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==Known Origins==
==Known Origins==
Mitochondrial (mtDNA) Haplogroup T derives from the [[Haplogroup JT (mtDNA)|haplogroup JT]], which also gave rise to [[Haplogroup J (mtDNA)|haplogroup J]]. Haplogroup T is thought to have originated in [[Mesopotamia]] and/or the [[Fertile Crescent]] (modern [[Syria]] and [[Turkey]]) approximately 10,000-12,000 years ago, and then moved northwest in to Europe and east as far as modern Pakistan and India.
Mitochondrial (mtDNA) Haplogroup T derives from the [[Haplogroup JT (mtDNA)|haplogroup JT]], which also gave rise to [[Haplogroup J (mtDNA)|haplogroup J]]. Haplogroup T is thought to have originated in [[Mesopotamia]] and/or the [[Fertile Crescent]] (modern [[Syria]] and [[Turkey]]) approximately 45,000-50,000 years ago, and then moved northwest in to Europe and east as far as modern Pakistan and India.


In his popular book ''[[The Seven Daughters of Eve]]'', [[Bryan Sykes]], who is himself in Haplogroup T, named the originator of this group "Tara," which means ''rocky hill'' in [[Goidelic languages|Gaelic]]. Sykes believes that: "Tara herself lived 17,000 years ago in the northwest of Italy among the hills of [[Tuscany]] and along the estuary of the [[river Arno]]."<ref name="oxfordancestors.com"/>
In his popular book ''[[The Seven Daughters of Eve]]'', [[Bryan Sykes]], who is himself in Haplogroup T, named the originator of this group "Tara," which means ''rocky hill'' in [[Goidelic languages|Gaelic]]. Sykes believes that: "Tara herself lived 17,000 years ago in the northwest of Italy among the hills of [[Tuscany]] and along the estuary of the [[river Arno]]."<ref name="oxfordancestors.com"/>

Revision as of 05:53, 29 October 2011

Haplogroup T
Possible time of originapprox. 45,000-50,000 years before present
Possible place of originbelieved to be Mesopotamia, the Fertile Crescent, and/or modern Syria and Turkey
AncestorJT
DescendantsT1, T2
Defining mutations709, 1888, 4917, 8697, 10463, 13368, 14905, 15607, 15928, 16294, 16519[1]

In human mitochondrial genetics, Haplogroup T is a human mitochondrial DNA (mtDNA) haplogroup.

Known Origins

Mitochondrial (mtDNA) Haplogroup T derives from the haplogroup JT, which also gave rise to haplogroup J. Haplogroup T is thought to have originated in Mesopotamia and/or the Fertile Crescent (modern Syria and Turkey) approximately 45,000-50,000 years ago, and then moved northwest in to Europe and east as far as modern Pakistan and India.

In his popular book The Seven Daughters of Eve, Bryan Sykes, who is himself in Haplogroup T, named the originator of this group "Tara," which means rocky hill in Gaelic. Sykes believes that: "Tara herself lived 17,000 years ago in the northwest of Italy among the hills of Tuscany and along the estuary of the river Arno."[2]

The International Society of Genetic Genealogy gives the following standardized description about mtDNA Haplogroup T and two of its main subclades:

"The mitochondrial Haplogroup T is best characterized as a European lineage. With an origin in the Near East greater than 45,000 years ago, the major sub-lineages of Haplogroup T entered Europe around the time of the Neolithic 10,000 years ago. Once in Europe, these sub-lineages underwent a dramatic expansion associated with the arrival of agriculture in Europe. Today, we find Haplogroup T*, the root Haplogroup for Haplogroup T, widely distributed in Europe."

About subclade T1 they write: "The origin of Haplogroup T1 dates to at least 6,000 years ago, and today, we find Haplogroup T1 distributed in populations living in southeast, central, and northwestern Europe."

Regarding subclade T2: "Haplogroup T2 is one of the older sub-lineages and may have been present in Europe as early as the Late Upper Palaeolithic."

Current Distribution

Haplogroup T is currently found with high concentrations around the eastern Baltic Sea. According to Oxford Ancestors, Haplogroup T "includes slightly fewer than 10% of modern Europeans. Its many branches are widely distributed throughout southern and western Europe with particularly high concentrations in Ireland and the west of Britain."[2] According to the Genographic Project: "Haplogroup T has a very wide distribution, and is present as far east as the Indus Valley bordering India and Pakistan and as far south as the Arabian peninsula. It is also common in eastern and northern Europe." [3]

Early agriculturalists and pastoralists

The Genographic Project states that early people with Haplogroup T were likely some of the first organized agriculturalists and pastoralists, and that they probably comprised the group which first brought settled agriculture and pastoralism on to the European continent, bringing the "Neolithic Revolution" to Europe; they write: "Although the haplogroup was present during the early and middle Upper Paleolithic, [Haplogroup] T is generally considered one of the main genetic signatures of the Neolithic expansions. While groups of hunter-gatherers and subsistence fishermen had been occupying much of Eurasia for tens of thousands of years, around ten thousand years ago a group of modern humans living in the Fertile Crescent-present day eastern Turkey and northern Syria-began domesticating the plants, nuts, and seeds they had been collecting. What resulted were the world's first agriculturalists, and this new cultural era is typically referred to as the Neolithic. Groups of individuals able to support larger populations with this reliable food source began migrating out of the Middle East, bringing their new technology with them. By then, humans had already settled much of the surrounding areas, but this new agricultural technology proved too successful to ignore, and the surrounding groups quickly copied these new immigrants. Interesting, DNA data indicate that while these new agriculturalists were incredibly successful at planting their technology in the surrounding groups, they were far less successful at planting their own genetic seed. Agriculture was quickly and widely adopted, but the lineages carried by these Neolithic expansions are found at frequencies seldom greater than 20 percent in Europe, the Middle East, and Central Asia." [3]

Health Issues

Some studies have shown Haplogroup T to be associated with increased risk for coronary artery disease.[4] However, some studies have also shown that people of Haplogroup T are less prone to diabetes.[5]

A few tentative medical studies have demonstrated that Haplogroup T may offer some resistance to both Parkinson's disease and Alzheimer's disease.[6]

Certain medical studies had shown mitochondrial Haplogroup T to be associated with reduced sperm motility in males, although these results have been challenged.[7] According to the Departamento de Bioquimica y Biologica Molecular y Celular, Universidad de Zaragoza, Haplogroup T represents a weak genetic background that can predispose to asthenozoospermia.[8] However, these findings have been disputed.

People of mtDNA Haplogroup T

The last Russian Tsar, Nicholas II, has been shown to be of Haplogroup T, specifically subclade T2.[9] This was established when genetic testing was done on his remains to authenticate his identity. Assuming all relevant pedigrees are correct, this includes all female-line descendants of his female line ancestor Barbara of Celje (1390-1451), wife of Sigismund, Holy Roman Emperor. This includes a great number of European nobles, including George I of Great Britain and Frederick William I of Prussia (through the Electress Sophia of Hanover), Charles I of England, George III of the United Kingdom, George V of the United Kingdom, Charles X Gustav of Sweden, Gustavus Adolphus of Sweden, Maurice of Nassau, Prince of Orange, Olav V of Norway, and George I of Greece. Many European royals have been found to be of this mtDNA Haplogroup, in addition to Haplogroup H (mtDNA).

The American outlaw Jesse James has been shown to be of subclade T2.

Subclades

Tree

This phylogenetic tree of Haplogroup T subclades is based on the paper by Mannis van Oven and Manfred Kayser Updated comprehensive phylogenetic tree of global human mitochondrial DNA variation[1] and subsequent published research.

  • T
    • T1
      • T1a
      • T1b
    • T2
      • T2a
        • T2a1
          • T2a1a
            • T2a1a1
          • T2a1b
      • T2b
        • T2b1
        • T2b2
        • T2b3
          • T2b3a
        • T2b4
        • T2b5
        • T2b6
      • T2c
        • T2c1
          • T2c1a
          • T2c1b
      • T2d
      • T2e
          • T2e1
        • T2e2
      • T2f
        • T2f1
      • T2g

See also

Phylogenetic tree of human mitochondrial DNA (mtDNA) haplogroups

  Mitochondrial Eve (L)    
L0 L1–6  
L1 L2   L3     L4 L5 L6
M N  
CZ D E G Q   O A S R   I W X Y
C Z B F R0   pre-JT   P   U
HV JT K
H V J T

References

  1. ^ a b van Oven, Mannis (13 Oct 2008). "Updated comprehensive phylogenetic tree of global human mitochondrial DNA variation". Human Mutation. 30 (2): E386–E394. doi:10.1002/humu.20921. PMID 18853457. Retrieved 2009-05-20. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  2. ^ a b Maternal Ancestry, Oxford Ancestors Ltd
  3. ^ a b Atlas of the Human Journey, The Genographic Project
  4. ^ 30 Mitochondrial haplogroup T is associated with coronary artery disease, Mitochondrion, Volume 7, Issue 6, December 2007, Page 412
  5. ^ Mitochondrial DNA haplotype ‘T’ carriers are less prone to diabetes, September 6, 2008, Mathilda’s Anthropology Blog
  6. ^ Phylogenetic Networks for the Human mtDNA Haplogroup T, David A. Pike, "Elsewhere it has been reported that membership in haplogroup T may offer some protection against Alzheimer Disease (Chagnon et al. 1999; Herrnstadt et al. 2002) and also Parkinson's Disease (Pyle et al. 2005), but the cautionary words of Pereira et al. suggest that further studies may be necessary before reaching firm conclusions."
  7. ^ Natural selection shaped regional mtDNA variation in humans
  8. ^ Ruiz-Pesini E, Lapeña AC, Díez-Sánchez C; et al. (2000). "Human mtDNA haplogroups associated with high or reduced spermatozoa motility". Am. J. Hum. Genet. 67 (3): 682–96. doi:10.1086/303040. PMC 1287528. PMID 10936107. {{cite journal}}: Explicit use of et al. in: |author= (help); Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
  9. ^ ISOGG's Famous DNA

External links

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