Spread the word! UChicago BSD is currently searching for an instructional professor (open rank) to help develop and support graduate training in quantitative biology at UChicago. This is an Instructional Professor position (open rank). apply.interfolio.com/183517.

Thrilled to see this out. What started out as a chat several years back with @drfejzo.bsky.social about leveraging publicly available data on hyperemesis gravidarum GWAS turned into a wonderful collaboration with April Shu, @mvaudel.bsky.social, @xwww.bsky.social and many others! rdcu.be/fdl9k

Fantastic seminar from @deboraycb.bsky.social discussing some of the challenges and limitations of detecting balancing selection from genomic data and her ongoing work on developing a new ARG-based approach. See preprint here: www.biorxiv.org/content/10.6....

Getting close to a robust pipeline for ARG inference for messy genomes. 1. get a vcf. Align short reads to a reference and GATK and pray, or use whole genome assemblies and github.com/baoxingsong/... followed by github.com/RILAB/argprep

Alex Kramer, Alan Zhang and friends posted our preprint today. In it, we introduce Panmap, a tool for phylogenetic placement, assembly, lineage abundance estimation, and eDNA assignment using phylogenetic pangenomes. www.biorxiv.org/content/10.6...

We are destroying species' habitats, leading to a mass extinction event. This habitat destruction also reduces the genetic diversity _within_ species. Our latest work develops quantitative models to predict how much genetic diversity has been and _will be_ lost. 🧬🧪🧵 www.pnas.org/doi/10.1073/...

Delighted to share our latest preprint: Julie Zhu identifies a surprising reason why the genetic architecture of brain-related traits is so different than other traits. Check it out!

LongcallR for competitive SNP calling and haplotype phasing, and simplified allele-specific analysis with long RNA-seq reads. Found ~100 junctions affected by SNPs per sample with most junctions novel. Developed by Neng Huang. Published in @natmethods.nature.com. Read at rdcu.be/faKhL

Really excited that this major work from my PhD is finally published in @plosbiology.org ! In it, we were trying to tackle a fundamental question in evolution - how do genetic mutations map onto evolutionary fitness? (1/n) journals.plos.org/plosbiology/...

Why do schizophrenia GWAS signals look so flat across the genome? In our recent preprint, we explored why psychiatric disorders — and, more broadly, brain-related traits involving the central nervous system — appear to have unusual genetic architectures. 🧵1/n

Myloasm, our long-read metagenome assembler, is now published! w/ @mgmarin.bsky.social and @lh3lh3.bsky.social Very rewarding after > a year of development and countless hours thinking about assembly. Thanks to beta testers, Li lab, and reviewers who gave very helpful feedback. rdcu.be/famFj

Our new experimental evolution study across 30+ locations using the plant Arabidopsis thaliana —— we direct "see" adaptation and extinction to different climates at the genetic as it happens! Read it in Science dx.doi.org/10.1126/scie... @ucberkeleyofficial.bsky.social @hhmi-science.bsky.social

Long reads carry multiple small vars and SVs and their phasing. LongcallD is the only caller that tightly integrates germline/mosaic small/structural vars/MEIs and their phasing in a single C program. One command line to get competitive small variant calls and better SVs. Led by Yan Gao.

More on the Denisovan legacy in us: A Denisovan-derived Alu insertion in OCA2 contributes to pigmentation diversity in present-day Melanesians. More evidence (validated in melanocytes) that introgressed structural variants contributed to adaptive & phenotypic diversity 🧪🧬

📣Our paper is out! 🤩 We found that local modification of H3K9me3 using CRISPR/dCas9 at hotspots changes crossover activity, bringing us closer to targeted recombination in plants.🌱 Huge thanks to @szymanskalejman.bsky.social, Wojtek, Ania, and Karolina! www.science.org/doi/10.1126/...

NEE Focus issue on "Evolution in medicine", including a comment article from @alisonfeder.bsky.social and me.

Have you ever wondered how many archaic populations contributed DNA to modern humans? We know about Neanderthals and Denisovans, but the fossil and genetic evidence suggests a much more complex history! www.biorxiv.org/content/10.6...

This is truly gold.

I'm so dang excited for #PEQG26 I've already started my talk. Registration and poster abstract submission open through March 10.

@pratikkatte.bsky.social and I just released Lorax 🌲, a tool for interactive exploration of biobank-scale ancestral recombination graphs (ARGs). If you’ve ever wanted to scroll across the ancestries of thousands of genomes… this is for you.

Can we simulate realistic evolutionary trajectories and “replay the tape of life”? In this work, we propose a flexible, generalizable deep learning framework for modeling how the entire protein sequence evolves over time while capturing complex interactions across sites. 1/n doi.org/10.64898/202...

How does the strength of genetic drift evolve over long times? New preprint out 👇 www.biorxiv.org/content/10.6...

New preprint! with @a-solernunez.bsky.social Rethinking a textbook example of human adaptation "AMY1 copy number evolution in light of demographic history" Once population structure is accounted for, the classic starch–agriculture narrative becomes much less clear www.biorxiv.org/content/10.6...

The next BAPG has been announced! April 11 at Davis organized by the inimitable @jrossibarra.bsky.social! bapg-conference.github.io

The last chapter of my PhD is finally out !!!! In the same species, on neighboring islands, we see radically different warning colors emerge. Evolution in action: Selection-driven color variation in the aposematic strawberry poison frog, Oophaga pumilio: Current Biology www.cell.com/current-biol...

Great news for anyone using ARGs in non-model species: www.biorxiv.org/content/10.1...

We are holding our annual Rising Stars in Genetics and Genomics Postdoc Symposium on September 24-25, 2026! Please nominate postdocs who are conducting cutting edge, creative work, and are likely to be a leader in their field. Please nominate by April 30, 2026: forms.gle/85NZaxFezUk8... (1/2)

How could a simple self-replicating system emerge at the origins of life? RNA polymerase ribozymes can replicate RNA, but existing ones are so large that their self-replication seems impossible. Could they be smaller? Excited to share our latest work in @science.org on a new small polymerase. 1/n

We're also happy to see a second paper out today, led by Nicola de Maio, which develops methods to identify and account for mutation rate variation and recurrent errors. www.nature.com/articles/s41...

Fun news! @gcbias.bsky.social and I are teaching a 2-week online population genetics workshop this summer to raise money for the Center for Population Biology at UC Davis. We're trying to gauge interest -- please fill this out if you might be interested! And please share broadly!

A long time ago in a galaxy far away, there was a SARS-CoV-2 pandemic. Our paper, led by @martibartfast.bsky.social a) correcting errors in 4.5 million genomes & their phylogeny b) improving representation of the Global South in public data www.nature.com/articles/s41... (thread 1/n)

New paper! From Sam Snodgrass and @genomeofforrest.bsky.social, w/ @druncie.bsky.social, @gcbias.bsky.social, and a collaboration with Andres Moreno and @santiagogmm.bsky.social. Can we quantify the impact of humans on maize dispersal? Plant yourself in a comfy chair and lend me your ear: 1/10

Our work on understanding how common genetic variants contribute to recombination and aneuploidy risk is published!

Interested in using aDNA time-series datasets to estimate selection? Our study "Assessing Ancient DNA Sampling Strategies for Natural Selection Inference in Humans Using Allele Frequency Time Series Data" is now out in GBE! doi.org/10.1093/gbe/... @genomebiolevol.bsky.social @cegamorim.bsky.social

Pacific Biosciences Sells Short-Read Sequencing Assets to Illumina for $48.1M www.pacb.com/press_releas...

Our work on the generalizability of polygenic scores (PGS) from the @arbelharpak.bsky.social Lab is now officially out! We examine the accuracy of PGS predictions at the individual level. We make 3 observations that expose gaps in our understanding of PGS “portability.” rdcu.be/e0LAr (1/27)

The evolution of genetic drift over 50,000 generations https://www.biorxiv.org/content/10.64898/2026.01.25.701616v1

Balancing selection maintains some remarkable biological diversity, but detecting it from genomic data alone can be tricky. This may bias our view of its true prevalence. We investigated what makes balancing selection more or less detectable in genomic scans. + in thread & preprint!

General moment closure for the neutral two-locus Wright-Fisher dynamics https://www.biorxiv.org/content/10.64898/2026.01.16.700021v1

If you want to distract yourself while the world falls apart, this is a really cool paper from Amy that simultaneously solves many puzzling observations about malaria parasite genetics by positing the importance of multiple merges

Tracing the evolutionary histories of ultra-rare variants using variational dating of large ancestral recombination graphs https://www.biorxiv.org/content/10.64898/2026.01.07.698223v1

Global patterns of natural selection inferred using ancient DNA https://www.biorxiv.org/content/10.64898/2026.01.07.697984v1

Together with @ronghuizhu.bsky.social, we are thrilled to present our new perturb-seq study of 22M primary CD4+ T cells, across donors and timepoints – the result of a decade-long collaboration between the Marson @marsonlab.bsky.social and Pritchard @jkpritch.bsky.social labs 🧵 tinyurl.com/gwt2025

I'm just delighted to announce our new preprint on genome-scale perturb-seq in CD4+ T cells. We learned both general lessons about the power of perturb-seq, and specific lessons about T cell biology. Led by amazing postdocs Emma Dann and Ronghui Zhu, with my wonderful collaborator Alex Marson.

New preprint alert: we use sign errors as a test of how well TWAS works. Very worryingly we find that TWAS gets the sign wrong around 1/3 of the time (compared to 50% for pure guessing). You can read more about our analysis here, and what we think is going on 👇

How well does TWAS estimate a gene’s direction of effect on a trait? We think of this as an important stress-test for the accuracy of TWAS. In a new pre-print, we find that TWAS gets the sign wrong around 20-30% of the time! doi.org/10.64898/202... 1/n

Did you know there are 2 types of avocado varieties? A-types switch from female to male, B-types male to female, within a single day. This reciprocal sex alternation promotes cross-pollination and has a simple genetic basis. Read more in this recent preprint from the final chapter of my PhD thesis 🥑

Congrats @jeffgroh.bsky.social et al. Some avocado trees open female-phase flowers in the morning & then male in afternoon. Others show complementary pattern (m->f), to synchronize pollination of two types. Jeff show this to be a >45Mya polymorphism at a transcription factor across 100s of species.

How much better is an ancestral recombination graph (ARG) than a site frequency spectrum (SFS)? For recovering mutation rate history, we can answer fairly precisely because both ARG and SFS are linear transforms of mutation rate history. This blog post uses spectral analysis to clarify the picture.