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Gnads
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Brian Ross wrote on Jul 4 th, 2020 at 8:49pm: Gnads wrote on Jul 4 th, 2020 at 7:42pm: Brian Ross wrote on Jul 2 nd, 2020 at 8:10pm: Gnads wrote on Jul 2 nd, 2020 at 7:10pm: Brian Ross wrote on Jul 2 nd, 2020 at 11:55am: Yep that's what you've got ........ nothing. Typed by a man who believes in outmoded, 19th century theories about "race". Tsk, tsk. Genetics aren't outmoded because some wanker progressive wants to rewrite science to suit his/her dreams. The physical differences between racial groups is caused by genetic selection not social constructs.(more wank words) You're throwing out all of Darwins theory of natural selection & genetics ...... why? Because you're a feckin eyjut. Theories are not facts, Gnads. Genetics has proven there is no such thing as "race" as you use the term. Indeed, as Darwin used the term. Humans are one genome, not several. Get used to it, that Black man could be your brother, or you cousin or your uncle... We are not just made up of a single genome...... all groups have genetic variations as does each individual...... DNA. Quote:RESULTS We identified 67.3 million single-nucleotide polymorphisms, 8.8 million small insertions or deletions (indels), and 40,736 copy number variants. This includes hundreds of thousands of variants that had not been discovered by previous sequencing efforts, but which are common in one or more population. We demonstrate benefits to the study of population relationships of genome sequences over ascertained array genotypes, particularly when involving African populations.
Populations in central and southern Africa, the Americas, and Oceania each harbor tens to hundreds of thousands of private, common genetic variants. Most of these variants arose as new mutations rather than through archaic introgression, except in Oceanian populations, where many private variants derive from Denisovan admixture. Although some reach high frequencies, no variants are fixed between major geographical regions.
We estimate that the genetic separation between present-day human populations occurred mostly within the past 250,000 years. However, these early separations were gradual in nature and shaped by protracted gene flow. All populations thus still had some genetic contact more recently than this, but there is also evidence that a small fraction of present-day structure might be hundreds of thousands of years older. Most populations expanded in size over the past 10,000 years, but hunter-gatherer groups did not.
The low diversity among the Neanderthal haplotypes segregating in present-day populations indicates that, while more than one Neanderthal individual must have contributed genetic material to modern humans, there was likely only one major episode of admixture. By contrast, Denisovan haplotype diversity reflects a more complex history involving more than one episode of admixture.
We found small amounts of Neanderthal ancestry in West African genomes, most likely reflecting Eurasian admixture. Despite their very low levels or absence of archaic ancestry, African populations share many Neanderthal and Denisovan variants that are absent from Eurasia, reflecting how a larger proportion of the ancestral human variation has been maintained in Africa.
CONCLUSION The discovery of substantial amounts of common genetic variation that was previously undocumented and is geographically restricted highlights the continued value of anthropologically informed study designs for understanding human diversity. The genome sequences presented here are a freely available resource with relevance to population history, medical genetics, anthropology, and linguistics.
Structure of genetic variation across worldwide human populations. Shown is a schematic illustration of the approximate amounts of four different classes of genetic variation found in different geographical regions. The origins of the populations included in the study are indicated by dots.
Abstract Genome sequences from diverse human groups are needed to understand the structure of genetic variation in our species and the history of, and relationships between, different populations. We present 929 high-coverage genome sequences from 54 diverse human populations, 26 of which are physically phased using linked-read sequencing. Analyses of these genomes reveal an excess of previously undocumented common genetic variation private to southern Africa, central Africa, Oceania, and the Americas, but an absence of such variants fixed between major geographical regions. We also find deep and gradual population separations within Africa, contrasting population size histories between hunter-gatherer and agriculturalist groups in the past 10,000 years, and a contrast between single Neanderthal but multiple Denisovan source populations contributing to present-day human populations.
http://www.sciencemag.org/about/science-licenses-journal-article-reuse https://science.sciencemag.org/content/367/6484/eaay5012Genetics does not rule out human groups(racial) variation/difference. It proves it. Vive la difference.
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