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View Full Version : New Paper on Autosomal, yDna, and mtDna of Algerian Populations



Angela
28-09-15, 18:38
Genetic Heterogeneity in Algerian Human PopulationsThis is the link to the paper:
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.s010

"Our results of uniparental and autosomal markers in Algeria agree with the presence of ancestral components previously described in North Africa, attesting the genome complexity of Algerians (S8 Table (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.s010)). Concerning the Y-chromosome data, the highest frequencies are seen for the autochthonous North African lineages E-M81 and E-M78, this last one more frequent in Northeastern Africa where it has probably emerged [39 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref039)]; whereas the presence of the Middle Eastern Y-chromosome J1-M267 has been attributed to the Islamic expansion [40 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref040)]. In a similar way, the mitochondrial DNA analysis shows also different lineages in Algeria, already observed in North Africa: the North African lineages U6 and M1 that have been dated to Paleolithic times [41 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref041)–43 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref043)], the Eurasian H (related to the Neolithic expansion) and HV [29 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref029),44 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref044),45 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref045)]; and the sub-Saharan lineages (L). It has been suggested that the sub-Saharan lineages for both mtDNA and Y-chromosome reached very recently North Africa through the slave trade routes across the Sahara [16 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref016),46 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref046),47 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref047)]. Moreover, the autosomal genome-wide SNPs analysis also demonstrates the admixture of the Eurasian and African components in both Berber (Mozabite and Zenata) and non-Berber populations from Algeria in agreement with the general genetic North African landscape [3 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref003)].

The genetic structure observed in the Algerian analyzed groups is neither fully correlated with ethnic affiliation (Berber-Arab) nor with geography (coast vs. inland). It is noteworthy, however, that when we removed the Reguibate population from the Arab group, a significant differentiation was observed between the paternal gene pool profiles of Arabs and Berbers. This absence of differentiation between Arabs and Berbers is in agreement with what has been already observed in several North African populations by the analysis of different genetic markers, such as autosomal classical markers (such as HLA markers and GM allotypes) [6 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref006),12 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref012),14 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref014)]; autosomal STRs [7 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref007)]; Alu polymorphisms [8 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref008)]; Y-chromosome [13 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref013),48 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref048)]; and mtDNA analyses [11 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref011),12 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref012)]. As a result, it has been suggested that the Arabization of North African populations was mainly a cultural process rather than a demographic replacement of autochthonous groups [11 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref011)]."

This is also interesting:
"The distribution and frequencies of the North African, Eurasian and sub-Saharan components both in uniparental and autosomal markers is variable in each group, not only when comparing Berber and non-Berber, but also within linguistic groups. For example, some autochthonous North African haplogroups were not present in certain samples, such as the mtDNA U6 haplogroup that was absent in Algiers and present in only one individual in the analyzed Zenata group. In the same way, mtDNA haplogroup M1 is absent in the Zenata population. The absence of the maternal North African component in these groups, especially the Zenata Berbers, might be explained by extensive genetic drift and the remarkable high frequency of sub-Saharan lineages (~23% for the Y-chromosome E-M2 haplogroup and ~ 65% of mtDNA L lineages) in the Zenata sample. Our autosomal analysis also shows the close position of the Zenata group to the sub-Saharan populations, and the high variance in this sub-Saharan ancestry suggest that this group has experienced recent gene flow."

This is in accordance with comments that have been made on this site:
" The Berbers of North Africa are those North Africans who have retained at least a partial use of the Berber language and some degree of their tribal structure and their ancient culture. They are usually pretty endogamous. The level of SSA among them varies depending on the tribe and the country. Some, like the Mozabites, have quite a bit. Other groups look like they have a lot less, and some among them just look southern European.Likewise there are a lot of North Africans who don't primarily identify as Berbers. They also vary in terms of SSA admixture, with some urban, upper class people not showing a lot of SSA but most of them showing what is close to what the studies say, which is about 20-25% SSA ancestry."

The "SSA" like ancestry that this paper reports for some Berber groups is very high, whereas for other Berber groups like the Mozabites it is much lower, to the best of my recollection, than was found in prior analyses, where it is reported as about 20% in some studies. It may be because they use only the Yoruba as a reference population, and do not include some East African groups. The same effect is in operation in terms of the Palestinians, who get 10-12% SSA in some studies, but much lower here.

This is the table:
7436

Angela
28-09-15, 18:43
Here are the tables for yDna, mtDna and X chromosome:

7437

The yDna frequencies are in Table S2 and the mtDna frequencies are in Table S5.

Angela
28-09-15, 20:24
Here are the tables for yDna, mtDna and X chromosome:

7437

The yDna frequencies are in Table S2 and the mtDna frequencies are in Table S5.


One of the studies on NorthWest Oran shows about 12% R1b M269, but Oran was a huge slave trading center, and many of those slaves came from raids on the European coasts. It also was ruled for a good period of time by the Spanish.
https://en.wikipedia.org/wiki/Ora

In the Mozabites, 12.5% are M415, but it's a very small sample. As the authors point out:
"Although the Mozabites are descendants of the Zenata Berber group in North Africa, nowadays, the majority of the Mozabites form an isolated Ibadi Muslim group in Algeria. The Ibadi form of Islam evolved from the 7th century Islamic group known as the Kharijites in Irak. They reached Algeria and found a refuge within the isolated group of the Mozabites [51 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref051),52 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref052)]. Although both Zenata and Mozabite Berber groups are geographically close, their different genetic profiles suggest that Mozabites have been more isolated and received less gene flow than the Zenata, who show more admixture not only with sub-Saharan but also with Middle Eastern populations when analyzing autosomal markers."

This genetic isolation has resulted in a lot of genetic drift, so I don't know what conclusions we can draw from these numbers.

The Tizi Ouzou Berbers from the heart of Kabylia are interesting, as I don't know that they've ever specifically been studied. However, it's only a 15 person sample.
yDna
R1-M173:20%
E-M81: 53%
E-M34:13%
J-M304 (xJ2): 6%
F-M89: 6%

Salmon
28-09-15, 23:41
One of the studies on NorthWest Oran shows about 12% R1b M269, but Oran was a huge slave trading center, and many of those slaves came from raids on the European coasts. It also was ruled for a good period of time by the Spanish.
https://en.wikipedia.org/wiki/Ora

In the Mozabites, 12.5% are M415, but it's a very small sample. As the authors point out:
"Although the Mozabites are descendants of the Zenata Berber group in North Africa, nowadays, the majority of the Mozabites form an isolated Ibadi Muslim group in Algeria. The Ibadi form of Islam evolved from the 7th century Islamic group known as the Kharijites in Irak. They reached Algeria and found a refuge within the isolated group of the Mozabites [51 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref051),52 (http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138453#pone.0138453.ref052)]. Although both Zenata and Mozabite Berber groups are geographically close, their different genetic profiles suggest that Mozabites have been more isolated and received less gene flow than the Zenata, who show more admixture not only with sub-Saharan but also with Middle Eastern populations when analyzing autosomal markers."

This genetic isolation has resulted in a lot of genetic drift, so I don't know what conclusions we can draw from these numbers.

The Tizi Ouzou Berbers from the heart of Kabylia are interesting, as I don't know that they've ever specifically been studied. However, it's only a 15 person sample.
yDna
R1-M173:20%
E-M81: 53%
E-M34:13%
J-M304 (xJ2): 6%
F-M89: 6%

- Vandals/Vandals who converted to Islam
- Slave traders
- Barbary Pirates
- Regular old fashioned merchants, sailors throughout history.
- European soldiers from one of many military campaigns Europeans have had in North Africa in the past few thousand years.
-Andalusian Mawali
-Andalusian Muladi descended from Iberian men


It's on the coast.

Hauteville
20-10-15, 18:22
Ssa admix came from medieval slaves?

Drac II
21-10-15, 09:58
Ssa admix came from medieval slaves?

Probably not totally, but very likely the majority of it. It is simply impossible to overlook the role of the medieval and early modern (in some Muslim countries slavery of black Africans in fact goes on even today) sub-Saharan slave trade in North Africa and the Middle East. The emerging European empires of early modern times in fact got the idea of enslaving sub-Saharan Africans and dehumanizing them to justify their slavery from the Muslims and their empires, who had been doing just that long before them. Trying to deny the impact that these millions of sub-Saharan slaves (according to Steven Carol the Islamic slave trade was responsible for anywhere around "17 million to more than 28 million" enslaved black Africans) had on the current population make-up of the Muslim world is about as unrealistic as trying to deny it for Brazil, Colombia, Venezuela, the Guianas, Haiti, Dominican Republic, Cuba, USA, etc. No one in his right mind would think that the importation of millions of slaves did not have an impact on the population make-up of any of these New World nations. People of black African descent have become a very visible population in all of them. Same in the Muslim world.

Hauteville
30-10-15, 20:03
Probably not totally, but very likely the majority of it. It is simply impossible to overlook the role of the medieval and early modern (in some Muslim countries slavery of black Africans in fact goes on even today) sub-Saharan slave trade in North Africa and the Middle East. The emerging European empires of early modern times in fact got the idea of enslaving sub-Saharan Africans and dehumanizing them to justify their slavery from the Muslims and their empires, who had been doing just that long before them. Trying to deny the impact that these millions of sub-Saharan slaves (according to Steven Carol the Islamic slave trade was responsible for anywhere around "17 million to more than 28 million" enslaved black Africans) had on the current population make-up of the Muslim world is about as unrealistic as trying to deny it for Brazil, Colombia, Venezuela, the Guianas, Haiti, Dominican Republic, Cuba, USA, etc. No one in his right mind would think that the importation of millions of slaves did not have an impact on the population make-up of any of these New World nations. People of black African descent have become a very visible population in all of them. Same in the Muslim world.
This is what I think indeed although I don't know how many (in percentage) sub-saharan slaves were brought to North Africa.

MOESAN
06-01-16, 15:49
to Angela: OK for your supposition of East-African not included in the analysis: it could explain the curious position of Mozabites, far from Yoruba, but far from Basques and a bit far from Palestinians.
to all:



the study about the Berbericand Arabic populations of Algeria has shown interesting results. Theyhave been discussed already so I add just a few remarks :
1- the Zenats (Zenati?)Berbers from Southern Algeria not only are shifted towards Yorubapeople's DNA but their autosomes as well as their X chromosom show avery widely spred spectre from other Algerians DNA to close to Yorubapeople, proof of a still evolving process f crossings and not anancient stabilized one. Thta is easy to state according toindividuals phenotypes in these regions. The X chromosom (not mtDNA)confirms it is for the most mediated through the wives, what is beseen too among Yemenites.
2- compared to autosomoes DNAthe X DNA shows a bigger variation in ALL the populationsobserved in the study, eve among populations relatively homogenousfir auDNA : with the X, the « barriers » betweenpopulations seem less strict, and even the Basques are in contact toPalestinians – Palestinians overlap with Algerians, Mozabitesoverlap with Algerians and so on ; only the Yoruba, spite lesshomogenous than for auDNA, form a distinct group : they« loaned » NO female to the others, what is the not thecase on the opposite direction (SSA Wives taken by Arabs andBerbers).
& : it recalls me anold survey about the X-chromosom (not only the mtDNA) in the wholeMediterranean world (Levant comprised) which concluded to the bigrole of females in the exchanges in Mediterranean, very lesscompartimented than the Y-DNA.
Females travelled often lessfar than SOME of the males, but did it all the time from place toplace ; a possible exception : the enslaved females whocould go very far.

a derived conclusion of mine is that the most of the SSA introgression in the Arabic world is more the result of recent crossings/matings than the result of ancient slavery. The coastal regions of North Africa where are big towns and where we ought to find slaves descendants are by far less southsaharianlike and I don't think it's due to "white" blood - whatever the mode: slavery or colonization - come there to "wash" the previous effects of african slavery.