All mtDNA haplogroups found outside of Africa are descendants of either haplogroup N or its sibling haplogroup M. M and N are the signature haplogroups that define the out of Africa migration and the subsequent spread to rest of the world. The global distribution of haplogroups N and M, indicates that very likely, there was one particularly major prehistoric migration of humans out of Africa, and both N and M were part of the same colonization process.
An enormous haplogroup spanning many continents, the macro-haplogroup N, like its sibling M, is a descendant of haplogroup L3. There is widespread agreement in the scientific community concerning the African ancestry of haplogroup L3 (haplogroup N’s parent clade). However, whether or not the mutations which define haplogroup N itself first occurred within Asia or Africa has been a subject for ongoing discussion and study.
Haplogroup N is derived from the ancestral L3 haplotype that represents the ‘Out of Africa’ migration. Haplogroup N is the ancestral haplogroup to almost all European and Oceanian haplogroups in addition to many Asian and Amerindian ones. It is believed to have arisen at a similar time to haplogroup M.
MtDNA haplogroup R is a very extended mitochondrial DNA (mtDNA) haplogroup and is the most common macro-haplogroup in West Eurasia. It is a descendant of macro-haplogroup N. Among its descendant haplogroups are B, U (and thus K), F, R0 (and thus HV, H, and V), and the ancestral haplogroup of J and T. As of June 2009, the most recent study dates the origin of haplogroup R to 66.8kya with a 95% confidence interval of 52.6-81kya.
South Asia lies on the way of earliest dispersals from Africa and is therefore a valuable well of knowledge on early human migration. The analysis of the indigenous haplogroup R lineages in India points to a common first spread of the root haplotypes of M, N, and R along the southern route some 60–70 kya.
Haplogroup R has wide diversity and antiquity among varied ethnic status and different language families in South Asia. In Indian western region among the castes and southern region among the tribes show higher haplogroup diversity than the other regions, possibly suggesting their autochthonous status.
MtDNA Haplogroup U descends from a woman in the mtDNA haplogroup R branch of the phylogenetic tree, who lived around 55,000 years ago. It is widely distributed across Western Eurasia, North Africa, and South Asia.
Subclades such as Haplogroup U6, are also found at moderate to low frequencies in the Northwest and East Africa, due to a back migration from Asia around 27,000 years ago. In spite of the highest diversity of Iberian U6, Maca-Meyer argues for an Near East origin of this clade based on the highest diversity of subclade U6a in that region, where it would have arrived from West Asia. She estimates the age of U6 between 25,000 and 66,000 years BP.
Controversy surrounds the existence of mitochondrial DNA haplogroup N in Africa. Some researchers have suggested that haplogroups N probably originated in Africa (Quintana-Murci et al, 1999; Sun el al,2005). Quintana-Murci et al (1999) has suggested that haplogroup N probably originated in Ethiopia before the out of Africa migration.
Other researchers believe that haplogroup Nin Africa is the result of a back migration. The cra-niofacial and molecular evidence does not supportthis conclusion. The molecular evidence indicatesthat haplogroup N is found across Africa from Eastto West on into India where it was deposited by Dravidian speakers (Winters, 2007, 2008).
Archaeogenetics is the use of genetics, ar-chaeology and linguistics to explain and discuss theorigin and spread of Homo sapiens. Using thismethodology we can gain valuable insight into hu-man history and population movements in prehis-toric times.
In this paper we will examine the spread of haplogroup N from Africa to Eurasia. It will either support an African origin or, back migration for the presence of the N haplogroup in Africa
Origin and Spread of Haplogroup N
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