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Y-chromosome analysis in Egypt suggests a genetic regional continuity in northeastern Africa Human Biology, Oct 2002 by Manni, Franz, Leonardi, Pascal, Barakat, Abdelhamid, Rouba, Hassan, Et al Abstract The geographic location of Egypt, at the interface between North Africa, the Middle East, and southern Europe, prompted us to investigate the genetic diversity of this population and its relationship with neighboring populations. To assess the extent to which the modern Egyptian population reflects this intermediate geographic position, ten Unique Event Polymorphisms (UEPs), mapping to the nonrecombining portion of the Y chromosome, have been typed in 164 Y chromosomes from three North African populations. The analysis of these binary markers, which define 11 Y-chromosome lineages, were used to determine the haplogroup frequencies in Egyptians, Moroccan Arabs, and Moroccan Berbers and thereby define the Y-chromosome background in these regions. Pairwise comparisons with a set of 15 different populations from neighboring European, North African, and Middle Eastern populations and geographic analysis showed the absence of any significant genetic barrier in the eastern part of the Mediterranean area, suggesting that genetic variation and gene flow in this area follow the "isolation-by-distance" model. These results are in sharp contrast with the observation of a strong north-south genetic barrier in the western Mediterranean basin, defined by the Gibraltar Strait. Thus, the Y-chromosome gene pool in the modern Egyptian population reflects a mixture of European, Middle Eastern, and African characteristics, highlighting the importance of ancient and recent migration waves, followed by gene flow, in the region.
The northern part of Africa is separated from the rest of the continent by the Sahara Desert, which continues almost uninterrupted from the Atlantic Ocean to the Red Sea. As a consequence of this important geographic boundary, human movements may have been limited to the Nile Valley and Red Sea to the east, and to the Atlantic coast on the west. These two areas represent potential pivotal regions that may shed light on different migration waves during human history, including those related to the "out-of-Africa" hypothesis on the origin of modern humans and also to populations movements towards Africa, such as Neolithic diffusion of agriculturalists from the Middle East.
Despite the importance associated with the northeastern part of Africa in human history, few studies have defined the genetic background prevailing in modern populations in this key geographic region. When this genetic data is used to determine the genetic affinity of the Egyptian population in a wider regional context, the results are controversial. On the basis of classical genetic polymorphisms, Egypt, together with Libya, is more closely related to European populations than other African populations (Bosch et al. 1997), whereas autosomal short tandem repeat loci (STRs) suggest important genetic differences between the Egyptian and European populations (Klintschar et al. 1999). Both of these studies do show considerable intrapopulation variability. In addition, there is evidence of gene flow from sub-Saharan Africa to North Africa. Mitochondrial DNA (mtDNA) studies in different populations inhabiting the Nile Valley have suggested that this region acted as a corridor for gene flow between sub-Saharan and North Africa (Krings et al. 1999), an observation also suggested by mitochondrial DNA analysis in remains of ancient Nubians (Fox 1997). Indeed, the development of early civilizations along the valley may have increased gene flow along the Nile.
Africa has three contact zones with neighboring continents: the Sinai Desert in the northeast, the Gibraltar Strait in the northwest, and the Bab-el-Mandeb Strait, which separates Ethiopia from the Arabian Peninsula. In the last few years, several studies have attempted to reveal migration routes from Africa both to Europe and to Asia, as well as to identify areas of gene flow between these continents. In this context, populations on either side of the Gibraltar Strait (which separates northwest [NW] Africa from the Iberian Peninsula by only 15 km and is a possible contact zone between African and southern European populations) exhibit strong genetic differences (Bosch et al. 2000a; 2000b, 2001; Comas et al. 2000). Even if a certain degree of gene flow into Southern Iberia may have existed (Flores et al. 2000; 2001), the Gibraltar Strait appears to have represented a strong barrier to genetic exchange between the two continents. In contrast, mtDNA studies indicate considerable gene flow through the Bab-el-Mandeb Strait in East Africa, leading to the proposal of an early exit of modern humans from Africa via East Africa and the Arabian Peninsula (Quintana-Murci et al. 1999). The third contact zone, the Sinai Desert and Sinai Peninsula, is potentially an important migratory route, both terrestrial and coastal, enabling contacts with the Middle East, Europe, and Asia. However, to date there have been no studies to evaluate how this contact zone has or has not influenced gene flow.
Posts: 315 | From: Deep Earth | Registered: Feb 2007
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Why would Ancient Egypt be different from its modern counterpart? Humans have been travelling and migrating since the dawn of human existence on earth. The land of Egypt seems to have been the Melting Pot of the Ancient World.
Posts: 315 | From: Deep Earth | Registered: Feb 2007
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quote:Originally posted by Glider: Why would Ancient Egypt be different from its modern counterpart? Humans have been travelling and migrating since the dawn of human existence on earth. The land of Egypt seems to have been the Melting Pot of the Ancient World.
*Sigh*, this has been discussed tirelessly on this board. To single out Egypt as the world's first and most notable "melting pot" is intellectually dishonest and deceptively simplistic to say the least, especially if this sort of emphasis isn't applied to Greece, Israel, or any other region adjacent to the African continent. The point basically is that the processes which gave rise to the civilizations of the Nile Valley were indigenous in origin. As far as diffusionist models indicating migration into the said region by Afrasian-speaking agriculturalists from the Middle East, this isn't viable given the clear fact that most linguists place the origins of the Afro-Asiatic language phylum further south in Southwest Ethiopia or the eastern desert and food production developed locally as an independent advancement in the Sahara(and not regions bordering the Middle East).
the first signs of both livestock raising and grain cultivation in Africa appear in what is now the middle of the Sahara desert. - Dr. Susan J. Herlin
Here is a more up-to-date assessment on Y-chromosome variation in Egypt..
quote:History in the interpretation of the pattern of p49a,f TaqI RFLP Y-chromosome variation in Egypt: a consideration of multiple lines of evidence
The possible factors involved in the generation of p49a,f TaqI Y-chromosome spatial diversity in Egypt were explored. The object was to consider explanations beyond those that emphasize gene flow mediated via military campaigns within the Nile corridor during the dynastic period. Current patterns of the most common variants (V, XI, and IV) have been suggested to be primarily related to Middle Kingdom and New Kingdom political actions in Nubia, including occasional settler colonization, and the conquest of Egypt by Kush (in upper Nubia, northern Sudan), thus initiating the Twenty-Fifth Dynasty. However, a synthesis of evidence from archaeology, historical linguistics, texts, distribution of haplotypes outside Egypt, and some demographic considerations lends greater support to the establishment, before the Middle Kingdom, of the observed distributions of the most prevalent haplotypes V, XI, and IV. It is suggested that the pattern of diversity for these variants in the Egyptian Nile Valley was largely the product of population events that occurred in the late Pleistocene to mid-Holocene through the First Dynasty, and was sustained by continuous smaller-scale bidirectional migrations/interactions. The higher frequency of V in Ethiopia than in Nubia or upper (southern) Egypt has to be taken into account in any discussion of variation in the Nile Valley.
As far as Mitochondrial DNA assessment, this should be of relevant interest also..
quote: The mitochondrial DNA (mtDNA) diversity of 58 individuals from Upper Egypt, more than half (34 individuals) from Gurna, whose population has an ancient cultural history, were studied by sequencing the control-region and screening diagnostic RFLP markers. This sedentary population presented similarities to the Ethiopian population by the L1 and L2 macrohaplogroup frequency (20.6%), by the West Eurasian component (defined by haplogroups H to K and T to X) and particularly by a high frequency (17.6%) of haplogroup M1. We statistically and phylogenetically analysed and compared the Gurna population with other Egyptian, Near East and sub-Saharan Africa populations; AMOVA and Minimum Spanning Network analysis showed that the Gurna population was not isolated from neighbouring populations. Our results suggest that the Gurna population has conserved the trace of an ancestral genetic structure from an ancestral East African population, characterized by a high M1 haplogroup frequency. The current structure of the Egyptian population may be the result of further influence of neighbouring populations on this ancestral population.
In response to your question, "Why would Ancient Egypt be different from its modern counterpart", because the historical records indicate substantial immigration from the Near east and Europe during Egypt's demise and subsequent colonization, with other reports of in migration even during the middle Kingdom in the form of the Hyksos invasions. Prof. Keita tells us that "an average migration rate of one percent per generation into a region could result in a great change of the original gene frequencies in only several thousand years." Hope that answers your question.. Posts: 4021 | From: Bay Area, CA | Registered: Mar 2007
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quote:Originally posted by Glider: Why would Ancient Egypt be different from its modern counterpart
^ Because it has been conquered by wave after wave of Persian, Syrian, Romon, Greek and Arab.
The study you site doesn't refute this. It speaks of continuity and change. You somehow interpret the above as stasis, which is incorrect.
Sundiata quotes: "Prof. Keita tells us that "an average migration rate of one percent per generation into a region could result in a great change of the original gene frequencies in only several thousand years."
^ That is also continuity.....of change.
Posts: 15202 | Registered: Jun 2004
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^ The study above explains the presence of African Y-chromosomal lineages in the Levant that date from the Mesolithic. And that some of these lineages are found in Europe, especially Greece.
Posts: 26260 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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