Another study shows Nubians are more genetically related to Cushitic speakers than Nilo Saharans

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In this study we present an extensive genome-wide data set characterizing East African human genetic diversity in populations from Sudan, South Sudan and Ethiopia. We further analyse the Nilo-Saharan ancestral component within the variation of South-Saharan Africans.

Nubians are the only Nilo-Saharan speaking group that does not cluster with groups of the same linguistic affiliation, but with Sudanese Afro-Asiatic speaking groups (Arabs and Cushitic Beja) and Afro-Asiatic Ethiopians.

Y-chromosome and mitochondrial DNA studies reported Nubians to be more similar to Egyptians and Ethiopians than to other Nilo-Saharan populations.....


A random subset of 18 individuals from each population was selected to avoid sample size bias. Columns represent individuals, where the size of each colour segment represents the proportion of ancestry from each cluster. Although k = 3 is the statistically supported model, here we show the results from k = 2 through k = 5 as they explain several ancestral components: North African/Middle Eastern (dark blue), Sub-Saharan (light blue), Coptic/Cushitic (dark green), Nilo-Saharan (light green) and Fulani (pink). MKK = Maasai from Kinyawa, Kenya; LWK = Luhya from Webuye, Kenya; YRI = Yoruba from Ibadan, Nigeria.

Populations from the North-East cluster: Beja, Ethiopians, Arabs and Nubians (Table 2) may be explained as admixture products of an ancestral North African population (similar to Copts).

Nubians are the only Nilo-Saharan speaking group that does not cluster with groups of the same linguistic affiliation, but with Sudanese Afro-Asiatic speaking groups (Arabs and Beja) and Afro-Asiatic Ethiopians (Supplementary Fig. S1a). Y-chromosome and mitochondrial DNA studies reported Nubians to be more similar to Egyptians than to other Nilo-Saharan populations1,8: Nubians were influenced by Arabs as a direct result of the penetration of large numbers of Arabs into the Nile Valley over long periods of time following the arrival of Islam around 651 A.D20.

Interestingly, our analyses shows a unique ancestry for Sudanese Nilo-Saharan speaking groups (Darfurians and Nuba) related to Nilotes of South Sudan, but not to other Sudanese populations or sub-Saharan populations (Fig. 3). This ancestral component is not present in places where the Bantu expansion left a strong footprint and creates a different genetic background that is not found among most African populations. Tishkoff et al.5. reported a common ancestry of Nilo-Saharan speaking populations. We also found this relationship of Nilo-Saharan Sudanese populations with other Nilo-Saharan populations from Kenya (Maasai), but not as strong, as Maasai show their own genetic component at k = 6, which is different from the Sudanese component (Supplementary Fig. S7) and do not cluster with our Nilo-Saharan speaking populations. In a previous Y-chromosome study8, most Nilo-Saharan speaking populations, except Nubians, showed little evidence of gene flow with other Sudanese populations.

The presence of the core of Nilo-Saharan languages in the confluence of the two Nile rivers suggests that the Sudanese region is the place of origin of the Nilo-Saharan linguistic family despite their fragmented distribution, as shown by the location of the Nubian language21,22. It is interesting to note that Nuba populations constitute an homogeneous group, even if some speak Kordofanian (of the Niger-Kordofanian family) and others different languages of two branches of the Nilo-Saharan family. Their genetic composition denotes their Nilo-Saharan origin, with linguistic replacements in some groups.

Population displacement, whether it is followed with cultural or genetic exchange with local populations, would explain why not every Nilo-Saharan speaking group has this genetic component (as is the case of Nubians) and not every population that has it is mainly formed by Nilo-Saharan speakers (as is the case of Niger-Kordofanian speaking Nuba).



References:
https://www.nature.com/articles/srep09996/tables/2
https://www.nature.com/articles/srep09996



 
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srep09996-f2.jpg




Plot shows a) PC1 and PC2 and b) PC2 and PC3 and the variation explained by them. Sudanese populations cluster in four groups according to their geographic location, with PC1 representing a north-east to south-west axis in East Africa. Populations not genotyped in this study are shown with grey filled symbols. MKK = Maasai from Kinyawa, Kenya; LWK = Luhya from Webuye, Kenya; YRI = Yoruba from Ibadan, Nigeria.
 
Results

Population Structure
We applied a principal component analysis (PCA) to investigate the population structure of the new populations genotyped in this study from the Sudanese region (Supplementary Fig. S1a). PC1 (3.56% of the variation) follows a North-South cline and separates populations inhabiting the region between the Nile River and the Red Sea (Nubians and Arabs along the Nile, Beja and Ethiopians along the coast) from Darfurians and Nuba of South-West Sudan, and Nilotes of South Sudan. Copts are a separated group close to the North-East populations, in a more outlier position: they are the extreme of the northern genetic component. PC2 (0.7%) separates the nomadic Fulani from the other populations.


Next, we combined our new populations (140 K data set) with previously studied populations of special interest for this analysis: Qatar12, Egypt13, and three sub-Saharan populations (Luhya, Yoruba and Maasai) from 1000 Genomes Project14 to have external references both in the north and south of the Sudanese region. This new data set contains 14,343 SNPs (14 K data set). Even if the number of SNPs in this second set is small, it is enough to differentiate components in the African genetic landscape15. Fig. 2 shows a PCA of this extended data set, where East African populations are distinct from both sub-Saharan and North African populations. PC1 (6.08%) separates between populations from North Africa/Middle East and sub-Saharan Africa (Fig. 2a). Copts are closer to North African and Middle East populations but remain as a separate cluster when PC2 is considered. PC2 (1.46%) along with PC1 separate the two homogeneous clusters of North-East and South-West populations: Nubians, Arabs, Beja and Ethiopians on one hand, and Nuba, Darfurians and Nilotes on the other. PC2 separates all Sudanese and Ethiopian populations from the rest. PC3 (0.56%) differentiates West-African populations (Fulani and Yoruba) from Sub-Saharan East African populations (Maasai) (Fig. 2b). Both PC analysis using data sets with different number of SNPs preserve the topology of the populations. As expected, with a low number of SNPs we observe a higher intra-population variation (Supplementary Fig. S1b).
 
Pairwise FST statistic, a measure of global population differentiation, confirmed the PCA clustering (Supplementary Table S2, Supplementary Fig. S5). Populations geographically close had low average FST values, even though population-specific characteristics were emphasized by excluding population outliers (Supplementary Fig. S4). The lowest average FST (0.003) was found both in the pair Arabs and Nubians, located at the Nile River Valley, and in the pair Beja and Ethiopians, located at the coast. Among North-East populations, Nubians had the highest FST values when compared with Beja and Ethiopians (average FST of 0.006 and 0.007 respectively). South-West populations showed higher population differentiation among themselves than North-East populations. When comparing North-East populations with South-West populations, all comparisons have a high FST (between 0.044 and 0.054). Copts, with a strong individual heterogeneity, are more similar to Arabs (FST = 0.019) than to any other East African population. Copts and South-West populations are the most distant populations (FST > 0.1). Fulani had on average lower FST values when compared to South-West (Nuba, Darfurians and Nilotes) than to North-East populations (Nubians, Arabs, Beja and Ethiopians). These values show a complex situation beyond the simple North African versus Sub-Saharan Africa main differentiation.
 

World

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The Copts are also closer to Sudanese Arabs/Nubians/Bejas/Ethiopians than they are to Egyptians/Qatar(who are closely related).

Bearing in mind that Copts are the closest representation of the Ancient Egyptians, doesn’t that prove that modern day Muslim Egyptians aren’t that related to them?
 
The Copts are also closer to Sudanese Arabs/Nubians/Beja/Ethiopians than they are to Egyptians/Qatar(who are closely related).

The only issue with the Copts is the majority are Haplogroup J which indicates Middle Eastern ancestry.
 

Apollo

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The Copts are also closer to Sudanese Arabs/Nubians/Bejas/Ethiopians than they are to Egyptians/Qatar(who are closely related).

Bearing in mind that Copts are the closest representation of the Ancient Egyptians, doesn’t that prove that modern day Muslim Egyptians aren’t that related to them?

Look at the K=2. The Copts are full or near full Eurasian.. the Eurasian component and African component have large genetic distance (split over 70,000 years ago). So Copts are still closer to Arabs than to Nubians or Horners because they have much less Sub-Saharan.
 

World

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Look at the K=2. The Copts are full or near full Eurasian.. the Eurasian component and African component have large genetic distance (split over 70,000 years ago). So Copts are still closer to Arabs than to Nubians or Horners because they have much less Sub-Saharan.
srep09996-f2.jpg


Doesn’t look like it here.
 

World

VIP
DNA tribes result of a typical Egyptian Copt:


She's closer to Bedouins, Arabs, Yemenite Jews etc than to Nubians or Horners.
So your proof is a random YouTube video, but the peer reviewed scientific report in the OP is wrong?
 

Apollo

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So your proof is a random YouTube video, but the peer reviewed scientific report in the OP is wrong?

People have downloaded those samples and ran them through other analyses. Copts are more Middle Eastern than Muslim Egyptians. This is a fact. Google is your friend.
 
Look at the K=2. The Copts are full or near full Eurasian.. the Eurasian component and African component have large genetic distance (split over 70,000 years ago). So Copts are still closer to Arabs than to Nubians or Horners because they have much less Sub-Saharan.

Maybe I'm wrong, so correct me. But I took the graphs to mean that although Egyptian Copts are almost completely Eurasian in origin (K2 Dark blue), due to dark green in K4 and K5, their Eurasian ancestors aren't the same as Arabs/qataris but the same as the Eurasian ancestors of Horners/Nubians.
 
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World

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Maybe I'm wrong, so correct me. But I took the graphs to mean that although Egyptian Copts are almost completely Eurasian in origin (K2 Dark blue), due to dark green in K4 and K5, their Eurasian ancestors are the same as Arabs/qataris but the same as the Eurasian ancestors of Horners/Nubians.
aren’t the same as Arabs/qataris*
 

Apollo

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This study proves that the Nubians were originally Cushitic, but shifted languages.

Wrong, Mr Kangz.

They are Nubas from Central Sudan who mixed with Egyptians and Arabs.

They do not carry much of the Cushitic component, they are simply mixed race Nubas who only mixed 700-1000 years ago:

http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1006976

''Genetic evidence points to an early admixture event in the Nubians, concurrent with historical contact between North Sudanese and Arab groups. We estimate the admixture in current-day Sudanese Arab populations to about 700 years ago, coinciding with the fall of Dongola in 1315/1316 AD, a wave of admixture that reached the Darfurian/Kordofanian populations some 400–200 years ago. In contrast to the northeastern populations, the current-day Nilotic populations from the south of the region display little or no admixture from Eurasian groups indicating long-term isolation and population continuity in these areas of northeast Africa.''
 
Mr Kangz,

The scientists date their admixture to 1300 AD, before that they resembled Nubas.

Is this Koombeya Science? :lol:

This are the facts

Nubians are the only Nilo-Saharan speaking group that does not cluster with groups of the same linguistic affiliation, but with Sudanese Afro-Asiatic speaking groups (Arabs and Cushitic Beja) and Afro-Asiatic Ethiopians.

Y-chromosome and mitochondrial DNA studies reported Nubians to be more similar to Egyptians and Ethiopians than to other Nilo-Saharan populations.



A random subset of 18 individuals from each population was selected to avoid sample size bias. Columns represent individuals, where the size of each colour segment represents the proportion of ancestry from each cluster. Although k = 3 is the statistically supported model, here we show the results from k = 2 through k = 5 as they explain several ancestral components: North African/Middle Eastern (dark blue), Sub-Saharan (light blue), Coptic/Cushitic (dark green), Nilo-Saharan (light green) and Fulani (pink). MKK = Maasai from Kinyawa, Kenya; LWK = Luhya from Webuye, Kenya; YRI = Yoruba from Ibadan, Nigeria.

Populations from the North-East cluster: Beja, Ethiopians, Arabs and Nubians (Table 2) may be explained as admixture products of an ancestral North African population (similar to Copts).
 
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