Haplogroup N (Y-DNA)

Infobox haplogroup
name =N


origin-date =15,000 to 20,000 years BP
origin-place =
ancestor =NO
descendants =
mutations =M231
members =

In human genetics, Haplogroup N (M231) is a Y-chromosome DNA haplogroup. [ [http://www.isogg.org/tree/ISOGG_HapgrpN07.html ISOGG "Y-DNA Haplogroup N and its Subclades - 2007"] ]

The b2/b3 deletion in the AZFc region of the human Y-chromosome is a characteristic of Haplogroup N haplotypes. This deletion, however, appears to have occurred independently on four different occasions. Therefore this deletion should not be thought as a unique event polymorphism contributing to the definition of this branch of the Y-chromosome tree. [http://www.isogg.org/tree/ISOGG_HapgrpN07.html]

Haplogroup N is the ancestral group for Haplogroup N1 (LLY22g) and its subclades, N1a, N1b, and N1c (formerly known as N1, N2, and N3, respectively). [http://www.isogg.org/tree/ISOGG_HapgrpN08.html] Y-chromosomes that display the M231 and LLY22g mutations that define Haplogroup N and Haplogroup N1 but do not display any of the downstream mutations that define the subclades N1a (M128), N1b (P43), and N1c (TAT) are said to belong to Haplogroup N1*. Y-chromosomes that display the M231 mutation that defines Haplogroup N but do not display the LLY22g mutation that defines Haplogroup N1 are said to belong to Haplogroup N*.

Origins

Haplogroup N is a descendant haplogroup of Haplogroup NO, and is believed to have first appeared in Southeast Asia approximately 15,000 to 20,000 years ago, during the Ice Age. It is believed to have been transported across Eurasia by small groups of males who, according to some theories, were speakers of Uralic languages. The age estimates of the Uralic language family range from 7000 to 4000 years before present so the Uralic hypothesis of dispersal of Haplogroup N might only be applicable to a time long after the haplogroup's origin, when more precisely defined subclades, especially N1c and N1b, had already formed.

The spread of haplogroup N reveals traces of bottlenecks and founder effects. Haplogroup N did not spread through continuous population growth, but rather through several founding effects. Some Siberian populations have only a few surviving Y-DNA lineages as a mark of massive bottleneck effect. [http://www.springerlink.com/content/yjext4pvt27v7h9f/]

Haplogroup N has a wide geographic distribution throughout Eurasia, from Norway to China.

After Haplogroup N arose in Southeast Asia, males carrying the marker moved to the region of North China and thence to the Altai region (South Siberia). The mutations that define the subclade N1c (old name N3) occurred either in Siberia or in Northwest China. The age of Haplogroup N1c is approximately 14,000 years.

Haplogroup N1b is a significantly younger subclade, perhaps only 6,000 to 8,000 years old. Its first appearance is either in Eastern Europe or in Siberia; the question of its exact origin is still not solved.

The subclade N1c1* likely arose in Southern Siberia during the late Pleistocene (~10,000 years ago), whence it spread to Europe about 8,000 to 10,000 years ago. It is notable that N1c1* has higher frequencyin Eastern Europe than in Siberia. Traditionally, this has been seen as an indicator of an older presence and, thus, the place of origin of a haplogroup. Median-joining trees indicate that N1c1* would have first appeared in South Siberia. However, the possibility of back-migration from Europe cannot be ruled out.

The presence of N1c and N1b in modern Siberian and Asian populations is considered to reflect an ancient substratum, possibly speaking Uralic/Finno-Ugric languages. [http://www.springerlink.com/content/d73858t027m230k3/] , [http://www.nature.com/ejhg/journal/v15/n2/abs/5201748a.html] , [http://www.unboundmedicine.com/medline/ebm/record/17633562/full_citation/%5BGene_pool_differences_between_northern_and_southern_Altaians_inferred_from_the_data_on_Y_chromosomal_haplogroups%5D] , [http://www.blackwell-synergy.com/doi/abs/10.1111/j.1469-1809.2007.00429.x?cookieSet=1&journalCode=ahg] .

Subgroups

The subclades of Haplogroup N with their defining mutation, according to the 2008 YCC tree [http://www.genome.org/cgi/data/gr.7172008/DC1/1] :

*N (M231)
**N*
**N1 (LLY22g)
***N1* "Found in a significant minority of Sino-Tibetan people; also found at low frequency among Altayans, Japanese, Koreans, Manchu, Manchurian Evenks, Sibe, Uyghurs, and Vietnamese"
***N1a (M128) "Found at low frequency among Manchu, Sibe, Manchurian Evenks, Koreans, northern Han Chinese, Buyei, and some Turkic peoples of Central Asia"
***N1b (P43) "Typical of Northern Samoyedic peoples; also found at low to moderate frequency among some other Uralic peoples, Turkic peoples, Mongolic peoples, Tungusic peoples, and Siberian Eskimos"
****N1b*
****N1b1 (P63)
***N1c (Tat (M46), P105) "Typical of the Sakha and Uralic peoples, with a moderate distribution throughout Northern Eurasia"
****N1c*
****N1c1 (M178)
*****N1c1*
*****N1c1a (P21)
*****N1c1b (P67)
*****N1c1c (P119)

References

External links

* [https://www3.nationalgeographic.com/genographic/atlas.html?card=my041 Spread of Haplogroup N] , from The Genographic Project, "National Geographic"
* [http://www.familytreedna.com/public/N%20Y%2DDNA%20Project/ N Y-DNA Haplogroup Project at FamilyTreeDNA]
* [http://www.familytreedna.com/pdf/Derenko2007.pdf Y-chromosome haplogroup N dispersals from south Siberia to Europe]