Haplogroup E (Y-DNA)

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In human genetics, Haplogroup E (M96) is a human Y-chromosome DNA haplogroup.

This haplogroup is found in Africa, the Middle East, and Europe. Haplogroup E is found in Africa, Asia and Europe and it is divided into three clades: E1 and E2 are found exclusively in Africa, while E3 is observed in Africa, Europe and western Asia. E3 is further divided into E3a and E3b, but only E3b is observed in significant frequency in Europe and western Asia in addition to Africa. E3b is estimated to be 25 600 years old. <ref>Fulvio Cruciani et al, Phylogeographic Analysis of Haplogroup E3b (E-M215) Y Chromosomes Reveals Multiple Migratory Events Within and Out Of Africa, Am. J. Hum. Genet., p. 74</ref> Most Sub-Saharan Africans belong to E(xE3b), while most non-Africans belong to the E3b clade of the E haplogroup.”

1 Subgroups
- 1.1 E1
- 1.2 E2
- 1.3 E3
2 References
3 External links

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Subgroups

Subbranches include E1, E2, E3a (M2) and E3b (M35).

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E1

E1 (M33) headed for West Africa and today it is mainly present in the region of Mali.

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E2

E2 (M75) is present both in West and East Africa.

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E3

Main article: Haplogroup E3a (Y-DNA)

E3, by far the most frequent subbranch of E, diverged into two main subbranches E3a (M2) and E3b (M35) approximately 24-27 000 years ago (Cruciani et al. 2004). E3* itself appears to be most prevalent in east Africa, particularly Ethiopia (Semino et al., 2004)

Both E3a and E3b are found outside of their African homeland, but E3b is relatively more frequent in Europe and western Asia than its sister clade E3a, thanks to gene flow from North Africa and to a lesser degree, from the African Horn in sub-Saharan East Africa [to the other side of the Red Sea], where E3b bearing chromosomes appear to be the most prevalent. The most commonly distributed E3b sub-branch is E-M78. The flow of E3b can be summerized into about four main episodes, based on geographic and quantitative analysis of haplogroup and micro satellite diversity:

1) Sometime in the Upper Paleolithic, between 23.9 and 17.3ky ago, E3b (M215) bearing chromosomes were introduced to northeast Africa from sub-Saharan East Africa.

2) The M78 mutation (E3b1) then occurred in the E3b chromosomes distributed in Northeast Africa, to be followed by a back-migration episode to sub-Saharan East Africa, sometime between 18ky and 5.9ky ago. Some chromosomes which had acquired the M78 mutation in Northeast Africa undoubtedly also made their way westward in North Africa.

3) Sometime around 13ky ago,these M78 bearing E3b chromosomes were introduced to Europe directly from northern Africa.

4) Between 20 and 6.8ky ago, M78 bearing E3b chromosomes were introduced into western Asia from Northeast Africa. Crucian et al. 2007

The bearers of E3a populated the coastal region of West Africa, where they largely mixed with indigenous Pygmy populations and gave birth to modern West Africans speaking languages of the Niger-Congo family. As a result of the historical migrations of the agricultural Bantu-speaking cultures that started ca. 3000 BC, E3a is the most frequent Y-haplogroup in Sub-Saharan Africa today. It is also the most common Y-haplogroup among African American men.

Within eastern Africa, the haplogroup E3b3 (E-M34) appears to be restricted to Ethiopia but E-M34 chromosomes have been found in a large majority of the populations from the Near East. E-M34 chromosomes from Ethiopia show lower variances than those from the Near East and appear closely related in the E-M34 network. Thus, it is assumed that E-M34 chromosomes were introduced into Ethiopia from the Near East.<ref>Cruciani, 2004</ref> In any case, these E-M34 chromosomes are indications of ancient migrations from East Africa.

In populations of Europe, particularly among those that reside near the Mediterranean, Haplogroup E3b is believed to represent ancient genetic influences from both northern Africa and Near East, with the latter having been mediated by West Asian populations entering Europe during the Neolithic revolution (the spread of agriculture from Asia Minor).<ref>Cruciani, 2004</ref> The subbranch E3b1 is present at high frequencies among the Greeks, Albanians, Serbs and South Italians (up to 25%), but its percentage gradually falls below 10% in the Carpathian basin and Iberia, and is negligible in other parts of Europe. Some E3b is instead explained by more recent genetic influence from North Africa, and this includes chromosomes which had acquired the E-M81 mutation.

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References

B. Arredi et al.: A Predominantly Neolithic Origin for Y-Chromosomal DNA Variation in North Africa. American Journal Of Human Genetics, 2004, p. 338–345
F. Cruciani et al.: A Back Migration from Asia to Sub-Saharan Africa Is Supported by High-Resolution Analysis of Human Y-Chromosome Haplotypes. American Journal Of Human Genetics, 2002, p. 1197–1214
F. Cruciani et al.: Phylogeographic Analysis of Haplogroup E3b (E-M215) Y Chromosomes Reveals Multiple Migratory Events Within and Out Of Africa. American Journal Of Human Genetics, 2004, p. 1014–1022
F. Cruciani et al.: Molecular Dissection of the Y Chromosome Haplogroup M-78
J. R. Luis et al.: The Levant versus the Horn of Africa: Evidence for Bidirectional Corridors of Human Migrations. American Journal Of Human Genetics, 2004, p. 523-544
J. J. Sanchez et al.: High frequencies of Y chromosome lineages characterized by E3b1, DYS19-11, DYS392-12 in Somali males. European Journal of Human Genetics, 2005, p. 856–86
A. Salas et al.: The Making of the African mtDNA Landscape. American Journal Of Human Genetics, 2002, p. 1082–1111
O. Semino et al.: Origin, Diffusion, and Differentiation of Y-Chromosome Haplogroups E and J: Inferences on the Neolithization of Europe and Later Migratory Events in the Mediterranean Area. American Journal of Human Genetics, 2004, p. 1023-1034
E. T. Wood et al.: Contrasting patterns of Y chromosome and mtDNA variation in Africa: evidence for sex-biased demographic processes. European Journal of Human Genetics, 2005, p. 867–876
F. Cruciani et al.: Tracing Past Human Male Movements in Northern/Eastern Africa and Western Eurasia: New Clues from Y-chromosomal Haplogroups E-M78 and J-M12, 2007.