Haplogroup K2a (Y-DNA)

Haplogroup K2a
Possible time of origin	approximately 47,000 years  BP. [1] [2] [3] (Based on the immediate ancestor K2 originating 47,000–55,000 BP, [4] and the secondary descendant NO approximately 38,000 to 47,000 BP.)
Possible place of origin	Central Asia [5] or Southeast Asia [4]
Ancestor	K2 (M526)
Descendants	Sole primary subclade: K-M2313 (M2313); [3] Confirmed secondary subclades: NO1 (a.k.a. NO-M214) K-Y28394 (a.k.a. NO2) [3] K-FTC181 K-MF106925
Defining mutations	M2308, Z4842 [6]

Hypothetical migration routes of haplogroup K and its subclades.

Haplogroup K2a (M2308, Z4842) is a human Y-chromosome DNA haplogroup. K2a is a primary subclade of haplogroup K2 (M526), which in turn is a primary descendant of haplogroup K (M9). Its sole primary descendant is haplogroup K-M2313 (M2313, Z4858 S11799). ^{[3] [7]}

As of 2025, K-M2313 is known to have at least four primary subclades: Haplogroup NO1 (a.k.a. NO-M214), which has numerous members and the extremely rare subclades: K-Y28394, ^[3] sometimes known as NO2, and K-FTC181,K-MF106925.

Basal, undivergent K2a* (K-M2308*) has been found only in the remains of two Upper Paleolithic individuals, known as "Ust'-Ishim man and "Oase-1", ^[3] who lived in Siberia and the Banat region of south-central Europe, respectively, about 37–45 ky BP.

The current existing branches of K-M2313 are all downstream of K-F549,It diversified into subclades like NO-M214 include a majority of living males in East Asia, Northern Eurasia and South East Asia. Those rare subclades that do not belong to NO-M214 such as K-Y28299 has been found in individuals from India ^[8] and Pakistan, K-F14963 has been found in toba batak in Sumatra and mandar of Sulawesi,K-FTC181 and K-MF10925are found in individuals from Thailand and Vietnam respectively. These branches share a common ancestor with the common NO-M214 at K-F549. ^{[9] [10]}

Origin

According to geneticist Spencer Wells, haplogroup K probably originated in the Middle East or Central Asia, possibly in the vicinity of Iran or Pakistan. ^[5] However, Karafet et al. (2014) proposed that "rapid diversification ... of K-M526", also known as K2, likely occurred in Southeast Asia and later expanded to mainland Asia, although they could not rule out that it might have arisen in Eurasia and later went extinct there, and that either of these scenarios are "equally parsimonius". ^[11]

Discoveries since 2016

Before 2016, many authorities considered that the SNP M2308 was always found in conjunction with SNPs such as M2313 and M214. ^[3] However, researchers such as G. David Poznik discovered examples of Y-DNA that had some, but not all, of the SNPs peculiar to NO (M214), but also lacked SNPs identifying other primary subclades of K2 (M526). ^[3] Poznik et al. 2016 therefore identified K2a (M2308), K-M2313 and NO (M214) as "parent", "child" and "grandchild" clades respectively. (While Poznik used the name "K2a1" for K-M2313, this has not been widely adopted – possibly because K2a1 has sometimes been used as an alternate name for other, less closely related haplogroups.) Poznik et al. also found that K-Y28301 – which has living members in India – is descended from K-M2313. The above findings by Poznik et al. were reiterated by the work of Moreno-Mayar et al. in 2018. ^[12]

As of 2018, authorities like the International Society of Genetic Genealogy (ISOGG) have not integrated the discoveries of Poznik et al.

• ISOGG has continued to use the names "K2a" and "NO" in reference to an undifferentiated clade combining K2a (M2308) and K-M2313 (i.e. Poznik's K2a and "K2a1"), ^[13] while referring to NO-M214 as "NO1".

There is evidence of at least two additional primary branches within K-M2308 (Poznik: K2a) and/or K-M2313 (Poznik: K2a1).

• YFull alone lists a clade, known only as K-Y28299, branching from an undifferentiated K-M2308/K-M2313 (YFull name: K-M2335). In addition, a newer, more divergent subclade named K-Y28301 is a primary branch of K-Y28299, according to YFull. Furthermore, according to both Poznik and Moreno-Mayar, K-Y28301 is also descended from K-M2313, ^{[12] [3]} suggesting the following lineage: K-M2313 > K-Y28299 > K-Y28301. Three living individuals in India have been found to carry K-Y28299* or K-Y28301. ^[14] (As of 2018, ISOGG had not incorporated K-Y28299 or K-Y28301.)
• ISOGG alone lists a haplogroup known only as "NO1~" [ sic ] identified by the SNP CTS707/M2306, ^[13] as a sibling of NO-M214. (Under the taxonomic conventions used by ISOGG, a tilde [~] indicates a distinct haplogroup, the position of which in the phylogeny is as yet unclear.) NO1~ is likely a primary branch of either K-M2313 or NO-M214, because, as of 2018, YFull regards CTS707/M2306 as synonymous with M214/PAGE39/PAGES00039, and yet NO1~ is also not (according to ISOGG) ancestral to either Haplogroup N (M231) or Haplogroup O (M175).

After 2022, more detection results were found in South Asia and Southeast Asia, and new branches( Includes scientific and personal samples)were added to the downstream of K-F549. ^{[9] [10]}

Phylogenetic tree

K2aK-M2308 (M2308, CTS11667)  ^[3]

• K-M2313 (Z4952/M2339/E482, F549/M2335/S22380/V4208, ^{[Note 1]} Z4842/M2308/V1371, F650/M2346,
  Z4858/M2313/S11799/E295/E205, Z4829) ^{[3] [1]}
  • K-FTC181 ^[10]
  • K-MF106925 ^[10]
  • K-Y28394  ^{[Note 2]} (Y28299/Y28355, Y28357, Y28412, etc.)
    • K-Y28301  ^{[Note 3]} (Y28301/Y28328, Y28358, Y28410)
    • K-F14963 ^[9]
  • NO   ^{[Note 4]} (M214/Page39, F176/M2314, CTS5858/M2325/F346, CTS11572) ^{[14] [15] [16] [3] [13]}
    • N (M231, CTS2947/M2175, Z4891, CTS10118)  ^[8]
    • O (M175/P186/P191/P196, F369/M1755, F380/M1757/S27659)  ^[8]

         ? "NO1~" ^{[Note 5]} (CTS707/M2306)  ^[13]

Notes regarding phylogenetic tree

1. Some authorities, such as ISOGG and YFull, do not yet include the separation of the subclade defined by the SNP F549/M2335/S22380/V4208 from the clade defined by the SNPs M2308 and Z4842, identified by Poznik et al. (2016).
2. Position of K-Y28299 and its subclade K-Y28301 based on YFull 2018. In addition, while K-Y28299 is not specifically mentioned by researchers such as Poznik et al. (2016) and Moreno-Mayar et al. (2018), these sources do state that K-Y28301 is a lineal descendant of K-M2313.
3. No phylogenetic name as of 2018; according to YFull, K-Y28301 is a primary branch of K-Y28299. In addition, according to Poznik et al. 2016 and Moreno-Mayar et al. 2018, K-Y28301 is a descendant of K-M2313.
4. ISOGG 2018 name NO1.
5. "NO1~" is a temporary name used by ISOGG (2018). Approximate position only; YFull (2018) regards CTS707/M2306 as concurrent with M214/Page39, suggesting that NO1~ is a primary branch of K-M2313 or NO-M214.

Distribution

K2a* (K-M2308*)

K2a* has been found only in the Paleolithic remains mentioned above:

• "Ust'-Ishim man" ^[3] – the name given to 45,000-year-old remains of one of the early modern humans to inhabit western Siberia. ^[17] The fossil was named after the Ust'-Ishim District of Siberia where it had been discovered. ^[17] Until 2016, Ust'-Ishim man was classified as belonging to Haplogroup K2*.
• "Oase-1", the remains of an individual who lived approximately 37,800 years ago, in Eastern Europe (modern Romania). ^[3]

K-M2313

K-M213(xNO-M214) Individuals were found in samples from South and Southeast Asia ^{[9] [10]}

NO (M214)

Main article: Haplogroup NO

Basal examples of haplogroup NO* have not been identified.

Subclades of haplogroup NO include a majority of living males in East Asia, South East Asia and northern Eurasia.

K-Y28394

K-Y28299(xY28301) has been found in Individuals from India and Pakistan. ^[8]

K-Y28301, a subclade of K-Y28299, has been found in living individuals with their origins in Andhra Pradesh and Arunachal Pradesh India. ^[8]

K-F14963 is another branch of Y28394,distributed the Toba Batak and Mandar and some other people in Southeast Asia. ^{[9] [10]}

K-FTC181, K-MF10925

Found in Thailand and Vietnam. ^[10]

See also

• Human Y-chromosome DNA haplogroup
• Genealogical DNA test
• Y-chromosome haplogroups in populations of the world

Footnotes

1. YFull Haplogroup YTree v5.06 at 25 September 2017
2. Karmin, Monika; Saag, Lauri; Vicente, Mário; et al. (2015). "", "A recent bottleneck of Y chromosome diversity coincides with a global change in culture". Genome Research. 25 (4): 459–466. doi:10.1101/gr.186684.114. PMC   4381518 . PMID   25770088.
3. Poznik, G David; Xue, Yali; Mendez, Fernando L; Willems, Thomas F; Massaia, Andrea; Wilson Sayres, Melissa A; Ayub, Qasim; McCarthy, Shane A; Narechania, Apurva; Kashin, Seva; Chen, Yuan; Banerjee, Ruby; Rodriguez-Flores, Juan L; Cerezo, Maria; Shao, Haojing; Gymrek, Melissa; Malhotra, Ankit; Louzada, Sandra; Desalle, Rob; Ritchie, Graham R S; Cerveira, Eliza; Fitzgerald, Tomas W; Garrison, Erik; Marcketta, Anthony; Mittelman, David; Romanovitch, Mallory; Zhang, Chengsheng; Zheng-Bradley, Xiangqun; Abecasis, Gonçalo R; McCarroll, Steven A; Flicek, Paul; Underhill, Peter A; Coin, Lachlan; Zerbino, Daniel R; Yang, Fengtang; Lee, Charles; Clarke, Laura; Auton, Adam; Erlich, Yaniv; Handsaker, Robert E; Bustamante, Carlos D; Tyler-Smith, Chris (June 2016). "Punctuated bursts in human male demography inferred from 1,244 worldwide Y-chromosome sequences". Nature Genetics. 48 (6): 593–599. doi:10.1038/ng.3559. PMC   4884158 . PMID   27111036.
4. Karafet, Tatiana M.; Mendez, Fernando L.; Sudoyo, Herawati; Lansing, J. Stephen; Hammer, Michael F. (March 2015). "Improved phylogenetic resolution and rapid diversification of Y-chromosome haplogroup K-M526 in Southeast Asia". European Journal of Human Genetics. 23 (3): 369–373. doi:10.1038/ejhg.2014.106. PMC   4326703 . PMID   24896152.
5. Wells, Spencer (20 November 2007). Deep Ancestry: The Landmark DNA Quest to Decipher Our Distant Past. National Geographic Books. p. 79. ISBN   978-1-4262-0211-7. "Given the widespread distribution of K, it probably arose somewhere in the Middle East or Central Asia, perhaps in the region of Iran or Pakistan."
6. Genetic Homeland, 2018, DNA Marker Index Chromosome Y M2308 (6 March 2018).
7. Genetic Homeland, 2018, DNA Marker Index Chromosome Y M2313 (6 March 2018).
8. YFull YTree v5.08, 2017, "K-M2335" (9 December 2017); PhyloTree, 2017, "Details of the Y-SNP markers included in the minimal Y tree" (9 December 2017); GeneticHomeland.com, 2016, DNA Marker Index Chromosome Y V4208 (9 December 2017).
9. Karmin, Monika; Flores, Rodrigo; Saag, Lauri; Hudjashov, Georgi; Brucato, Nicolas; Crenna-Darusallam, Chelzie; Larena, Maximilian; Endicott, Phillip L.; Jakobsson, Mattias; Lansing, J. Stephen; Sudoyo, Herawati; Leavesley, Matthew; Metspalu, Mait; Ricaut, François-Xavier; Cox, Murray P. (2 March 2022). "Episodes of Diversification and Isolation in Island Southeast Asian and Near Oceanian Male Lineages". Molecular Biology and Evolution. 39 (3) msac045. doi:10.1093/molbev/msac045. ISSN   1537-1719. PMC   8926390 . PMID   35294555.
10. "Welcome to FamilyTreeDNA Discover". FamilyTreeDNA Discover. Retrieved 8 October 2025.
11. Karafet TM, Mendez FL, Sudoyo H, Lansing JS, Hammer MF (March 2015). "Improved phylogenetic resolution and rapid diversification of Y-chromosome haplogroup K-M526 in Southeast Asia". European Journal of Human Genetics. 23 (3): 369–73. doi:10.1038/ejhg.2014.106. PMC   4326703 . PMID   24896152. "This pattern leads us to hypothesize a southeastern Asian origin for P-P295 and a later expansion of the ancestor of subhaplogroups R and Q into mainland Asia. An alternative explanation would involve an extinction event of ancestral P-P295* chromosomes everywhere in Asia. These scenarios are equally parsimonious. They involve either a migration event (P* chromosomes from Indonesia to mainland Asia) or an extinction event of P-P295* paragroup in Eurasia."
12. Moreno-Mayar JV, Vinner L, de Barros Damgaard P, de la Fuente C, Chan J, Spence JP, Allentoft ME, Vimala T, Racimo F, Pinotti T, Rasmussen S, Margaryan A, Iraeta Orbegozo M, Mylopotamitaki D, Wooller M, Bataille C, Becerra-Valdivia L, Chivall D, Comeskey D, Devièse T, Grayson DK, George L, Harry H, Alexandersen V, Primeau C, Erlandson J, Rodrigues-Carvalho C, Reis S, Bastos MQR, Cybulski J, Vullo C, Morello F, Vilar M, Wells S, Gregersen K, Hansen KL, Lynnerup N, Mirazón Lahr M, Kjær K, Strauss A, Alfonso-Durruty M, Salas A, Schroeder H, Higham T, Malhi RS, Rasic JT, Souza L, Santos FR, Malaspinas AS, Sikora M, Nielsen R, Song YS, Meltzer DJ, Willerslev E., "Early human dispersals within the Americas", Science, 2018 vol. 362, no. 6419 (7 December).
13. ISOGG, Y-DNA Haplogroup Tree 2018 (17 January 2018).
14. YFull YTree v5.08, 2017, "K-M2335" (9 December 2017)
15. PhyloTree, 2017, "Details of the Y-SNP markers included in the minimal Y tree" (9 December 2017)
16. GeneticHomeland.com, 2016, DNA Marker Index Chromosome Y V4208 (9 December 2017).
17. Callaway, Ewen (23 October 2014). "45,000-Year-Old Man's Genome Sequenced". Scientific American.