1Istituto di Medicina Legale, Università Cattolica del Sacro Cuore di Roma, Rome; 2Department of Biochemistry, University of Oxford, Oxford, United Kingdom; 3Department of Anthropology, University of Geneva, Geneva; 4Institut Pasteur de Tunis, Tunis, Tunisia; 5Laboratoire Central, Chu Bab El Oued, Alger, Algeria; 6Department of Cell Biology, University of Calabria, Rende, Italy; and 7The Wellcome Trust Sanger Institute, Hinxton, United Kingdom
Received March 19, 2004; accepted for publication June 7, 2004; electronically published June 16, 2004.
We have typed 275 men from five populations in Algeria, Tunisia, and Egypt with a set of 119 binary markers and 15 microsatellites from the Y chromosome, and we have analyzed the results together with published data from Moroccan populations. North African Y-chromosomal diversity is geographically structured and fits the pattern expected under an isolation-by-distance model. Autocorrelation analyses reveal an east-west cline of genetic variation that extends into the Middle East and is compatible with a hypothesis of demic expansion. This expansion must have involved relatively small numbers of Y chromosomes to account for the reduction in gene diversity towards the West that accompanied the frequency increase of Y haplogroup E3b2, but gene flow must have been maintained to explain the observed pattern of isolation-by-distance. Since the estimates of the times to the most recent common ancestor (TMRCAs) of the most common haplogroups are quite recent, we suggest that the North African pattern of Y-chromosomal variation is largely of Neolithic origin. Thus, we propose that the Neolithic transition in this part of the world was accompanied by demic diffusion of Afro-Asiatic speaking pastoralists from the Middle East.

The interesting thing about this paper, outside of the fact that the sample groups studied are very small is that they basically charecterize the NE Africa as the "Middle East" :

"Under the hypothesis of a neolithic demic expansion from the Middle East, the LIKELY ORIGIN of E3b in East Africa could indicate either a local contribution to the North African Neolithic transition (Barker 2003) or an earlier migration into the Fertile Crescent, preceding the expansion back into Africa."

Is the abstract saying the marker originated int he Middle East and then spread or these pastorialist were Eastern Africans who spread it to the Middle east who then spread it around northern Africa. Help clerify the statements please.

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Originally posted by ausar:
You are going to have to break this down in laymen terms so regular people can understand it . Is the abstract saying the marker originated int he Middle East and then spread or these pastorialist were Eastern Africans who spread it to the Middle east who then spread it around northern Africa. Help clerify the statements please.

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Thought Writes:

This paper seems to state that the North African neolithic contained TWO primary genetic markers - E3b (which originated in east Africa) and J ("Middle east") lineages. They are not certain if these lineages arose by East Africans migrating to the Middle East (mesolithic era) or by Middle Eastern populations migrating to North Africa and mixing with populations with the east African marker E3b. I am of the opinion that both choices are correct:

Here is the abstract on the Haplogroup E3b, originally posted by Said Mohammed:

Y-Chromosome analysis of the Somali population
suggests the origin of the haplogroup E3b1
Juan J. SANCHEZ °
& Claus BØRSTING (°), Charlotte HALLENBERG (°); Alexis HERNANDEZ (*) ; Niels MORLING (°)
(°) Department of Forensic Genetics, Institute of Forensic Medicine, University of Copenhagen, 11 Frederik V’s Vej, DK-2100, Denmark. juan.sanchez@forensic.ku.dk
(*) Instituto Nacional de Toxicología, Departamento de Canarias, La Laguna, Tenerife, Spain.
We genotyped a total of 389 males from Somalia, Sub-Saharan Western Africa, Turkey, and Iraq by a PCR based assay with co-amplification of 25 DNA-fragments and detection of 35 Y chromosome biallelic markers with the single base primer extension technique. A total of 19 different haplogroups were identified. In Somalis, 14 haplogroups were identified. The haplogroup E3b1*(xE3b1b) was found in 77.2 % of the male Somali population, in 6.3 % of Iraqi males and in 1.7 % of male Turks whereas E3b1* was not found in Sub-Saharan Western African males. The frequency of haplogroup E3b1*(xE3b1b) in Somali males is the highest observed in any populations to date, and we suggest that the Somali male population is the origin of this haplogroup. Furthermore, the results are in agreement with a gene flow from Eastern to Northern Africa from a homeland in Somalia. In Somalis, 13.4 % of the males carried J or K haplogroups, which are found relatively frequent in e.g. Iraqis, Turks, and other Arab and Asian populations. This might reflects the historical findings of foreign trading posts at the Somali Gulf of Aden from the 7th century. The distribution of haplogroups will be compared to those in Western African population.

Thought Writes:

Here is another new abstract on this quintesential East African signature gene:

http://hgm2004.hgu.mrc.ac.uk/Abstracts/Publish/WorkshopPosters/WorkshopPosters15/hgm367.html

HGM2004 Poster Abstracts
15. Genome Diversity and Genome Dynamics

Poster 367
Human Y-chromosome haplogroup E3b in Africa: a phylogeographic study
1Fulvio Cruciani, 1Roberta La Fratta, 1Piero Santolamazza, 2Daniele Sellitto, 3Roberto Pascone, 3Salvatora Arachi, 4Pedro Moral, 5Elizabeth Watson, 6Eliane Beraud Colomb, 1,2Rosaria Scozzari
1Dipartimento di Genetica e Biologia Molecolare, Università di Roma, Rome, Italy, 2Istituto di Biologia e Patologia Molecolare del Consiglio Nazionale delle Ricerche, Rome, Italy, 3Dipartimento di Scienze Ginecologiche Perinatologia e Puericultura, Rome, Italy, 4Departament de Biologia Animal, Universitat de Barcelona, Barcelona, Spain, 5The Swedish Museum of Natural History, Stockholm, Sweden, 6Laboratoire d'Immunologie, Hôpital de Sainte-Marguerite, Marseille, France
We explored the phylogeography of human Y chromosomal haplogroup E3b by analyzing 677 individuals from different African regions. An estimate of 25.6 ky (95% CI: 24.3-27.4 ky) for the TMRCA was obtained for the haplogroup E3b, which most likely originated in Eastern Africa. Our data refine the phylogeny of the entire haplogroup, which appears as a collection of lineages with very different evolutionary histories. The distribution of E-M81 chromosomes in Africa closely matches the present area of distribution of Berber-speaking populations in the continent, suggesting a close haplogroup-ethnic group parallelism. E-M34 chromosomes were more likely introduced in Ethiopia from the Near East. Haplogroup E-M78 was observed over a wide area, including eastern (21.5%) and northern (18.5%) Africa. A microsatellite-based network of the E-M78 chromosomes revealed a strong geographic structuring, with two well differentiated sub-clusters, one of which being present exclusively in eastern Africa and the other in northern Africa. A new biallelic marker (V6) was discovered in the present survey in the TBL1Y gene by DHPLC analysis. This marker identifies a subset of chromosomes (haplogroup E-V6) previously assigned to E-M35*. The haplogroup E-V6 was only observed in Eastern Africa (8.9% in Ethiopia, with a single occurrence both in Somalia and Kenya), further testifying to the richness of E3b lineages in this region.