Tag Archives: population structure

Unbalanced population sampling and STRUCTURE

Posted on 5 Jan, 2017 by Arun Sethuraman

The utility and intuition offered by the program STRUCTURE, and more generally, the ‘admixture’ model of Pritchard et al. (2000) are unquestioned – with tens of thousands of citations, it retains its lead among the most popular population genetics software. … Continue reading →

Posted in bioinformatics, genomics, howto, methods, population genetics, software, STRUCTURE | Tagged , , | 1 Comment

On (mis)interpreting STRUCTURE/ADMIXTURE results

Posted on 5 Aug, 2016 by Arun Sethuraman

STRUCTURE, ADMIXTURE and other similar software are among the most cited programs in modern population genomics. They are algorithms that estimate allele frequencies and admixture proportions under the premise that sampled genotypes are derived from one of “K” ancestral populations, … Continue reading →

Posted in bioinformatics, genomics, howto, methods, population genetics, software, STRUCTURE | Tagged , , , , | 1 Comment

The Great Migration and African-American Genomic History

Posted on 1 Jun, 2016 by Arun Sethuraman

Over 45 million African-Americans share a recent common history largely shaped by “The Great Migration” (1910-1970) from out of the Southern United States. And yet, the admixture history of the African-American community, and its consequences for public health are little … Continue reading →

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Ice-Age Euro-trips

Posted on 19 May, 2016 by Arun Sethuraman

Recent works that attempt to get at human migrations inside Europe paint a complex portrait of migratory events, admixture with archaic hominids, and adaptive evolution to new geographies, and a changing global climate. Analyzing whole genomes of 51 ancient humans … Continue reading →

Posted in adaptation, evolution, genomics, natural history, Paleogenomics, population genetics, selection | Tagged , , , , , , , , | Leave a comment

Opening Pandora's box: PSMC and population structure

Posted on 18 May, 2016 by Patrícia Chrzanová Pečnerová

Essentially, all models are wrong, but some are useful. — George Box Publication of the Li and Durbin’s 2011 paper titled “Inference of human population history from individual whole-genome sequences” was a milestone in the inference of demography. By allowing … Continue reading →

Posted in bioinformatics, methods, Paleogenomics, population genetics, theory | Tagged , , , , | 6 Comments

Finding hidden structure in uneven data

Posted on 23 Feb, 2016 by Rob Denton

If you are a population geneticist, your work might include sampling a bunch of individuals and figuring out who is related to who. Seems simple right? Before you can ask questions about differences or similarities between groups, you have to understand what … Continue reading →

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Genomics of Hybridization – Part II, Top three of 2015

Posted on 28 Jan, 2016 by Arun Sethuraman

Death Valley pupfishes (Cyprinodon) are among the most endangered vertebrates on earth, with small inbred populations, with heavy risks of extinction in extreme environments. Martin et al. (2016) in a recent publication quantify diversity and adaptability in a very small population … Continue reading →

Posted in bioinformatics, conservation, genomics, methods, natural history, next generation sequencing, population genetics, R, software, speciation, STRUCTURE, theory | Tagged , , , , | Leave a comment

Genomics of Hybridization – Part 1

Posted on 21 Jan, 2016 by Arun Sethuraman

In a series of articles, I will discuss recent advances in hybridization genomics – the fundamentals of adaptive introgression, “islands of speciation”, differential gene flow, and linked selection have been discussed in my previous posts (here, here, and also at … Continue reading →

Posted in adaptation, evolution, genomics, methods, natural history, next generation sequencing, pedigree, phylogenetics, plants, population genetics, RNAseq, software, speciation, species delimitation, STRUCTURE, theory, transcriptomics | Tagged , , , , , , | Leave a comment

Earthquakes and rapid evolution

Posted on 7 Jan, 2016 by Arun Sethuraman

The 1964 Alaskan earthquake was landscape-altering in creating/uplifting numerous islands in the Gulf of Alaska, providing an ideal system to study adaptive evolution of diversification in affected species – the threespine stickleback (Gasterosteus aculeatus) being a widely studied example. In … Continue reading →

Posted in adaptation, evolution, genomics, natural history, next generation sequencing, phylogeography, population genetics, selection, STRUCTURE | Tagged , , , , , , | Leave a comment

Long distance dispersal of modern humans outside of Africa

Posted on 10 Dec, 2015 by Arun Sethuraman

Long distance dispersal (LDD) has long known to be an artifact of human migrations out of Africa. However, the effects of LDD on modern human diversity, and models of LDD in human colonization are yet to be characterized. Using an … Continue reading →

Posted in evolution, genomics, natural history, population genetics | Tagged , , , , , | 2 Comments