Haplogroup T – An ancient Near East haplogroup

Haplogroup T originated at least 30,000 years ago, making it one of the oldest haplogroups found in Eurasia, which may explain its vast dispersal around Africa and South Asia. It also makes its place of origin uncertain. T is descended from haplogroup K, the ancestor of most of the Eurasian haplogroups (L, N, O, P, Q, R and T), and whose origins are thought to lie in the Middle ast or in Central Asia.

Haplogroup T-M184 (M193, M272, L206, PAGES129) is found in an insignificant majority of Kurru, Bauris & Lodha in South Asia; and in a significant minority of Rajus and Mahli in South Asia; Somalis, southern Egyptians and Fulbe in north Cameroon; Chian Greeks, Saccensi/Sicilians, Eivissencs / Ibizans and Northeastern Portuguese Jews in Europe and Zoroastrians, Bakhtiaris/Lurs in the Middle East. Its highest density is actually found among the Fulani people of Cameroon (18% of the population).

The maximal worldwide frequency for haplogroup T is observed in East Africa (Eritrea, Ethiopia, Somalia, Kenya, Tanzania). It is common in northern Somalia and in the Somalis of Ethiopia. It is found in frequency of greater than 10 percent in populations of Kenya Tanzania and Cameroon.

Although haplogroup T is more common today in East Africa than anywhere else, it almost certainly spread from the Fertile Crescent with the rise of agriculture. Indeed, the oldest subclades and the greatest diversity of T is found in the Middle East, especially around the Fertile Crescent. The higher frequency of T in East Africa would be due to a founder effect among Neolithic farmers from the Middle East.

In the Middle East, especially the South Caucasus, southern Iraq, south-west Iran, Oman and southern Egypt, it accounts for approximately 5 to 15% of the male lineages. During the Chalcolithic and Bronze Age haplogroup T would have been an important (though probably not dominant) lineage among ancient peoples such as Sumerians and the Elamites.

Haplogroup T is common in northern Somalia and in the Somalis of Ethiopia. It is found in frequency of greater than 10 percent in populations of Kenya Tanzania and Cameroon. It is notable for being widespread in Tanzania where it is more common than Kenya . It has also been detected in the limba populations of Zimbabwe Malawi and South Africa. The distribution of this haplogroup has been suggested to be associated with mtdna haplogroup M1 as the two tend to be common in the same regions.

It is notable for being widespread in Tanzania where it is more common than Kenya. It has also been detected in the limba populations of Zimbabwe Malawi and South Africa. The distribution of this haplogroup has been suggested to be associated with mtdna haplogroup M1 as the two tend to be common in the same regions.

Haplogroup T-M184 is not associated with the R1, G and J lineages that entered Africa from Eurasia relatively recently. Luis et al. (2004) suggest that the presence of the clade on the African continent may, like R1* representatives, point to an older introduction from Asia. The Levant rather than the Arabian Peninsula appears to have been the main route of entry, as the Egyptian and Turkish haplotypes are considerably older in age (13,700 ybp and 9,000 ybp, respectively) than those found in Oman (only 1,600 ybp).

According to the authors, the spotty modern distribution pattern of haplogroup T-M184 within Africa may therefore represent the traces of a more widespread early local presence of the clade. Later expansions of populations carrying the E1b1b, E1b1a, G and J NRY lineages may have overwhelmed the T-M184 clade-bearers in certain localities.

Possible patterns between Y-chromosome and elite endurance runners were studied in an attempt to find a genetic explanation to the Ethiopian endurance running success. Given the superiority of East African athletes in international distance running over the past four decades, it has been speculated that they are genetically advantaged. Elite marathon runners from Ethiopia were analysed for K*(xP) which according to the previously published Ethiopian studies is attributable to the haplogroup T and specifically to the T1a1a* (old T1a*) subclade, according to further studies.

T1a1a* was found to be proportionately more frequent in the elite marathon runners sample than in the control samples than any other haplogroup, therefore this y-chromosome could play a significant role in determining Ethiopian endurance running success.

Haplogroup T1a1a* was found in 14% of the elite marathon runners sample of whom 43% of this sample are from Arsi province. In addition, haplogroup T1a1a* was found in only 4% of the Ethiopian control sample and only 1% of the Arsi province control sample. T1a1a* is positively associated with aspects of endurance running, whereas E1b1b1 (old E3b1) is negatively associated.

Family Tree DNA, a commercial genetic genealogy company, has displayed a map that shows a relatively high frequency of haplogroup T-M184 in some Australian aborigines. Probably the populations coincide with those previously reported in several studies as K*(M9), with a frequency near to 30% in Northern Australia. According to Family Tree DNA, the defining SNP for haplogroup T-M184 is M184, while M70 defines T1.

Finally, the moderately high frequency (∼18%) of T1b* chromosomes in the Lembas, theorized to have a Jewish origin on the basis of its possessing the 6-marker Cohen Modal Haplotype within haplogroup J, of southern Africa supports the hypothesis of a Near Eastern, but not necessarily a Jewish, origin for their paternal line.

The distribution of haplogroup T-M184 in most parts of Europe is patchy or regionalized; for example, haplogroup T-M184 was found in 1.7% (10/591) of a pool of six samples of males from southwestern Russia, but it was completely absent from a pool of eight samples totalling 637 individuals from the northern half of European Russia.

These subclades probably represent one of the Neolithic migration from the Fertile Crescent to Southeast Europe. They would then have spread around central and Eastern Europe, as far north as the eastern Baltic.

Haplogroup T is a fairly rare lineage in Europe. It makes up only 1% of the population on most of the continent, except in Greece, Macedonia and Italy where it exceeds 4%, and in Iberia where it reaches 2.5%, peaking at 10% in Cadiz and over 15% in Ibiza.

The occurrence in Europe of lineages belonging to both T1a1 (old T1a) and T1a2 (old T1b) subclades probably reflects multiple episodes of gene flow. T1a1* haplogroups in Europe likely reflect older gene flow.

While almost all subclades of T are found in the Middle East, most Europeans outside the Mediterranean belong to the subclades T1a2 (L131) and T1a1a1a (P77), who are also found in Anatolia.

T1a2 has been found as far east as the Volga-Ural region of Russia and Xinjiang in north-west China. This branch probably penetrated into the Pontic-Caspian Steppe during the Neolithic (perhaps alongside G2a3b1 and J2b2) and became integrated to the indigenous R1a peoples before their expansion to Central Asia during the Bronze Age.

Autosomal DNA tests have also identified unusually high percentages of Southwest Asian admixtures among the Finns (1 to 2.5%) and Lithuanians (1.5%), who otherwise lack West Asian or Caucasian admixture and possess hardly any Middle Eastern Y-DNA. This Southwest Asian admixture could be the trace of T lineages absorbed during the Neolithic.

Haplogroup T has been found at a relatively high frequency among the Tatars (5%) and Maris (2%) of the Volga-Ural region as well as in north-west Russia (3%) and Estonia (3.5%) suggesting that it may have been one of the principal lineages bringing the Neolithic to Uralic-speaking population.

The modern distribution T in Europe strongly correlates with a the Neolithic colonisation of Mediterranean Europe by Near-Eastern farmers, notably the Cardium Pottery culture (5000-1500 BCE).

The higher than average frequencies of haplogroup T in places like Cyprus, Sicily, Tunisia, Ibiza, Andalusia and the northern tip of Morocco suggest that haplogroup T could have been dispersed around the Mediterranean by the Phoenicians (1200-800 BCE), and that ancient Phoenicia seemingly had a higher incidence of T than Lebanon does today (5%).

Besides these regions and Europe, T is found in isolated pockets as far as Central Asia, India, Cameroon, Zambia and South Africa.

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