Author Archives: Arun Sethuraman

About Arun Sethuraman

I am a computational biologist, and I build statistical models and tools for population genetics. I am particularly interested in studying the dynamics of structured populations, genetic admixture, and ancestral demography.

Unbalanced population sampling and STRUCTURE

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

Divergence and Linked Background Selection

We have widely discussed the reduction in neutral diversity due to demography and linked selection effects (e.g. selective sweeps and hitchhiking, or background selection) in several previous posts (e.g see here, here, and here). However, how linked selection affects neutral divergence … Continue reading

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On (mis)interpreting STRUCTURE/ADMIXTURE results

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

Live from #Evol2016 – highlights from Sunday and what to see on Monday June 20th

Day two was just as eventful – lots of exciting talks, getting some in-between-talk-fitness in sprinting through the aisles (only to be wrecked by deep fried macaroni and cheese balls at the poster session), and schmoozing with the who’s who in … Continue reading

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The Great Migration and African-American Genomic History

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

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

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What does the island fox say?

Small populations are characterized by large drift and reduced efficacy of selection effects, which result in fixation of both advantageous and deleterious alleles, accumulation of homozygosity, and often reduction in population fitness. What with plummeting mammal populations across biota, understanding … Continue reading

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