Haplogroup E (Y-DNA)

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Haplogroup E or E-M96
Time of origin	approx. 52,500 years BP^[1]
Place of origin	East Africa or Near East^[2]
Ancestor	DE
Descendants	E1, E2
Defining mutations	M96

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

This clade is divided into two sub-clades: E1 (or E-P147), defined by SNP mutation P147, and E2 (or E-M75), defined by M75.

E1 is in turn divided in important sub-clades as follows:

E1a, (formerly E1), defined by mutations M33 and M132. Two sub-clades are recognized:

E1a1 (or E-M44, formerly E1a)
E1a2 (or E-P110)

E1b, defined by mutation P177. This in turn contains two very significant sub-clades:

E1b1 (formerly E3). E1b1 is further divided into two sub-clades

E1b1a (formerly E3a)
E1b1b (formerly E3b)

E1b2 (formerly E4)

E2 is less commonly found, and has two recognized sub-clades:

E2a M41/P210
E2b M54, M90, M98. This clade contains E2b1 (E-M85), formerly known as E2b2, and its sub-clades.

E1a and E2 are found almost exclusively in Africa, and only E1b1b is observed in significant frequencies in Europe and western Asia in addition to Africa. Most Sub-Saharan Africans belong to subclades of E other than E1b1b, while most non-Africans who belong to haplogroup E belong to its E1b1b subclade.^[3].

Haplogroup E would appear to have arisen in Northeast Africa based on the concentration and variety of E subclades in that area today. But the fact that Haplogroup E is closely linked with Haplogroup D, which is not found in Africa, leaves open the possibility that E first arose in the Near or Middle East and was subsequently carried into Africa by a back migration^[4].

1 Subclades
- 1.1 E1a
- 1.2 E2
- 1.3 E1b1
2 References
3 External links
- 3.1 Projects

[edit] Subclades

Subclades of Haplogroup E include E1a, E2, E1b1a (M2) and E1b1b (M35).

[edit] E1a

E1a (M33) headed for West Africa and today it is mainly present in the region of Mali.

[edit] E2

E2 (M75) is present among sub-Saharan Africans in both West and East Africa.

[edit] E1b1

Main articles: Haplogroup E1b1a (Y-DNA) and Haplogroup E1b1b (Y-DNA)

E1b1, by far the most frequent clade of E, diverged into two main haplogroups: E1b1b (M35) approximately 24-27 000 years ago (Cruciani et al. 2004), followed by E1b1a (M2) some 10 000 years later.

E1b1a is almost exclusively associated with West/Central/Southern Africans. It is the single most common Y haplogroup in sub-Saharan Africa as well as among African Americans and West Indians. Outside of Africa, it is observed in negligibly small frequencies and its spread is generally attributed to the slave trade.

E1b1b, which is at once the most common Y haplogroup among Ethiopians, Somalis, Eritreans and North African Berbers and Arabs, is also the third most frequently observed Y chromosome haplogroup in Europe. E1b1b has three common subclades: M78, M81, and M34.

M78 is found throughout North and Northeast Africa, as well as the Near East and Europe. Its network shows high geographic structuring. The α cluster is particular to Europe, where it is highest in the Balkans. It enjoys frequencies of about 31.6% among Greeks^[5] with a frequency of about 47% in the Peloponnese region of Greece,^[6] about 25% among Albanians at large^[6] with a frequency of 46% among Albanians in Kosovo^[7], and frequencies of about 20% in some South Slavic populations (Serbs, Macedonians, Bulgarians)^[8]. Among Jews both in Europe and the Middle East, E1b1b is the second most common Y haplogroup after J.^[9]. A β and a γ cluster are particular to North and Northeast Africa, respectively. A fourth, δ, cluster is found in all regions albeit at low frequencies. Cruciani suggests that it was the δ cluster that spread M78 throughout North and Northeast Africa, the Near East and later Europe, c. 14 KYA. It was only during later population expansions bearing the α, β and γ clusters (which diverged from the δ cluster) that led to E1b1b's current high frequency.

In Northeast Africa, the subclade M34 appears to be restricted to Ethiopia. However, M34 chromosomes have been found in a large majority of the populations from the Near East. M34 chromosomes from Ethiopia show lower variances than those from the Near East and appear closely related in the M34 network. Thus, it is assumed that M34 chromosomes were introduced into Ethiopia from the Near East.^[10]

M81, the other major subclade of E1b1b, is heavily concentrated in North Africa among both the Berber and Arab populations of that region. M81 is also found, albeit at low frequencies of 1.6-4%, in Iberia. Cruciani attributes its presence in Iberia to a recent migration of M81 carrying peoples from the Maghreb, perhaps coinciding with the Islamic conquest of Spain.

Scholars such as Hammer et al. and Semino et al. have linked the spread of E1b1b into Europe to an ancient migration from East Africa mediated through North African and Middle Eastern farmers during the Neolithic period. However, given the predominance of α cluster of subclade M78 in Europe, Cruciani concluded that it was spread through Europe via peoples indigenous to Southeastern Europe, perhaps in response to the arrival of Neolithic farming by way of cultural contact with the Near East. In turn, it originally arrived into Europe, perhaps, directly from North or Northeast Africa. Thus, its distribution is not simply due to a process of uniform spread of people from a single Near Eastern origin, but rather a series of distinct migrations.

[edit] References

^ *Karafet et al. (2008), Abstract New Binary Polymorphisms Reshape and Increase Resolution of the Human Y-Chromosomal Haplogroup Tree, Genome Research, DOI: 10.1101/gr.7172008
^ Y-DNA Haplogroup E and its Subclades - 2008
^ Fulvio Cruciani et al, Phylogeographic Analysis of Haplogroup E1b1b (E-M215) Y Chromosomes Reveals Multiple Migratory Events Within and Out Of Africa, Am. J. Hum. Genet, p. 74
^ Y-DNA Haplogroup E and its Subclades - 2008
^ J.R. King et al. (2008)
^ ^a ^b Semino et al. (2004), 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
^ Peričic et al. (2005), High-Resolution Phylogenetic Analysis of Southeastern Europe Traces Major Episodes of Paternal Gene Flow Among Slavic Populations
^ Perici
^ Jewish E1b1b (E3b) Project at FTDNA
^ Cruciani, 2004

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.