A unified genealogy of modern and ancient genomes

Angela

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"A unified genealogy of modern and ancientgenomes"

Anthony Wilder Wohns1,2,*, Yan Wong1, Ben Jeffery1, AliAkbari2,3,6, Swapan Mallick2,4, Ron Pinhasi5, Nick Patterson2,3,4,6,David Reich2,3,4,6, Jerome Kelleher1,+, and Gil McVean

https://www.biorxiv.org/content/10.1101/2021.02.16.431497v1.full.pdf

All the big labs got together for this. So far, the analysis doesn't change the big picture, but there "are" changes.

"The sequencing of modern and ancient genomes from around the world hasrevolutionised our understanding of human history and evolution1,2. However,the general problem of how best to characterise the full complexity of ancestralrelationships from the totality of human genomic variation remains unsolved.Patterns of variation in each data set are typically analysed independently, andoften using parametric models or data reduction techniques that cannot capture the full complexity of human ancestry3,4. Moreover, variation in sequencingtechnology5,6, data quality7 and in silico processing8,9, coupled with complexities of data scale10, limit the ability to integrate data sources. Here, we introducea non-parametric approach to inferring human genealogical history that overcomes many of these challenges and enables us to build the largest genealogyof both modern and ancient humans yet constructed. The genealogy providesa lossless and compact representation of multiple datasets, addresses the challenges of missing and erroneous data, and benefits from using ancient samplesto constrain and date relationships. Using simulations and empirical analyses,we demonstrate the power of the method to recover relationships between individuals and populations, as well as to identify descendants of ancient samples.Finally, we show how applying a simple nonparametric estimator of ancestor geographical location to the inferred genealogy recapitulates key events in humanhistory. Our results demonstrate that whole-genome genealogies are a powerful means of synthesising genetic data and provide rich insights into humanevolution."

The real meat is going to be in the Supplements, but here is one nugget: the paper includes four new high coverage genomes from Afanasievo.

"For the Afanasievo family, we find the greatest amount of descent from theirproxy ancestral haplotypes among individuals in Western Eurasia and SouthAsia (Extended Data Fig. 6a), consistent with findings from the geneticallysimilar Yamnaya peoples36. Notably, the most frequent descendant blocks inExtended Data Fig. 6b all contain geographically disparate modern samples.These cosmopolitan patterns of descent support a contemporaneous diffusion ofAfanasievo-like genetic material via multiple routes36."
 
You should go to page 30-31. The highest percentage of ancestry from the Afanasievo family on Chromosome 20 for West Eurasians is one of the French samples, then another French sample, then Jordanian, Adyghe, Great Britain. The greatest percentage overall is with Pathans but not by a lot and the other South Asians are much lower. (The Jordanians are the only Middle Easterners at that high level. So, a fluke on that chromosome?)

What's on Chromosome 20 generally, btw?

There's also a nice graph for Neanderthal ancestry. East Asians definitely have more. (For that one it's Chromosomes 17-22.
 
Angela: Thanks for the notice of this paper. The Neanderthal admixture graph was very good. I also I found Figure 4 really interesting.
 
Exciting time to be around with the revolutions in biology, the new techniques being pioneered. Are common heritage.
Amazing, they are able to track all the little common segments of shared shuffled ancestry, between West Asian, East Asian, South Asian, Neanderthal, Denisovan,(unknown 3rd?) Interesting it will be, to see if AI in the future is applied to parse the sequences to form a possible migration path between ancient samples(introgression event -time, and geography-- between Homo Sapiens Sapiens-Homo Sapien Neaderthal-Homo Sapien Denisovan-Homo Sapien 3rd unknown?).

I always liked the old school, Karl Landsteiner> A.E Mourant>Dr. Cavalli-Sforza.
Billions of replications yet the same basic stable evolutionary groups.
 
Image:

Total length of Afanasievo-like Ancestry - Genomic Descent from Afanasievo-like Ancestry:

JhhxMjy.jpg
 
You should go to page 30-31. The highest percentage of ancestry from the Afanasievo family on Chromosome 20 for West Eurasians is one of the French samples, then another French sample, then Jordanian, Adyghe, Great Britain. The greatest percentage overall is with Pathans but not by a lot and the other South Asians are much lower. (The Jordanians are the only Middle Easterners at that high level. So, a fluke on that chromosome?)

What's on Chromosome 20 generally, btw?

There's also a nice graph for Neanderthal ancestry. East Asians definitely have more. (For that one it's Chromosomes 17-22.

... maybe they just picked a representative Chromosome to simplify the explanation of their findings, I think :)

... “In this study, we illustrate our approach using Chromosome 20” ...

I do the same thing with a segment of my chrom. 8 on MTA because it carries 40+ samples representing the bulk of contiguous relationships among the ancient samples.
 
You should go to page 30-31. The highest percentage of ancestry from the Afanasievo family on Chromosome 20 for West Eurasians is one of the French samples, then another French sample, then Jordanian, Adyghe, Great Britain. The greatest percentage overall is with Pathans but not by a lot and the other South Asians are much lower. (The Jordanians are the only Middle Easterners at that high level. So, a fluke on that chromosome?)

What's on Chromosome 20 generally, btw?

There's also a nice graph for Neanderthal ancestry. East Asians definitely have more. (For that one it's Chromosomes 17-22.

If other south asians are much lower, does it mean that their steppe admixture is not related with yamna's steppe admixture? I think karash people has 50% steppe admixture.
 
If other south asians are much lower, does it mean that their steppe admixture is not related with yamna's steppe admixture? I think karash people has 50% steppe admixture.

Not at all; it just means that India was densely populated and the steppe " percentages get lower and lower the further into India you go and the lower you go on the caste pyramid.

What I have found interesting is that, if I remember correctly, the Brahmins have less steppe ancestry on average than the warrior caste, the Kshatriyas.

Also, the Kalash are in this paper, and they don't have all that much. So much for they were a lost tribe of steppe people if the paper is correct.

It's only as you go further north that you get significant amounts of steppe, imo. Many of those "predictions" by Eurogenes about the amount of steppe ancestry which would be found in India were just wishful thinking.
 

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