everyone is prejudice at times.
Mark D, so you think the more Spainish Hispanics are the richest ones in America and taje these tests more than any other hispanics. I think this is just an assumption white=rich and minority=poor. Besides you should look at studies which sampled random Hispanics for no money and the results are not any different. Native American-Iberian-west African mixing in Latin America is only at the oldest 400-500 years old so even in Hispanic families and small towns there is variation in percentage of ancestry from those groups.
African ancestry in the white population is nothing new. It's just kept from the general public.
It is also pretty rare with only about 4% of whites having at least 1% or more African ancestry. That means that 96% of whites have less than 1% or no African ancestry.
@Gary Moore
I imagine they are hoping to avoid controversy with the NA results. What do you do with the Iroquois for example, who probably have pre-Columbian European DNA. Not to mention folk who know they have native origins get very upset when you tell them that you can't find it.
Try Doug MacDonalds (direct) analysis. He was able to detect NA and African ancestry ONLY in my American lines and not a trace in the UK lines. I found it sensitive and believable.
I agree that the 70% European figure for Hispanics is probably related to the fact that 23andme customers tend to have higher SES. The correlation between whiteness and SES among Hispanics is quite obvious to anyone with experience in this community.
FWIW, I am an American Hispanic and my autosomal percentages are approximately as follows:
1/2 European
3/8 Native American
1/8 West African
My father was from El Salvador and was almost certainly more than half Native American. My mother is from Puerto Rico and although she and her sisters all look European, she must be where I get the bulk of my African ancestry from. She's the type of Puerto Rican that some commenters referred to as milky white. After so many generations of race mixing in Puerto Rico, phenotypes are quite different from what you would expect from the same autosomal proportions in recently admixed individuals. My maternal grandmother had obvious African ancestry that did not show up in any of her children. By American standards, she would have been considered black.
@Dospaises - " Either way, the study Reconstructing the Population Genetic History of the Caribbean (Andrés Moreno-Estrada et al. 2013) was much better."
Agreed. I favorably commented on the paper last November, http://dienekes.blogspot.com/2013/11/population-history-of-caribbean.html
Nevertheless, there is no substitute for large and representative sample sizes that match targeted demographics. Too often the samples researchers obtain are too few and too skewed. Even those involved in the 1000 Genomes project acknowledged how "white" their PUR samples were.
@barakobama - "so you think the more Spainish Hispanics are the richest ones in America and taje these tests more than any other hispanics. I think this is just an assumption white=rich and minority=poor."
Yes, I do. My opinion is based on a career of studying the socio-economic stratification of immigrants from Latin American and Caribbean countries in South Florida. Dospaises (Two Nations) is certainly aware of this "caste" system. Do you really think that the poor immigrant recently arrived in this country, and who can barely speak English, will even know about let alone pay $99 for the 23andMe DNA test?
The amount of African ancestry in whites would vary depending on region:
http://www.huffingtonpost.com/2012/05/24/melungeon-dna-study-origin_n_1544489.html
We think she might be descended from a marriage between a British indentured servant and a slave/freed man
Pregnancy as a result of rape is also a possibility.
Having no discernible sub Saharan ancestry does not mean there was no admixture event in the past.
Believe what you want Ponto. I am just pointing out what the evidence shows.
Annie Mouse: Thanks for the tips. I'll look into that test.
If you read the disclaimers for many of the popular DNA testing services, they admit the accuracy of their tests fall off drastically after three of four generations. I also suspect they do not handle the analysis of genetic profiles resulting from many generations of admixed people marrying other admixed people, as in the case of mestizos in Latin America or racially mixed people in the US, and may underpredict the amount of NA ancestry. I also suspect that algorithms for predicting ancestry may have been "tweaked" as a result of some researchers concluding that the NA ancestry found in Europeans must have been a "mistake".
DNA testing can serve a useful role in informing medical treatment. My sister lost both her lower first molars despite root canal procedures, and we now now that it was because she had the typical Native American trait of having a third molar root on those teeth that were overlooked by her endodontist. I was lucky because my endodontist was Chinese and recognized the problem right away.
@ Unknown
The story was about Latinos in the U.S. not about Latinos around the world. Argentinians, which is mostly what you refer to, are only 0.5% of Latinos in the U.S. http://www.pewhispanic.org/2013/06/19/diverse-origins-the-nations-14-largest-hispanic-origin-groups/
Any mention of Latino groups was based on the most populous groups of Latinos in the U.S. and if you read my previous posts you can see other reports of the genetic makeup of the most populous Latino groups in the U.S. including Cubans, Dominicans, Puerto Ricans, Colombians, Hondurans, and Mexicans. Better yet, I'll include the link again - http://dienekes.blogspot.com/2013/11/population-history-of-caribbean.html
In those countries the European immigrants were mainly Spaniards and Portuguese with a small amount of Europeans from other countries. No one denies that there were other Europeans, but by far a majority were from Iberia and 66% were from southern Spain, Portugal, and the Canary Islands. The northern Spaniards and Basques had to marry into the southern Spanish and Portuguese families over the past 500 years in Latin America. Therefore, the DNA of northern Spaniards was mixed with southern Spaniards which introduced the small amount of African ancestry that southern Spaniards and Iberians have on average.
Galicians weren't reported in the 1,000 Genomes but Catalans were and they have 0.3% African ancestry, on average, so there was some African admixture there.
You also need to keep in mind that the story and the responses were about averages and not about exceptions which is what you want to point out.
Argentina on average is 65% European (95%CI: 63–68%), 31% Indigenous American (28–33%) and 4% African (3–4%). See http://dienekes.blogspot.com/2012/04/admixture-in-different-regions-of.html
Another study shows that the breakup of Argentinian mtDNA http://dienekes.blogspot.com/2011/08/migration-and-argentinean-mtdna.html
The two previous studies of Argentina go to show that what happened in Latin America also happened in Argentina on average which was that a majority of the immigrants were men and most had to marry, or had children out of wedlock, with women who had mixed ancestry.
DNA testing is making it to where your compatriots can't hide their mixed ancestry and try and revise history. You and some others are the exception and not the rule. It's important people learn the difference. On average your countrymen are a mix of European, Native American, and African like the rest of Latin America.
@Dospaises: The first line of the study you refer us to says "99 AIMs are probably not good enough to obtain accurate admixture estimates, but they are probably sufficient to highlight real differences in the origins of different Argentinean sub-populations."
All too often in the area of DNA research like this, people have strong biases as to what they want the ancestry of some population to be or not to be, and there is at this point often some study or some interpretation of a study that can be found to support whatever one wants to believe. You have to dig a little deeper to get any sense of how reliable or conclusive the data from any study is.
Too often in these discussions we see eye catching declarations with links to legitimate looking research papers that are purported to provide strong support for the claim being made. Too often they in fact provide something along the lines of "here is an ambiguous, contested, and inconclusive study, but it is in a journal and it supports what I'd like to be true so let's regard it as 'proof'" etc.
There's just way too many armchair genealogists and geneticists in the blogosphere these days tossing around terms they barely understand (the classic being "haplogroup") and enough garbage data around that one can find studies to 'support' just about anything they want to be true. There is no topic that provides such an abundance of examples of cherry picking, quite mining, and selection bias as these online discussions of genetics and genealogy. It's become such that witnessing the participant's various and sundry biases so obviously at play is more interesting than the research itself.
Iroquois have no European DNA in pre-columbian times, never did. That's a fallacy that most white Americans are promoting. The Iroquois have the same Native American indigenous ancestry that all NAs share. There were no Europeans in America at that time.
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