Haplogroup L (Y-DNA)

Haplogroup L-M20
Possible time of origin	25,000-30,000 years BP
Possible place of origin	South Asia
Ancestor	LT
Defining mutations	M11, M20, M61, M185, L656, L863, L878, L879
Highest frequencies	South Asians, Burusho, Kalash, Pashtuns, Tamil Kallars, Afshar village, Raqqa, east Balochistan, northern Afghanistan, Fascia, Venetia, South Tyrol

Haplogroup L-M20 is a human Y-DNA haplogroup, which is defined by SNPs M11, M20, M61 and M185. It is most commonly found in populations native to South Asia, especially Afghanistan, Pakistan and South India. The clade also occurs in Tajikistan and Anatolia, as well as at lower frequencies in Iran, Western Europe, Central Europe, Northeastern Europe, the Caucasus, Balkans and Central Asia. The subclade L2 (L-L595), while it is extremely rare, is seldom found outside Western Europe.

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 is Thomas Krahn at the Genomic Research Center's Draft tree Proposed Tree for haplogroup L-M20:

L-M20 is a descendant of Haplogroup LT, which is a descendant of haplogroup K-M9. According to Spencer Wells, M20 migrated into India ca. 30,000 years ago. McElreavy and Quintana-Murci, writing on the Indus Valley Civilisation, state that

One Y-chromosome haplogroup (L-M20) has a high mean frequency of 14% in Pakistan and so differs from all other haplogroups in its frequency distribution. L-M20 is also observed, although at lower frequencies, in neighbouring countries, such as India, Tajikistan, Uzbekistan and Russia. Both the frequency distribution and estimated expansion time (~7,000 YBP) of this lineage suggest that its spread in the Indus Valley may be associated with the expansion of local farming groups during the Neolithic period.

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