|Possible time of origin||25,000-30,000 years BP |
|Possible place of origin||Iran / Iraq, South Asia (Genebase 2006) or Sogdiana, Central Asia|
|Defining mutations||M11, M20, M61, M185, L656, L863, L878, L879 (Krahn & FTDNA 2013)|
|Highest frequencies||South Asians, Burusho, Kalash, Pashtuns, Tamil Kallars, Afshar village, Al-Raqqah, east Balochistan, northern Afghanistan, Chechens, South Tyrol|
In molecular evolution, a haplogroup (from the Greek: ἁπλούς, haploûs, "onefold, single, simple") is a group of similar haplotypes that share a common ancestor having the same single nucleotide polymorphism (SNP) mutation in all haplotypes. Haplogroup L-M20 is a Y-chromosome DNA haplogroup, found in South Asia, Western Asia and Europe and is defined by SNPs M11, M20, M61 and M185.
- 1 Origins
- 2 Distribution
- 3 Phylogenetics
- 4 See also
- 5 References
- 6 External links
Haplogroup L-M20 is associated with South Asia. It has also been found at low frequencies among populations of Central Asia, Southwest Asia, and Southern Europe along the coast of the Mediterranean Sea. It is a descendant haplogroup of haplogroup K-M9, and is believed to have first appeared approximately 30,000 years ago. Gareth Henson, administrator of the Haplogroup T project at FTDNA, has theorized "I think both T and L originated in the Iraq/Iran region...the branches of L all went in different directions (L1 southeast, L2 west and L3 northeast)."
Sengupta 2006 discovered three subbranches of haplogroup L: L-M76, L-M317, and L-M357. All three are present in Pakistan, but only L-M76 is regularly found in India. They make a case for an indigenous origin of L-M76 in India, by arguing that the spatial distributions of both L-M76 HG frequency and associated microsatellite variance show a pattern of spread emanating from southern India. By linking haplogroup L-M76 to the Dravidian speakers, they simultaneously argue for an Indian origin of Dravidian languages (Sengupta 2006).
Preliminary evidence gleaned from non-scientific sources, such as individuals who have had their Y-chromosomes tested by commercial labs (Henson, Hrechdakian & FTDNA 2013), suggests that most European examples of Haplogroup L-M20 might belong to the subclade L-M317, which is, among South Asian populations, generally the rarest of the subclades of Haplogroup L.
Haplogroup L-M20 is currently present in the Indian population at an overall frequency of ca. 7-15%.[Footnote 1] The presence of haplogroup L-M20 is quite rare among tribal groups (ca. 5,6-7%) (Cordaux 2004, Sengupta 2006, and Thamseem 2006).
Earlier studies (e.g. Wells 2001) report a very high frequency (approaching 50%) of Haplogroup L-M20 in South India appear to have been due to extrapolation from data obtained from a sample of 84 Kallars, a Tamil-speaking warrior caste of Tamil Nadu, among whom 40 (approx. 48%) displayed the M20 mutation that defines Haplogroup L.
A study on the Siddis and nearby populations have reported high L-M11 frequencies in some populations (Shah 2011), indicating Indian Siddis are African descendants with obvious South Asian admixture. 68% in the Korova aka Korava tribe from Uttara Kannada in Karnataka, 38% in the Bharwad tribe from Junagarh district in Gujarat, 21% in Charan tribe from Junagarh district in Gujarat and 17% in the Kare Vokkal tribe from Uttara Kannada in Karnataka. Also found at low frequency in other populations from Junagarh district and Uttara Kannada.
The highest frequency and diversity of haplogroup L-M20 can be found among the Siddi ethnic group in Pakistan and India. L-M357 is found frequently among Burusho (approx. 12% (Firasat 2007)) and Pashtuns (approx. 7% (Firasat 2007)), with a moderate distribution among the general Pakistani population (approx. 2% (Firasat 2007)).
L-M20 was found in 51% of Syrians from Al-Raqqah, a northern Syrian city in which its previous inhabitants have been wiped out by the Mongols and repopulated in recent times by local Bedouin populations and Chechen war refugees (El-Sibai 2009). In a small sample of Israeli Druze haplogroup L-M20 was found in 7 out of 20 (35%). However, studies done on bigger samples showed that L-M20 averages 5% in Israeli Druze,[Footnote 2] 8% in Lebanese Druze,[Footnote 3] and it was not found in a sample of 59 Syrian Druze. Haplogroup L-M20 has been found in 2.0% (1/50) (Wells 2001) to 5.25% (48/914) of Lebanese (Zalloua 2008).
|Syria||51.0% (33/65) of Syrians in Al-Raqqah, 31.0% of Eastern Syrians||El-Sibai 2009|
|Iran||3.4% L-M76 (4/117) and 2.6% L-M317 (3/117)
for a total of 6.0% (7/117) haplogroup L-M20 in southern Iran
3.0% (1/33) L-M357 in northern Iran
|Turkey||57% in Afshar village, 12% (10/83) in Black Sea Region, 4.2% (1/523 L-M349 and 21/523 L-M11(xM27, M349))||Cinnioğlu 2004 and Gokcumen 2008|
|Southeastern Turkey||3.2% in Kurds||Flores 2005|
|Iraq||3.1% (2/64) L-M22||Sanchez 2005|
|Daghestan||10% of Chechens, 9.5% (4/42) of Avars, 3.7% (1/27) of Chamalins||Yunusbaev 2006 and Caciagli 2009|
|Balkarians||5.3% (2/38) L-M317||Battaglia 2008|
|Armenians||1.63% (12/734) to 4.3% (2/47)||Weale 2001 and Wells 2001|
|Georgians||1.5% (1/66) L-M357(xPK3) to 1.6% (1/63) L-M11||Battaglia 2008 and Semino 2000|
|Omanis||1% L-M11||Luis 2004|
|Qataris||2.8% (2/72 L-M76)||Cadenas 2008|
|UAE Arabs||3.0% (4/164 L-M76 and 1/164 L-M357)||Cadenas 2008|
|Saudi Arabians||1.91% (2/157=1.27% L-M76 and 1/157=0.64% L-M357)||AbuAmero 2009|
|Pamiris||10.1% (10/99) (including 7/44=16% of Shugnanis,
3/25=12% of Ishkashimis, 0/30 Bartangis)
|Yagnobis||9.7% (3/31)||Wells 2001|
|Bukharan Arabs||9.5% (4/42)||Wells 2001|
|Tajiks||9.0% (7/78)||Wells 2001|
|Karakalpaks||4.5% (2/44)||Wells 2001|
|Uyghurs||4.4% (3/68)||Karafet 2001 and Hammer 2005[Footnote 4]|
|Uzbeks||3.0% (11/366) to 3.7% (2/54)||Wells 2001 and Karafet 2001|
|Kazan Tatars||2.6% (1/38)||Wells 2001|
|Hui||1.9% (1/54)||Karafet 2001|
|Bashkirs||0.64% (3/471)||Lobov 2009|
Researchers studying samples of Y-DNA from populations of Eastern Asia have rarely tested their samples for any of the mutations that define Haplogroup L. However, mutations for Haplogroup L have been tested and detected in samples of Balinese (13/641 = 2.0% L-M20) and Koreans (3/506 = 0.6% L-M20).
An article by O. Semino et al. published in the journal Science (Volume 290, 10 November 2000) reported the detection of the M11-G mutation, which is one of the mutations that defines Haplogroup L, in approximately 1% to 3% of samples from Georgia, Greece, Hungary, Calabria, and Andalusia. The sizes of the samples analyzed in this study were generally quite small, so it is possible that the actual frequency of Haplogroup L-M20 among Mediterranean European populations may be slightly lower or higher than that reported by Semino et al., but there seems to be no study to date that has described more precisely the distribution of Haplogroup L-M20 in Southwest Asia and Europe.
|South Tyrol||8.9% of Ladin speakers from Val Badia, 8.3% of Val Badia, 2.9% of Puster Valley, 2.2% of German speakers from Val Badia, 2% of German speakers from Upper Vinschgau, 1.9% of German speakers from Lower Vinschgau and 1.7% of Italian speakers from Bolzano||Pichler 2006 and Thomas 2007.|
|Portugal||5.0% of Coimbra||Beleza 2006|
|Estonia||L2 is found in 5.3%, 3.5%, 1.4% and 0.8% of Estonians||Scozzari 2001 and Lappalainen 2007|
|Flanders||L1a*: 3.17% of Mechelen 2.4% of Turnhout and 1.3% of Kempen. L1b*: 0.74% of West Flanders and East Flanders||Larmuseau 2010 and Larmuseau 2011|
|Gipuzkoa||L1b is found in 1.7% of Gipuzkoans||Young 2011|
L-M27 is found frequently in Indians, Sri Lankans, and Siddis, with a moderate distribution in other populations of Pakistan, southern Iran, and Arabia but also in European populations.
L-M349 is principally found in Europe.
L-M357 is found frequently among Burushos, Kalashas, Chechens and Pashtuns, with a moderate distribution among other populations in Pakistan, Georgia, northern Iran, India, the UAE, and Saudi Arabia.
In Y-chromosome phylogenetics, subclades are the branches of haplogroups. These subclades are also defined by single nucleotide polymorphisms (SNPs) or unique event polymorphisms (UEPs).
Prior to 2002, there were in academic literature at least seven naming systems for the Y-Chromosome Phylogenetic tree. This led to considerable confusion. In 2002, the major research groups came together and formed the Y-Chromosome Consortium (YCC). They published a joint paper that created a single new tree that all agreed to use. Later, a group of citizen scientists with an interest in population genetics and genetic genealogy formed a working group to create an amateur tree aiming at being above all timely. The table below brings together all of these works at the point of the landmark 2002 YCC Tree. This allows a researcher reviewing older published literature to quickly move between nomenclatures.
|YCC 2002/2008 (Shorthand)||(α)||(β)||(γ)||(δ)||(ε)||(ζ)||(η)||YCC 2002 (Longhand)||YCC 2005 (Longhand)||YCC 2008 (Longhand)||YCC 2010r (Longhand)||ISOGG 2006||ISOGG 2007||ISOGG 2008||ISOGG 2009||ISOGG 2010||ISOGG 2011||ISOGG 2012|
Original research publications
The following research teams per their publications were represented in the creation of the YCC Tree.
|This section is empty. You can help by adding to it. (January 2013)|
There are several confirmed and proposed phylogenetic trees available for haplogroup L-M20. The scientifically accepted one is the Y-Chromosome Consortium (YCC) one published in Karafet 2008 and subsequently updated. A draft tree that shows emerging science is provided by Thomas Krahn at the Genomic Research Center in Houston, Texas. The International Society of Genetic Genealogy (ISOGG) also provides an amateur tree.
|This section requires expansion. (January 2013)|
The Genomic Research Center draft tree
- L-M20 M11, M20, M61, M185, L656, L863, L878, L879
- L-M22 M22, M295, PAGES00121
- L-M317 M317, L655
- L-M349 M349
- L-M274 M274
- L-L1310 L1310
- L-L1304 L1304
- L-M27 M27, M76, P329.1, L1318, L1319, L1320, L1321
- L-M357 M357
- L-PK3 PK3
- L-L1305 L1305, L1306, L1307
- L-M317 M317, L655
- L-L595 L595
- L-L864 L864, L865, L866, L867, L868, L869, L870, L877
- L-M22 M22, M295, PAGES00121
The Y-Chromosome Consortium tree
This is the official scientific tree produced by the Y-Chromosome Consortium (YCC). The last major update was in 2008 (Karafet 2008). Subsequent updates have been quarterly and biannual. The current version is a revision of the 2010 update.
|This section requires expansion. (January 2013)|
The 2012 ISOGG tree
The subclades of Haplogroup L-M20 with their defining mutation(s), according to the 2011 ISOGG tree are provided below.
Y-DNA L Subclades
Y-DNA Backbone Tree
|Evolutionary tree of human Y-chromosome DNA (Y-DNA) haplogroups [n 1] [n 2]|
|A00||A0-T [n 3]|
|L||T||NO (K2a)||K2b[n 5]||K2c||K2d||K2e [n 6]|
- Indian Siddis: African Descendants with Indian Admixture
- Karafet, Tatiana M.; Hallmark, Brian; Cox, Murray P.; Sudoyo, Herawati; Downey, Sean; Lansing, J. Stephen; Hammer, Michael F. (2010). "Major East–West Division Underlies Y Chromosome Stratification across Indonesia". Mol. Biol. Evol. 27 (8): 1833–1844. doi:10.1093/molbev/msq063. PMID 20207712.
- Soon-Hee Kim, Ki-Cheol Kim, Dong-Jik Shin, Han-Jun Jin, Kyoung-Don Kwak, Myun-Soo Han, Joon-Myong Song, Won Kim and Wook Kim. "High frequencies of Y-chromosome haplogroup O2b-SRY465 lineages in Korea: a genetic perspective on the peopling of Korea". Investigative Genetics 2011 (2): 10. doi:10.1186/2041-2223-2-10. PMC 3087676. PMID 21463511.
- "Y-DNA Haplotree". Family Tree DNA uses the Y-Chromosome Consortium tree and posts it on their website.
- Abu-Amero, Khaled K; Hellani, Ali; González, Ana M; Larruga, Jose M; Cabrera, Vicente M; Underhill, Peter A (2009). "Saudi Arabian Y-Chromosome diversity and its relationship with nearby regions". BMC Genetics 10: 59. doi:10.1186/1471-2156-10-59. PMC 2759955. PMID 19772609.
- Basu, A.; Mukherjee, N; Roy, S; Sengupta, S; Banerjee, S; Chakraborty, M; Dey, B; Roy, M et al. (2003). "Ethnic India: A Genomic View, with Special Reference to Peopling and Structure". Genome Research 13 (10): 2277–90. doi:10.1101/gr.1413403. PMC 403703. PMID 14525929.
- Battaglia, Vincenza; Fornarino, Simona; Al-Zahery, Nadia; Olivieri, Anna; Pala, Maria; Myres, Natalie M; King, Roy J; Rootsi, Siiri et al. (2008). "Y-chromosomal evidence of the cultural diffusion of agriculture in southeast Europe". European Journal of Human Genetics 17 (6): 820–30. doi:10.1038/ejhg.2008.249. PMC 2947100. PMID 19107149.
- Beleza, Sandra; Gusmao, Leonor; Lopes, Alexandra; Alves, Cintia; Gomes, Iva; Giouzeli, Maria; Calafell, Francesc; Carracedo, Angel; Amorim, Antonio (2006). "Micro-Phylogeographic and Demographic History of Portuguese Male Lineages". Annals of Human Genetics 70 (2): 181–94. doi:10.1111/j.1529-8817.2005.00221.x. PMID 16626329.
- Caciagli, Laura; Bulayeva, Kazima; Bulayev, Oleg; Bertoncini, Stefania; Taglioli, Luca; Pagani, Luca; Paoli, Giorgio; Tofanelli, Sergio (2009). "The key role of patrilineal inheritance in shaping the genetic variation of Dagestan highlanders". Journal of Human Genetics 54 (12): 689–94. doi:10.1038/jhg.2009.94. PMID 19911015.
- Cadenas, Alicia M; Zhivotovsky, Lev A; Cavalli-Sforza, Luca L; Underhill, Peter A; Herrera, Rene J (2007). "Y-chromosome diversity characterizes the Gulf of Oman". European Journal of Human Genetics 16 (3): 374–86. doi:10.1038/sj.ejhg.5201934. PMID 17928816.
- Cinnioğlu, Cengiz; King, Roy; Kivisild, Toomas; Kalfoglu, Ersi; Atasoy, Sevil; Cavalleri, Gianpiero L.; Lillie, Anita S.; Roseman, Charles C. et al. (2004). "Excavating Y-chromosome haplotype strata in Anatolia". Human Genetics 114 (2): 127–48. doi:10.1007/s00439-003-1031-4. PMID 14586639.
- Cordauxyear=2004, Richard; Aunger, Robert; Bentley, Gillian; Nasidze, Ivane; Sirajuddin, S.M.; Stoneking, Mark (2004). "Independent Origins of Indian Caste and Tribal Paternal Lineages". Current Biology 14 (3): 231–5. doi:10.1016/j.cub.2004.01.024. PMID 14761656.
- El-Sibai, Mirvat; Platt, Daniel E.; Haber, Marc; Xue, Yali; Youhanna, Sonia C.; Wells, R. Spencer; Izaabel, Hassan; Sanyoura, May F. et al. (2009). "Geographical Structure of the Y-chromosomal Genetic Landscape of the Levant: A coastal-inland contrast". Annals of Human Genetics 73 (6): 568–81. doi:10.1111/j.1469-1809.2009.00538.x. PMC 3312577. PMID 19686289.
- Firasat, Sadaf; Khaliq, Shagufta; Mohyuddin, Aisha; Papaioannou, Myrto; Tyler-Smith, Chris; Underhill, Peter A; Ayub, Qasim (2007). "Y-chromosomal evidence for a limited Greek contribution to the Pathan population of Pakistan". European Journal of Human Genetics 15 (1): 121–6. doi:10.1038/sj.ejhg.5201726. PMC 2588664. PMID 17047675.
- Karafet, Tatiana; Xu, Liping; Du, Ruofu; Wang, William; Feng, Shi; Wells, R.S.; Redd, Alan J.; Zegura, Stephen L.; Hammer, Michael F. (2001). "Paternal Population History of East Asia: Sources, Patterns, and Microevolutionary Processes". The American Journal of Human Genetics 69 (3): 615–28. doi:10.1086/323299. PMC 1235490. PMID 11481588.
- Lappalainen, T.; Laitinen, V.; Salmela, E.; Andersen, P.; Huoponen, K.; Savontaus, M.-L.; Lahermo, P. (2008). "Migration Waves to the Baltic Sea Region". Annals of Human Genetics 72 (3): 337–48. doi:10.1111/j.1469-1809.2007.00429.x. PMID 18294359.
- Larmuseau, Maarten H.D.; Vanderheyden, Nancy; Jacobs, Manon; Coomans, Monique; Larno, Lucie; Decorte, Ronny (2010). "Micro-geographic distribution of Y-chromosomal variation in the central-western European region Brabant". Forensic Science International: Genetics 5 (2): 95–9. doi:10.1016/j.fsigen.2010.08.020. PMID 21036685.
- Larmuseau, Maarten HD; Ottoni, Claudio; Raeymaekers, Joost AM; Vanderheyden, Nancy; Larmuseau, Hendrik FM; Decorte, Ronny (2011). "Temporal differentiation across a West-European Y-chromosomal cline: Genealogy as a tool in human population genetics". European Journal of Human Genetics 20 (4): 434–40. doi:10.1038/ejhg.2011.218. PMC 3306861. PMID 22126748.
- Luis, J; Rowold, D; Regueiro, M; Caeiro, B; Cinnioglu, C; Roseman, C; Underhill, P; Cavallisforza, L; Herrera, R (2004). "The Levant versus the Horn of Africa: Evidence for Bidirectional Corridors of Human Migrations". The American Journal of Human Genetics 74 (3): 532–44. doi:10.1086/382286. PMC 1182266. PMID 14973781.
- Pichler, Irene; Mueller, Jakob C.; Stefanov, Stefan A.; De Grandi, Alessandro; Beu Volpato, Claudia; Pinggera, Gerd K.; Mayr, Agnes; Ogriseg, Martin et al. (2006). "Genetic Structure in Contemporary South Tyrolean Isolated Populations Revealed by Analysis of Y-Chromosome, mtDNA, and Alu Polymorphisms". Human Biology 81 (5–6): 875–98. doi:10.3378/027.081.0629. PMID 20504204.
- Qamar, Raheel; Ayub, Qasim; Mohyuddin, Aisha; Helgason, Agnar; Mazhar, Kehkashan; Mansoor, Atika; Zerjal, Tatiana; Tyler-Smith, Chris; Mehdi, S. Qasim (2002). "Y-Chromosomal DNA Variation in Pakistan". The American Journal of Human Genetics 70 (5): 1107–24. doi:10.1086/339929. PMC 447589. PMID 11898125.
- Regueiro, M.; Cadenas, A.M.; Gayden, T.; Underhill, P.A.; Herrera, R.J. (2006). "Iran: Tricontinental Nexus for Y-Chromosome Driven Migration". Human Heredity 61 (3): 132–43. doi:10.1159/000093774. PMID 16770078.
- Sahoo, S.; Singh, A.; Himabindu, G.; Banerjee, J.; Sitalaximi, T.; Gaikwad, S.; Trivedi, R.; Endicott, P.; Kivisild, T.; Metspalu, M.; Villems, R.; Kashyap, V. K. (2006). "A prehistory of Indian Y chromosomes: Evaluating demic diffusion scenarios". Proceedings of the National Academy of Sciences 103 (4): 843–8. doi:10.1073/pnas.0507714103. PMC 1347984. PMID 16415161.
- Sanchez, Juan J; Hallenberg, Charlotte; Børsting, Claus; Hernandez, Alexis; Gorlin, RJ (2005). "High frequencies of Y chromosome lineages characterized by E3b1, DYS19-11, DYS392-12 in Somali males". European Journal of Human Genetics 13 (7): 856–66. doi:10.1038/sj.ejhg.5201390. PMID 15756297.
- Scozzari, Rosaria; Cruciani, Fulvio; Pangrazio, Alessandra; Santolamazza, Piero; Vona, Giuseppe; Moral, Pedro; Latini, Veronica; Varesi, Laurent et al. (2001). "Human Y-chromosome variation in the Western Mediterranean area: Implications for the peopling of the region". Human Immunology 62 (9): 871–84. doi:10.1016/S0198-8859(01)00286-5. PMID 11543889.
- Semino, O.; Passarino, G; Oefner, PJ; Lin, AA; Arbuzova, S; Beckman, LE; De Benedictis, G; Francalacci, P et al. (2000). "The Genetic Legacy of Paleolithic Homo sapiens sapiens in Extant Europeans: A Y Chromosome Perspective". Science 290 (5494): 1155–9. doi:10.1126/science.290.5494.1155. PMID 11073453.
- Sengupta, Sanghamitra; Zhivotovsky, Lev A.; King, Roy; Mehdi, S.Q.; Edmonds, Christopher A.; Chow, Cheryl-Emiliane T.; Lin, Alice A.; Mitra, Mitashree et al. (2006). "Polarity and Temporality of High-Resolution Y-Chromosome Distributions in India Identify Both Indigenous and Exogenous Expansions and Reveal Minor Genetic Influence of Central Asian Pastoralists". The American Journal of Human Genetics 78 (2): 202–21. doi:10.1086/499411. PMC 1380230. PMID 16400607.
- Shah, Anish M.; Tamang, Rakesh; Moorjani, Priya; Rani, Deepa Selvi; Govindaraj, Periyasamy; Kulkarni, Gururaj; Bhattacharya, Tanmoy; Mustak, Mohammed S.; Bhaskar, L.V.K.S.; Reddy, Alla G.; Gadhvi, Dharmendra; Gai, Pramod B.; Chaubey, Gyaneshwer; Patterson, Nick; Reich, David; Tyler-Smith, Chris; Singh, Lalji; Thangaraj, Kumarasamy (2011). "Indian Siddis: African Descendants with Indian Admixture". The American Journal of Human Genetics 89: 154. doi:10.1016/j.ajhg.2011.05.030.
- Thamseem, Ismail; Thangaraj, Kumarasamy; Chaubey, Gyaneshwer; Singh, Vijay; Bhaskar, Lakkakula VKS; Reddy, B Mohan; Reddy, Alla G; Singh, Lalji (2006). "Genetic affinities among the lower castes and tribal groups of India: Inference from Y chromosome and mitochondrial DNA". BMC Genetics 7: 42. doi:10.1186/1471-2156-7-42. PMC 1569435. PMID 16893451.
- Thomas, Mark G; Barnes, Ian; Weale, Michael E; Jones, Abigail L; Forster, Peter; Bradman, Neil; Pramstaller, Peter P (2008). "New genetic evidence supports isolation and drift in the Ladin communities of the South Tyrolean Alps but not an ancient origin in the Middle East". European Journal of Human Genetics 16 (1): 124–34. doi:10.1038/sj.ejhg.5201906. PMID 17712356.
- Weale, Michael; Yepiskoposyan, Levon; Jager, Rolf; Hovhannisyan, Nelli; Khudoyan, Armine; Burbage-Hall, Oliver; Bradman, Neil; Thomas, Mark (2001). "Armenian Y chromosome haplotypes reveal strong regional structure within a single ethno-national group". Human Genetics 109 (6): 659–74. doi:10.1007/s00439-001-0627-9. PMID 11810279.
- Wells, R. S.; Yuldasheva, N.; Ruzibakiev, R.; Underhill, P. A.; Evseeva, I.; Blue-Smith, J.; Jin, L.; Su, B. et al. (2001). "The Eurasian Heartland: A continental perspective on Y-chromosome diversity". Proceedings of the National Academy of Sciences 98 (18): 10244–9. doi:10.1073/pnas.171305098. PMC 56946. PMID 11526236.
- Young, Kristin L.; Sun, Guangyun; Deka, Ranjan; Crawford, Michael H. (2011). "Paternal Genetic History of the Basque Population of Spain". Human Biology 83 (4): 455–75. doi:10.3378/027.083.0402. PMID 21846204.
- Zalloua, Pierre A.; Xue, Yali; Khalife, Jade; Makhoul, Nadine; Debiane, Labib; Platt, Daniel E.; Royyuru, Ajay K.; Herrera, Rene J. et al. (2008). "Y-Chromosomal Diversity in Lebanon is Structured by Recent Historical Events". The American Journal of Human Genetics 82 (4): 873–82. doi:10.1016/j.ajhg.2008.01.020. PMC 2427286. PMID 18374297.
- Genebase (2006). "Genebase Tutorials: Learn about Y-chromosome Haplogroup L".
- Krahn, Thomas; FTDNA. "FTDNA Draft Y-DNA Tree (AKA YTree)". Family Tree DNA. Retrieved 2013.
- Henson, Gareth; Hrechdakian, Peter; FTDNA (2013). "L - The Y-Haplogroup L Project". Retrieved 2013.