mtDNA, lactase persistence, and admixr for ADMIXTOOLS

lactase-persistence-timing-geography

The following are some recent developments and updates:

I. Ancient DNA Dataset version 2

I.1. Accurate mtDNA haplogroups

I was meaning to update the mtDNA part of the Ancient DNA Dataset, and finally found some time to review FTDNA and YFull nomenclature (including hyperlinks), as well as those SNP calls from published samples found in YFull’s MTree. So, if you are interested in studies of mtDNA phylogeography, I think the data is now accurate and much more useful.

Given the number of columns and the size of the files, I have decided to post shorter standard versions, by … Read the rest “mtDNA, lactase persistence, and admixr for ADMIXTOOLS”

Online GIS maps of ancient Y-DNA, mtDNA and ADMIXTURE

arcgis-online-y-dna

The last few weeks have been very exciting in terms the amount, diversity and quality of newly reported ancient samples, which included new genotypes and also Y-DNA and mtDNA haplogroups.

As some of you already know, I had been preparing a tailored GIS map of ancient DNA using QGIS-server on Ubuntu and trying some of the available plugins for the task, and was ready to use my old broken PC as a web server. For that, I needed to prepare different files corresponding to the different conventional divisions of the Prehistory Atlas. The crazy number of recently reported papers … Read the rest “Online GIS maps of ancient Y-DNA, mtDNA and ADMIXTURE”

Ancient phylogeography: spread of haplogroups R1b, R1a and N

haplogroups-r1a-r1b-q

The previous post showed the potential use of TreeToM to visualize ancient DNA samples in maps together with their Y-DNA phylogenetic trees. I have written Newick trees for Y-chromosome haplogroups R1b-L388 (encompassing R-V1636 and R-P297, which in turn split into R-M73 and R-M269), R1a, and N.

I have reviewed some of the BAM files from my previous bulk analyses with YLeaf v.2, to add information that I had not previously included in the All Ancient DNA Dataset, and which might be relevant to the proper depiction of phylogenetic trees; in particular, positive and negative SNPs potentially distinguishing archaicRead the rest “Ancient phylogeography: spread of haplogroups R1b, R1a and N”

A Game of Thrones in Indo-European: proto-languages in Westeros and Essos, and population genomics

game-of-thrones-westeros-essos-map

I think proto-languages can be applied to basically any appropriate prehistoric setting, and especially to science fiction and fantasy settings. I often viewed the lack of interest for them as based on the idea that they are not fantastic enough, that they would render a fantastic world too realistic to allow for an adequate immersion of the reader (or viewer) into a new world.

With time, I have become more and more convinced that most authors don’t use proto-languages (or tweaked versions of them) simply because they can’t, and resort to the easier way: inventing some rules … Read the rest “A Game of Thrones in Indo-European: proto-languages in Westeros and Essos, and population genomics”

Genetic landscapes showing human genetic diversity aligning with geography

world-effective-migration

New preprint at BioRxiv, Genetic landscapes reveal how human genetic diversity aligns with geography, by Peter, Petkova, and Novembre (2017).

Abstract:

Summarizing spatial patterns in human genetic diversity to understand population history has been a persistent goal for human geneticists. Here, we use a recently developed spatially explicit method to estimate “effective migration” surfaces to visualize how human genetic diversity is geographically structured (the EEMS method). The resulting surfaces are “rugged”, which indicates the relationship between genetic and geographic distance is heterogenous and distorted as a rule. Most prominently, topographic and marine features regularly align with increased genetic

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Effective migration in Western Eurasia reveals fine-scale migration surface features

map-effective-migration-eurasia

Interesting poster from SMBE 2017, Maps of effective migration as a summary of global human genetic diversity, by Benjamin Peter, Desislava Petkova, Matthew Stephens & John Novembre, of the JNPopGen group of the University of Chicago.

You can read the full poster in the original PDF, or in compressed image. The following are important excerpts:

Aim: To answer the following questions:

  • Which regions have high/low effective migration?
  • How well is human genetic diversity explained by this pure isolation-by-distance model?
  • How does the explanatory performance of EEMS compare to PCA?

Method: It uses the

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