Arjun Biddanda
aabiddanda.github.io
Arjun Biddanda
@aabiddanda.github.io
Statistical and population geneticist | Postdoc @ JHU Biology | COYS | Costco enthusiast | aabiddanda.github.io
Pinned
Thrilled to see this work out - its been fascinating to look at statistical genetics in these IVF embryo datasets underlying meiotic aneuploidies and recombination! Joint work led with @saracarioscia.bsky.social. See thread below, thoughts welcome!

www.medrxiv.org/content/10.1...
Reposted by Arjun Biddanda
First time on Bsky and first big announcement!

I am excited to announce that our new study explaining the missing heritability of many phenotypes using WGS data from ~347,000 UK Biobank participants has just been published in @Nature.

Our manuscript is here: www.nature.com/articles/s41....
Estimation and mapping of the missing heritability of human phenotypes - Nature
WGS data were used from 347,630 individuals with European ancestry in the UK Biobank to obtain high-precision estimates of coding and non-coding rare variant heritability for 34 co...
www.nature.com
November 12, 2025 at 5:57 PM
Reposted by Arjun Biddanda
I am so excited to share new work on a TE insertion that regulates iridescence in swordtails, led by fantastic grad student @nadiahaghani.bsky.social and with help from many coauthors! In a time that has been so difficult to navigate, this & other projects have kept my spirits up: shorturl.at/NE65A
Insertion of an invading retrovirus regulates a novel color trait in swordtail fish
For over a century, evolutionary biologists have been motivated to understand the mechanisms through which organisms adapt to their environments. Coloration and pigmentation are remarkably variable wi...
shorturl.at
November 12, 2025 at 8:34 PM
Reposted by Arjun Biddanda
An empirical approach to evaluating the prevalence of long-lived balancing selection in humans--and important limitations. Work by @hannahmm.bsky.social
November 11, 2025 at 7:14 PM
Reposted by Arjun Biddanda
Hidden Markov Models Detect Recombination and Ancestry of SARS-CoV-2 https://www.biorxiv.org/content/10.1101/2025.11.08.687354v1
November 11, 2025 at 2:33 AM
Reposted by Arjun Biddanda
My first preprint of my PhD! Thanks to @ekerdoncuff.bsky.social and @moorjanipriya.bsky.social for their guidance and mentorship in this project!
Revisiting the Evolution of Lactase Persistence: Insights from South Asian Genomes https://www.biorxiv.org/content/10.1101/2025.11.05.686799v1
November 7, 2025 at 12:28 AM
Reposted by Arjun Biddanda
How do GWAS and rare variant burden tests rank gene signals?

In new work @nature.com with @hakha.bsky.social, @jkpritch.bsky.social, and our wonderful coauthors we find that the key factors are what we call Specificity, Length, and Luck!

🧬🧪🧵

www.nature.com/articles/s41...
Specificity, length and luck drive gene rankings in association studies - Nature
Genetic association tests prioritize candidate genes based on different criteria.
www.nature.com
November 7, 2025 at 12:05 AM
Reposted by Arjun Biddanda
Elevated mutation near crossovers inhibits the evolution of recombination https://www.biorxiv.org/content/10.1101/2025.11.01.685904v1
November 2, 2025 at 3:32 AM
Reposted by Arjun Biddanda
New preprint from another part of my PhD! 📝👇

Some mutations arise after fertilisation 🧬, so early they can appear in both a parent’s body and their germ cells.
By analysing family trio genomes 👪, we built one of the largest catalogues of these “hidden” inherited variants yet.

tinyurl.com/mvns2ytv
Landscape of parental postzygotic mutations in >11,000 rare disease trios
Postzygotic mutations (PZMs) arising post-fertilisation, prior to primordial germ cell specification, may be subsequently inherited by both somatic and germ cells, causing somatic mosaicism in the par...
tinyurl.com
October 28, 2025 at 11:04 AM
Incredibly insightful thread!
50 years ago, King & Wilson published a foundational paper that underlies the cis-regulatory paradigm (CRP) of #DevoEvo #EvoDevo, i.e., that *almost* all morphological evolution is driven by mutations in regulatory elements, rather than proteins, and it all arose from simple misunderstanding 🧪 🧵
October 29, 2025 at 2:15 PM
Reposted by Arjun Biddanda
The Johri Lab has an open postdoc position. Please send me an email, if interested. Start date is flexible. Please do share! Thank you in advance.
October 28, 2025 at 9:31 PM
Reposted by Arjun Biddanda
Why do complex traits differ in their genetic architecture?
In our new PLOS Biology paper, we will try to convince you that two simple scaling laws drive differences in the number, effect sizes and frequencies of causal variants affecting complex traits.

Thread:
journals.plos.org/plosbiology/...
Simple scaling laws control the genetic architectures of human complex traits
Genome-wide association studies have revealed that the genetic architectures of complex traits vary widely. This study shows that differences in architectures of highly polygenic traits arise mainly f...
journals.plos.org
October 24, 2025 at 1:51 AM
Reposted by Arjun Biddanda
Hey Yaniv Brandvain is not on Bluesky but his most recent biostats ebook is live ybrandvain.github.io/biostats/. His stats resources have been so helpful to me as I develop my own stats course, so check it out. Github repo here: github.com/ybrandvain/b...
Applied Biostatistics
ybrandvain.github.io
October 24, 2025 at 2:47 PM
Reposted by Arjun Biddanda
One of the most exciting works of my career, years in the making. We used high-throughput precision genome editing to test the fitness effects of thousands of natural variants. Our findings challenge the long-held assumption that common variants are inconsequential.

www.biorxiv.org/content/10.1...
Massively parallel interrogation of the fitness of natural variants in ancient signaling pathways reveals pervasive local adaptation
The nature of standing genetic variation remains a central debate in population genetics, with differing perspectives on whether common variants are almost always neutral as suggested by neutral and n...
www.biorxiv.org
October 22, 2025 at 5:46 PM
Reposted by Arjun Biddanda
If you need more exciting news about Denisovans, check out our paper on Denisovan ancestry in modern humans through time, out today in Current Biology: www.cell.com/current-biol...! #Denisovan #ancientDNA
An early East Asian lineage with unexpectedly low Denisovan ancestry
Yang et al. study Denisovan ancestry in ancient and present-day humans. In contrast to other East Asians, genomic comparisons suggest that the Jomon derived most of their ancestry from a deep lineage…
www.cell.com
October 20, 2025 at 6:14 PM
Reposted by Arjun Biddanda
We're excited to be recruiting an NIH funded postdoc to work in the Coop lab at UC Davis. We're specifically interested in candidates who are want to work at the intersection of human genetics, GWAS, and population genetics modeling. Please RT
October 15, 2025 at 3:53 PM
Great to be back at #ASHG25 this year 👋 I'm excited to present some follow-up work on using PGT data to design tests for transmission distortion on Thursday. Poster 3058T 🧬
October 15, 2025 at 10:57 AM
Reposted by Arjun Biddanda
Our paper on clonal expansions in Sperm is out in Nature www.nature.com/articles/s41...
If you are interested in working at an intersection of Mendelian genomics/Population genetics/Clonal expansions +Cancer genetics/ and of course mutagenesis, please rich out about postdoc in my lab
October 8, 2025 at 4:52 PM
Reposted by Arjun Biddanda
Now published! Our paper on:
(1) Accurate sequencing of sperm at scale
(2) Positive selection of spermatogenesis driver mutations across the exome
(3) Offspring disease risks from male reproductive aging
[1/n]
www.nature.com/articles/s41...
Sperm sequencing reveals extensive positive selection in the male germline - Nature
A combination of whole-genome NanoSeq with deep whole-exome and targeted NanoSeq is used to accurately characterize mutation rates and genes under positive selection in sperm cells.
www.nature.com
October 8, 2025 at 3:51 PM
Reposted by Arjun Biddanda
Delighted that our paper about the distribution of genomic spans of clades/edges in genealogies (ARGs), and using this for detecting inversions and other SVs (and other phenomena that cause local disruption of recombination) is out in MBE academic.oup.com/mbe/article/... (1/n)
The Length of Haplotype Blocks and Signals of Structural Variation in Reconstructed Genealogies
Abstract. Recent breakthroughs have enabled the accurate inference of large-scale genealogies. Through modelling the impact of recombination on the correla
academic.oup.com
October 3, 2025 at 9:54 AM
Reposted by Arjun Biddanda
Pleased to have contributed to this paper out at @nature.com today from @vw1234.bsky.social and Yira (Xinhe) Zhang showing that the common variant contribution to autism varies substantially by age of diagnosis www.nature.com/articles/s41.... Critical for understanding heterogeneity in autism.
Polygenic and developmental profiles of autism differ by age at diagnosis - Nature
A study of several longitudinal birth cohorts and cross-sectional cohorts finds only moderate overlap in genetic variants between autism that is diagnosed earlier and that diagnosed later, so they may represent aetiologically different conditions.
www.nature.com
October 2, 2025 at 2:46 PM
Reposted by Arjun Biddanda
🚨 First pre-print from my team !!

TL;DR: presence of polymorphism (sequence differences between the homologous chromosomes) can *increase* the local rate of recombination in Arabidopsis thaliana, turning cold regions of the genome hot (purple v. grey) !
October 1, 2025 at 8:31 AM
Reposted by Arjun Biddanda
🚨 New preprint out!
We reconstructed parental haplotypes in >440k individuals (UK & Estonian biobanks) to estimate assortative mating directly in the parental generation.
This reveals intensified assortment in recent generations.
www.biorxiv.org/content/10.1...
September 26, 2025 at 5:10 PM
Reposted by Arjun Biddanda
C. elegans is a real animal and we set out to understand how it comes to have its distinctive biogeography. Its ancestral center of diversity is in the higher elevation forests of Hawaii. Its closest relatives are spread across east Asia. Did they travel from Asia? [Preprint 🧵]
September 24, 2025 at 8:33 PM
Reposted by Arjun Biddanda
Our paper about how ancestral recombination graphs can be used to detect "phantom" genetic interaction signals (that arise due to the genealogy, rather than "real" epistasis) is out in Genetics! Nice thread here by @linoafferreira.bsky.social

academic.oup.com/genetics/adv...
September 15, 2025 at 10:33 AM
Reposted by Arjun Biddanda
I'm hiring a computational biologist interested in complex trait genetics using deep learning approaches. Reach out to me, if interested.
September 12, 2025 at 7:00 PM