What is subclade testing?
Subclade testing can provide increased resolution of your placement on the Y-chromosome phylogenetic tree. Before your subclade can be determined, you must first know what haplogroup you fall into. Haplogroups are defined by a unique mutation event such as a single nucleotide polymorphism, or SNP. These SNPs mark the branch of a haplogroup, and indicate that all descendents of that haplogroup at one time shared a common ancestor. The Y-DNA SNP mutation has been passed from father to son over thousands of years. Over time, additional SNPs may occur within a haplogroup, leading to a new lineage. These new lineages are considered subclades of the haplogroup. Each time a new mutation occurs, there is a new branch in the haplogroup, and therefore a new subclade. By testing for the presence of SNPs that have been identified as being indicative of a subclade within a haplogroup, you can now determine which specific subclade you belong to within your previously determined haplogroup.
What are the subclades of Haplogroup L?
The majority of L haplogroups can be found within the Indian subcontinent, and along with haplogroups H and R2 account for more than one-third of Indian Y-chromosomes (Kivisild et al. 2003a). Haplogroup L also occurs in the Middle East, Central Asia, Northern Africa, and along the Mediterranean coast of Europe. Currently, Haplogroup L shows a total of seven separate lineages: L*, L1, L2*, L2a, L2b, L3*, and L3a.
Description of the panel
The Y-DNA Haplogroup L Subclade Test consists of a panel of seven SNP markers. These markers are used to define the seven different subclades in Haplogroup L. The location of the SNP, the actual mutation that is detected, and the subclade that they define is listed below for each of the seven markers.
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Location of SNP
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Mutation
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Haplogroup L subclade
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M20
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A>G
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L
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M76
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T>G
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L1
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M274
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C>T
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L2b
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M317
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-GA
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L2
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M349
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G>T
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L2a
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M357
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C>A
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L3
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PK3
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T>C
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L3a
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Description of the subclades
Since few studies have included subclade testing for Haplogroup L, there is currently limited information about the distinct lineages within this haplogroup. The tradeoff to this is that any new information on these subclades may play an important role in advancing understanding of the genetic and social history of the populations that settled India. The information that is known about the specific subclades is summarized below.
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SNP
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Haplogroup L subclade
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Comments
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M20
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L*
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- Mostly found in Pakistan (13.1%; Sengupta et al. 2006)
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- L* is also found in Lebanon where it is highest in the Druze followed by Christian and then Muslim populations (Zalloua et al 2008)
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M76
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L1
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- L1 is the most common subclade in India (6.3%, Sengupta et al 2006)
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- This subclade likely arose within the boundaries of present-day India
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- Current data suggest that L1 underwent early diversification in South India then expanded toward the peripheral regions of the country
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- The most recent estimate is that the expansion time of this subclade spans at least the early Halocene, therefore well before the Neolithic and the spread of farming
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- Similarities in phylogeography and microsatellite varition with Haplogroups R1a1 and R2 suggest a common demographic history
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- Seems to be more predominant in Dravidian speakers, although this is not a consistent observation
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M317
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L2*
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- Has been detected in Southern Europe and Anatolia
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M349
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L2a
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- This subclade is sometimes called "Mediterranean" as it occurs in southern Europe from Portugal to Turkey
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M274
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L2b
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- Details of this subclade will be added once they become available
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M357
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L3*
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- Occurs with intermediate frequency in Pakistan, in the Burusho and Pashtun populations
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PK3
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L3a
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- In Pakistan, found solely in the Kalash population (23%; Mohyuddin et al. 2006)
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