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Conclusion: Each of the 12,127 samples typed carried one of the three polymorphisms (YAP+, M89T, or M130T) (Table 1). In other words, they all fall into the lineage of M168T that was originally derived from Africa. Hence, no ancient non-African Y chromosome was found in the extant East Asian populations (P = 5.4 � 106 assuming a frequency of 1/1000 of local contribution in the extant populations), suggesting an absence of either an independent origin or a 1,000,000-year shared global evolution. This result indicates that modern humans of African origin completely replaced earlier populations in East Asia.
African Origin of Modern Humans in East Asia: A Tale of 12,000 Y Chromosomes, Science, 292:5519, pp. 1151-1153, Issue of 11 May 2001. Yuehai Ke, , Peter Underhill, , Mark Shriver, R Spencer Wells, Mark, Zhu Chen
The "Out-of-Africa" hypothesis suggests that anatomically modern humans originated in Africa about 100,000 years ago and then spread outward and completely replaced local archaic populations outside Africa (1, 2). This proposition has been supported by genetic evidence and archaeological findings (3-9). The replacement in Europe was supported by recent ancient DNA analyses, which ruled out the contribution of Neanderthals to modern Europeans (10, 11). However, it has been argued that the abundant hominid fossils found in China and other regions in East Asia (e.g., Peking man and Java man) demonstrate continuity, not only in morphological characters but also in spatial and temporal distributions (12-16). In this report, we test the competing hypotheses of modern Asian human origins using Y chromosome polymorphisms.
We sampled 12,127 male individuals from 163 populations across Southeast Asia, Oceania, East Asia, Siberia, and Central Asia and typed for three Y chromosome biallelic markers (YAP, M89, and M130) (17, 18) (Table 1). Being a single-locus multiple-site (i.e., haplotype) system, the Y chromosome is one of the most powerful molecular tools for tracing human evolutionary history (5, 9, 19-21). In previous Y chromosome studies, an extreme geographic structure was revealed in global populations in which the oldest clade represents Africans and the younger ones represent some Africans and all non-African populations (21).
One Y chromosome polymorphism (C to T mutation) at the M168 locus is shared by all non-African populations and was originally derived from Africa on the basis of a study of 1062 globally representative male individuals (21). The age of M168 was estimated at 44,000 years (95% confidence interval: 35,000 to 89,000 years), marking the RECENT Out-of-Africa migrations (21). Under the M168T lineage, there are three major derived sublineages defined by polymorphisms at loci YAP (Alu insertion) (5), M89 (C to T mutation), and M130 (C to T mutation, also called RPS4Y) (Fig. 1) (21, 22). Therefore, these three markers can be used to test the completeness of the replacement of modern humans of African origin in East Asia. An observation of a male individual not carrying one of the three polymorphisms would be indicative of a potential ancient origin and could possibly lead to the rejection of such completeness.
Each of the 12,127 samples typed carried one of the three polymorphisms (YAP+, M89T, or M130T) (Table 1). In other words, they all fall into the lineage of M168T that was originally derived from Africa. Hence, no ancient non-African Y chromosome was found in the extant East Asian populations (P = 5.4 � 106 assuming a frequency of 1/1000 of local contribution in the extant populations), suggesting an absence of either an independent origin or a 1,000,000-year shared global evolution. This result indicates that modern humans of African origin completely replaced earlier populations in East Asia.
It was argued that the extensive genetic data supporting the Out-of-Africa hypothesis could also be explained by the multiregional hypothesis under a version of the trellis model (23). This model suggests that a multiregional evolutionary paradigm is shared across the human range by frequent gene exchanges between continental populations since Homo erectus came out of Africa about 1 million years ago (23). It is difficult to test the trellis model with markers from mitochondrial hypervariable region (D-loop) and autosome because these markers show frequent recurrent mutations and/or recombination (24, 25), respectively. However, this can be circumvented by the application of a large number of Y chromosome biallelic markers, which escape recombination and have a low mutation rate.
It has been shown that all the Y chromosome haplotypes found outside Africa are younger than 35,000 to 89,000 years and derived from Africa (21), although this estimation is crude and depends on several assumptions. In addition, if extensive gene flow had occurred between continental populations during the past 1 million years but before the divergence between Africans and non-Africans, as suggested by the multiregionalists, the ancient Y chromosome haplotypes seen in African populations or even much older haplotypes would have been expected in East Asia, which was not observed in our data. However, this observation does not necessarily preclude the possibility of selection sweep that could erase archaic Y chromosomes of modern humans in East Asia.
On the other hand, a minor contribution from a female lineage of local origin cannot be excluded either, which should be further studied with the use of mitochondrial DNA (mtDNA) markers. Because the Y chromosome has a relatively small effective population size, it is subject to stochastic process, e.g., genetic drift, which could also lead to extinction of archaic lineages. However, in our study, with 163 populations from different regions of Asia, it is hard to imagine that all of the 163 populations should drift in the same direction.
Inconsistency of age estimations for a common ancestor with the use of mitochondrial/Y chromosome and autosome/X chromosome markers, however, creates confusion. The age estimated with the use of autosome/X chromosome genes ranges from 535,000 to 1,860,000 years (26-29), much older than those for mtDNA and Y chromosome. However, this difference in age estimation might only reflect the difference in the effective population sizes between Y chromosome/mtDNA and X chromosome/autosome (three to four times as many as the former) in the presence of bottleneck events associated with the outbound migrations from Africa, therefore disqualifying the utility of the latter in distinguishing the competing hypotheses (24, 30).
-------------------- Without data you are just another person with an opinion - Deming Posts: 12143 | From: When you have eliminated the impossible, whatever remains, however improbable | Registered: Jun 2007
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. Sadly this us true. When you go back you find as population genetic procedures improved geneticist soon discovered that the genes found in Eurasians were also found in Africans so they changed the names of haplogroups to hide the identity of Eurasian genes that in reality were African genes. Whites originated in Central Asia, as first discovered by Marc. They are attempting to manufacture the lie they were the ancient farmers of Europe and descendants of the Yamnaya and other Kushites of Anatolia.
Whites only appear in Europe after 1200BC with the expansion of the People of the Sea. "White" appeared in Mesopotamia represented by the Gutians.
. Click on the video below
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-------------------- C. A. Winters Posts: 13012 | From: Chicago | Registered: Jan 2006
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