Haplogroup K1a1b1a (mtDNA)

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Haplogroup K1a1b1a
Possible time of origin 4,800 ± 3600 Years Ago
Possible place of origin Europe
Ancestor K1a1b1
Descendants None at present
Defining mutations (114) 10978 12954 16234[1]

In human mitochondrial genetics, Haplogroup K1a1b1a is a human mitochondrial DNA (mtDNA) haplogroup.

The K1a1b1a mitochondrial DNA haplogroup subclade is found in Ashkenazi Jews and other populations. It is a subclade under haplogroup U'K.

Origin

According to National Geographic's Genographic Project, K1a1b1a has an unknown origin. The site states, "Though the origin of this lineage is not clear, it is a founding population among some Jewish Diaspora groups. Among Ashkenazi Jews, it is about 19 percent of maternal lineages. Interestingly, it is also present in some Romani populations". Estimates of the age of K1a1b1a vary depending on the mutation rates used. The age of K1a1b1a has been estimated at 4,800 ± 3600 Years Ago, according to the Genographic Project.

The K1a1b1a subclade is under the U'K haplogroup and descends from K1a1b1, which is thought to be an 11,500 year old European subclade of mostly non Jewish origins. Haplogroup K falls under the old U8 grouping. Some of the Basque people of Spain and France fall under the U8a subclade within U8. K1a1b1a is a U8b subclade within U8, with several downstream variations.

Ötzi, a mummy who was found September 1991 in the Ötztal Alps, is subclade K1ö for Ötzi. It is interesting to note that Ötzi has mtDNA marker 10978 in common with the Ashkenazi population and others who fall under the K1a1b1a subclade.

A new study and recent updates to the mtDNA tree uses three markers to define K1a1b1a, (114), 10978 and 16234. The marker 12954 along with the previous three markers mentioned, are used to define a new mtDNA subclade called K1a1b1a1.[2] This new group consists of people who are either Ashkenazi or of non Ashkenazi European ancestry.

Distribution

10% of Europeans fall under the K haplogroup. It is hypothesized that the subclade represents one of four major founding maternal lineages ("founding mothers") of Ashkenazi Jews which together account for 45% of all Ashkenazi mtDNA haplotypes. Approximately 19% of Ashkenazi Jews with ancestry from Poland are in mtDNA haplogroup K1a1b1a.[3] However, K1a1b1a has also been found in individuals of no known Jewish ancestry, and the explanation will require further research. The Genographic Project along with other research groups are looking into this phenomenon. The haplogroup is distributed in Europe and the Middle East.[4] Estimates suggest approximately 1,600,000 Jews worldwide would be K1a1b1a.

The recently evolving field of genetic genealogy and DNA sequencing has permitted people of unknown ancestry to make use of DNA testing to establish some evidence for their ancestral origins. Accordingly, based on the research of Behar,[3] some connection has been established between the K1a1b1a subclade and Jewish ancestry, but that remains unclear in light of newer studies as of 2013,[2] as well as the Romani carrying K1a1b1a.

Version 3 of van Oven's Phylotree[1] defines K1a1b1a by the highly polymorphic 114 in the second hypervariable region, 10978 and 12954 in the coding region, and 16234 in the first hypervariable region. This is supported by a growing number of Genbank samples. However, 12954 is not needed to define K1a1b1a as of 2013 and as mentioned above, is used to define K1a1b1a1. [2]

Genbank Submissions
Genbank ID Origin Ethnicity Author
FJ228404 Falticeni, Romania Ashkenazi Greenspan,B. (FTDNA)
EU926147 USA Jewish Greenspan,B. (FTDNA)
EU523126 U/N U/N Greenspan,B. (FTDNA)
EU327782 Zhitomir, Ukraine Ukrainian Greenspan,B. (FTDNA)
EU259709 U/N U/N Greenspan,B. (FTDNA)
EU170362 U/N U/N Greenspan,B. (FTDNA)
EU052292 U/N U/N Greenspan,B. (FTDNA)
EU862197 USA European Greenspan,B. (FTDNA)
DQ301803 U/N U/N Behar, D.

It may be recognized in hypervariable only samples by essential mutations:

  • Hypervariable region 1: 16224C, 16234T, 16311C, 16519C
  • Hypervariable region 2: 073G, 263G, 315.1C, 497T

Subclades

Tree

This phylogenetic tree of haplogroup K 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. Newer research has further updated the phylogenetic tree of haplogroup K subclades, adding K1a1b1a1 to the group. [2]

  • K1a1b1 11470
    • K1a1b1a (114) 10978 16234
    • K1a1b1a1 (114) 10978 12954 16234
    • K1a1b1b 2483

See also

Evolutionary 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 c van Oven, Mannis; Manfred Kayser (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. 
  2. ^ a b c d Costa, Marta. "A substantial prehistoric European ancestry amongst Ashkenazi maternal lineages". Nature Communications 4, Article number: 2543 doi:10.1038/ncomms3543 Received 11 July 2013 Accepted 04 September 2013 Published 08 October 2013. Retrieved 2015-01-02. 
  3. ^ a b Behar, Doron; Ene Metspalu, Toomas Kivisild, Alessandro Achilli, Yarin Hadid, Shay Tzur, Luisa Pereira, Antonio Amorim, Lluís Quintana-Murci, Kari Majamaa, Corinna Herrnstadt, Neil Howell, Oleg Balanovsky, Ildus Kutuev, Andrey Pshenichnov, David Gurwitz, Batsheva Bonne-Tamir, Antonio Torroni, Richard Villems, and Karl Skorecki (January 11, 2006). "The Matrilineal Ancestry of Ashkenazi Jewry: Portrait of a Recent Founder Event". American Journal of Human Genetics 78 (3): 487–497. doi:10.1086/500307. PMC 1380291. PMID 16404693. Retrieved 2009-05-08. 
  4. ^ Hurst, William. "mtDNA Haplogroup K: K1a1b1a Subclade Haplotypes" (JPG). mtDNA Haplogroup K Project. 

External links