Ancient uniparental DNAs in distinguishing the competing theories of molecular evolution and modern human origins

Abstract Analyses of extant people have resulted in two models for the uniparental DNA phylogenetic trees of modern humans rooted in either Africa or East Asia. The Africa model is based on the neutral theory. The Asia model is reached from the maximum genetic diversity (MGD) theory. To test the two competing theories, we examined published data of ancient uniparental DNAs. Many ancient samples belonging to a terminal haplogroup were found to have mutated only in some, but not all, of the sites that define a more basal haplogroup. This pattern was found for the non-controversial haplogroups shared by the two competing models, and also for the haplogroups specific to the Asia model. Furthermore, many ancient samples that do not belong to some of the haplogroups of the Africa model nonetheless had mutations in them, which makes it impossible to unambiguously assign them to a haplogroup within the Africa model. Finally, uniparental DNAs of archaic humans were found to carry some modern alleles present in the first uniparental DNAs in the Asia model, indicating convergent evolution. Therefore, the data from ancient DNAs have verified the MGD theory and the actual existence of the haplogroups specific to the Asia model.

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Humans: DNA comparison of Africa's ethnic groups quantifies genetic diversity: Differences could reveal details of modern human origins

Science News ◽

10.1002/scin.2009.5591751109 ◽

2009 ◽

Vol 175 (11) ◽

pp. 10-10

Author(s):

Solmaz Barazesh

Keyword(s):

Genetic Diversity ◽

Ethnic Groups ◽

Modern Human ◽

Human Origins ◽

Modern Human Origins

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Modern human origins: multiregional evolution of autosomes and East Asia origin of Y and mtDNA

10.1101/101410 ◽

2017 ◽

Cited By ~ 9

Author(s):

Dejian Yuan ◽

Xiaoyun Lei ◽

Yuanyuan Gui ◽

Mingrui Wang ◽

Ye Zhang ◽

...

Keyword(s):

East Asia ◽

Molecular Model ◽

Explanatory Power ◽

Neutral Theory ◽

Modern Human ◽

Human Populations ◽

Human Origins ◽

Modern Human Origins ◽

Southern Chinese ◽

Public Data

AbstractThe neutral theory has been used as a null model for interpreting nature and produced the Recent Out of Africa model of anatomically modern humans. Recent studies, however, have established that genetic diversities are mostly at maximum saturation levels maintained by selection, therefore challenging the explanatory power of the neutral theory and rendering the present molecular model of human origins untenable. Using improved methods and public data, we have revisited human evolution and found sharing of genetic variations among racial groups to be largely a result of parallel mutations rather than recent common ancestry and admixture as commonly assumed. We derived an age of 1.86-1.92 million years for the first split in modern human populations based on autosomal diversity data. We found evidence of modern Y and mtDNA originating in East Asia and dispersing via hybridization with archaic humans. Analyses of autosomes, Y and mtDNA all suggest that Denisovan and Neanderthal were archaic Africans with Eurasian admixtures and ancestors of South Asia Negritos and Aboriginal Australians. Verifying our model, we found more ancestry of Southern Chinese from Hunan in Africans relative to other East Asian groups examined. These results suggest multiregional evolution of autosomes and replacements of archaic Y and mtDNA by modern ones originating in East Asia, thereby leading to a coherent account of modern human origins.

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