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Use of Y Chromosome and Mitochondrial DNA Population Structure in Tracing Human Migrations
Peter A. Underhill , Toomas Kivisild
Annual Review of Genetics, Vol. 41: 539-564 (Volume publication date December 2007)
Abstract Well-resolved molecular gene trees illustrate the concept of descent with modification and exhibit the opposing processes of drift and migration, both of which influence population structure. Phylogenies of the maternally inherited mtDNA genome and the paternally inherited portion of the nonrecombining Y chromosome retain sequential records of the accumulation of genetic diversity. Although knowledge regarding the diversity of the entire human genome will be needed to completely characterize human genetic evolution, these uniparentally inherited loci are unique indicators of gender in modulating the extant population structure. We compare and contrast these loci for patterns of continuity and discreteness and discuss how their phylogenetic diversity and progression provide means to disentangle ancient colonization events by pioneering migrants from subsequent overlying migrations. We introduce new results concerning Y chromosome founder haplogroups C, DE, and F that resolve their previous trifurcation and improve the harmony with the mtDNA recapitulation of the out-of-Africa migration.
In addition to these general patterns of consistency between the loci, several minor regional differences can be noted:
1. In contrast to the overall homogeneity of mtDNA haplogroup composition in Europe, there are remarkable differences between West and East Europe, for example, in the frequencies of Y chromosome haplogroups R1b, I1a, and I1b (85, 89, 93). 2. East European, and Central and East Asian populations share common Y chromosome genetic components, such as haplogroups N and R1a, which are not recapitulated in mtDNA phylogeography (86). 3. Y chromosomes of the Austronesianspeaking populations do not testify to a well-pronounced founder effect as evidenced from mtDNA data (44, 112). 4. Asymmetric gene flow is detectable between hunter-gatherer and agriculturalist societies in Africa (24). 5. Y chromosome data show a signal for a separate late-Pleistocene migration from Africa to Europe over Sinai as evidenced through the distribution of haplogroup E3b lineages (20, 63), which is not manifested in mtDNA haplogroup distributions.
Posts: 2007 | From: Washington State | Registered: Oct 2006
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"....haplogroup CF and DE molecular ancestors first evolved inside Africa and subsequently contributed as Y chromosome founders to pioneering migrations that successfully colonized Asia. While not proof, the DE and CF bifurcation (Figure 8d ) is consistent with independent colonization impulses possibly occurring in a short time interval."
-------------------- Black Roots. Posts: 2007 | From: Washington State | Registered: Oct 2006
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quote:Originally posted by Evergreen: Use of Y Chromosome and Mitochondrial DNA Population Structure in Tracing Human Migrations
Peter A. Underhill , Toomas Kivisild
Annual Review of Genetics, Vol. 41: 539-564 (Volume publication date December 2007)
Y chromosome data show a signal for a separate late-Pleistocene migration from Africa to Europe over Sinai as evidenced through the distribution of haplogroup E3b lineages....
Evergreen Writes:
Of course this genetic data has been supported in the anthropological record for sometime now.
Evergreen Posts:
Excavations in the Franchthi Cave, 1969-1971. Part II
"It would be nice to know if the Franchthi Neolithic people were mainly intruders,as apparently at Nea Nikomedeia where there are negroid African as well as Levantine and Anatolian similarities plus local Mesolithic additions (massive Alpine and Basic White)."
Posts: 2007 | From: Washington State | Registered: Oct 2006
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"....haplogroup CF and DE molecular ancestors first evolved inside Africa and subsequently contributed as Y chromosome founders to pioneering migrations that successfully colonized Asia. While not proof, the DE and CF bifurcation (Figure 8d ) is consistent with independent colonization impulses possibly occurring in a short time interval."
Goes back to the F-M89 bearing African group who would go onto become a founder population [for a new line of descent of what was to become the F haplogroup] in their new found location outside of mainland Africa. So, I take it that [without yet having the opportunity to read the entire study, as it seems to only be available through subscription at the moment] the CF ancestor entails some transitional UEP or insertion event that occurred some time after the M168 mutational event, but before the splitting of F(M89,P14, M213) and C(M130, M216) mutational events, assuming that the YAP+ line doesn't possess the said 'transitional marker' - but rather, occurred on an M168 line that was independent of the said transitional unique event(s). To that end, this split would have likely occurred after the spilt of the line that would eventually give rise to YAP-positive DE. If so, what are we told about this 'transitional' marker?...or, is there something else implicated in this CF ancestor examination, whose possibility I haven't yet raised?
Posts: 1947 | Registered: Sep 2005
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I have the full text and once again, it reaffirms that the origin of YAP+ is in Africa, not Asia.
Posts: 2595 | From: Vicksburg | Registered: Feb 2006
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