Published August 13, 2025 | https://doi.org/10.59350/stephenturner.166139640

Weekly Recap (Aug 2025, part 3)

Creators & Contributors

  • 1. ROR icon University of Virginia
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This week's recap highlights analysis of human de novo mutation rates from a four-generation pedigree reference, how LLMs internalize scientific literature and citation practices, the py_ped_sim forward pedigree and genetic simulator for complex family pedigree analysis, and a review on predicting gene expression from DNA sequence using deep learning models like Enformer and Borzoi.

Others that caught my attention include the GeneChat multimodal LLM for gene function prediction, the Ish tool for accelerated local and semi-global alignment, improving gene isoform quantification with miniQuant, the TreeHub comprehensive dataset of phylogenetic trees, a new diversity index for multispecies analysis, performance of deep learning-based approaches to improve polygenic scores, genome and epigenome engineering for improving loss-of-function genetic screening approaches, polygenic scores in ancient samples, a self-hosted literature review utility and claim verification tool using LLMs, and the BioReason model that integrates reasoning LLMs with DNA foundation models.

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Deep dive

  1. Human de novo mutation rates from a four-generation pedigree reference

  2. How Deep Do Large Language Models Internalize Scientific Literature and Citation Practices?

  3. py_ped_sim: a flexible forward pedigree and genetic simulator for complex family pedigree analysis

  4. Predicting gene expression from DNA sequence using deep learning models

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Human de novo mutation rates from a four-generation pedigree reference

Paper: Porubsky, D., et al, "Human de novo mutation rates from a four-generation pedigree reference", Nature, 2025. https://doi.org/10.1038/s41586-025-08922-2.

This study provides one of the most complete pictures of human de novo mutations by generating near-T2T genome assemblies for an entire four-generation family.

TLDR: Instead of just mapping reads to a standard reference, the authors directly compared parental and offspring assemblies, allowing them to accurately identify all types of mutations, even in the trickiest, most repetitive parts of the genome. This work reveals that tandem repeats are a major source of new mutations and that our overall mutation rate is higher than previously thought, offering a foundational "truth set" for human genetics.

Summary: By applying five complementary short- and long-read sequencing technologies to a 28-member, four-generation pedigree (CEPH 1463), this study produced highly contiguous and phased diploid genome assemblies for each individual. This assembly-based approach circumvents the limitations of mapping to a single reference genome, enabling a comprehensive analysis of de novo mutations (DNMs) across the entire genome, including previously intractable regions like centromeres, segmental duplications, and the Y chromosome. The work provides a much more detailed view of the mutational landscape, estimating 98-206 DNMs per transmission and confirming a strong paternal bias (75-81%) for most variant types. A key finding is the extreme mutability of tandem repeats, which are now shown to be a major contributor to new genetic variation. The resulting high-resolution variation and recombination maps serve as a critical benchmark resource for the genomics community, refining our understanding of the fundamental processes that generate human diversity and providing a gold standard for evaluating future sequencing technologies and bioinformatic tools.

Methodological highlights

  • A multi-platform approach was used, combining PacBio HiFi, ultra-long ONT, Strand-seq, Illumina, and Element sequencing to assemble and phase genomes, which overcomes the biases and error profiles of any single technology.

  • Direct comparison of parent-offspring assemblies, rather than mapping to a reference, was used to discover DNMs, which dramatically improved sensitivity for all variant classes, especially structural variants and mutations in repetitive DNA.

  • A new tool, TRGT-denovo, was developed to specifically identify de novo tandem repeat mutations from HiFi data, with subsequent validation using orthogonal Element sequencing and pedigree-based transmission analysis to ensure high accuracy.

New tools, data, and resources

Fig. 1
Figure 1 from Porubsky 2025: Sequencing the CEPH 1463 pedigree with five technologies. Twenty-eight members of the four-generation pedigree CEPH 1463 were sequenced using five orthogonal next-generation and LRS platforms: HiFi sequencing, Illumina and Element sequencing were performed on peripheral blood for G2–G4, and UL-ONT and Strand-seq data were generated on available lymphoblastoid cell lines for G1–G3. The pedigree dataset has been expanded to include the fourth generation and G3 spouses (200080 and 200100).

How Deep Do Large Language Models Internalize Scientific Literature and Citation Practices?

Paper: Algaba A., et al, "How Deep Do Large Language Models Internalize Scientific Literature and Citation Practices?" arXiv (2025), DOI: 10.48550/arXiv.2504.02767.

Large-language-model citation suggestions aren't neutral; they strongly favor already-famous, recent papers.

TL;DR: The authors analyzed 274 k GPT-4o-generated references for 10k papers and show that these suggestions amplify the "Matthew effect" and other human-like biases, which matters because automated assistants are creeping into every literature search workflow.

Summary: This study prompted GPT-4o with only title, author list, venue and abstract for 10 000 papers sampled from the SciSciNet database and asked it to "write the reference list." The 274 951 suggestions were matched, where possible, to real publications and benchmarked against the papers' actual references. Systematic patterns emerged: generated lists overwhelmingly picked highly-cited, high-impact-journal articles with short titles and small author teams, and roughly half of the suggestions were hallucinations. Despite these biases, semantic-embedding and network-structure analyses showed the AI-proposed references remain topically well-aligned and form citation graphs eerily similar to human ones. The work highlights both promise and risk: LLMs can accelerate literature triage, but unchecked they could entrench citation inequalities, steer discovery toward already dominant ideas, and skew research assessment frameworks.

Methodological highlights

  • Sampled 10,000 "Q1-journal" papers (1999-2021) across 18 fields from SciSciNet and elicited GPT-4o reference lists mirroring each paper's ground-truth reference count.

  • Matched 274 k generated references to the database with fuzzy title-/author-string alignment; classified matches vs. hallucinations and benchmarked citation counts using Wilcoxon signed-rank tests.

  • Compared semantic relevance (OpenAI & SPECTER2 embeddings) and local citation-network metrics, revealing AI-generated graphs that replicate human structures yet intensify high-citation clustering.

New tools, data, and resources

Refer to caption
Figure 1 from Algaba 2025: Overview of the experiment comparing the characteristics of human citations and LLM generated references, when tasked to suggest references based on the title, authors, year, venue, and abstract of a paper.

py_ped_sim: a flexible forward pedigree and genetic simulator for complex family pedigree analysis

Paper: Guardado M., et al, "py_ped_sim: a flexible forward pedigree and genetic simulator for complex family pedigree analysis" BMC Bioinformatics (2025), https://doi.org/10.1186/s12859-025-06142-z.

Back when I worked in the forensic genomics space I used ped-sim from Amy Williams' lab for the simulations used in several papers on kinship analysis. py_ped_sim looks like a nice alternative.

TL;DR: py_ped_sim lets you spin up realistic pedigrees and their genomes from the same Python command line, which is perfect for testing kinship, medical-genetics, and forensic pipelines. The tool models variable sibship sizes, misattributed paternity, and genome evolution through a SLiM wrapper, then the authors show on 10,000 simulated families that kinship coefficients and IBD patterns line up with theory. That validation makes it a handy drop-in for any workflow that needs synthetic but believable pedigree data.

Summary: The paper introduces a forward-time simulator that treats pedigrees as directed acyclic graphs and can vary sibship distributions across generations, insert misattributed-paternity events, and broaden families horizontally before passing the structure to SLiM for genome evolution. Benchmarks on 10,000 five-generation pedigrees demonstrate that simulated kinship values for relationships from parent–child to second cousins closely match expectations, and runtime stays manageable (three hours for a 10 Mb genome on a pedigree of 3,811 individuals). This package should streamline benchmarking of relationship inference, kinship estimation, and investigative genetic genealogy software, and it can also stress-test disease-gene mapping or demographic-history methods that rely on family data.

Methodological highlights

  • Pedigree generator draws sibship sizes from user-supplied distributions (default IPUMS census data) and can vary them by generation, enabling realistic demographic shifts.

  • Optional misattributed-paternity module introduces half-relationships and consanguinity, controlled by user-set probabilities.

  • SLiM wrapper auto-detects founders and generation indices, producing VCFs whose kinship estimates (KING, hierfstat) align with theoretical values across 2,000-plus simulated relatives.

New tools, data, and resources

Figure 1 from Guardado 2025: Primary features of the py_ped_sim software. Our software comes with the ability to (Pedigree Simulations, 1) simulate pedigrees with non-uniform sibship sizes, (Misattributed Paternity, 2) simulate events of MAP onto existing pedigree structures, (Family Broadening, 3) simulate family broadening, extending the horizontal breadth of the family, (Genome Simulations, 4) simulate genomes onto pedigrees using SLiM, (Relationship Identifier, 5) identify all genetic relationships within the family pedigree

Review: Predicting gene expression from DNA sequence using deep learning models

Paper: Barbadilla-Martínez L., et al, "Predicting gene expression from DNA sequence using deep learning models" Nature Reviews Genetics (2025), https://doi.org/10.1038/s41576-025-00841-2 (read free: https://rdcu.be/elSrE).

TL;DR: This review walks through the current generation of sequence-to-expression (S2E) deep-learning models and explains how they've moved from 1,000-base convolutional nets to 500-kilobase transformer hybrids. It also pinpoints where those models still stumble (long-range enhancer logic, cell-type specificity, and variant directionality) and why that matters for anyone using AI to prioritize non-coding disease variants.

Summary: The authors synthesize nearly a decade of work on predicting gene activity directly from DNA, comparing CNN approaches such as Basset and Basenji with newer transformer frameworks like Enformer and Borzoi. They highlight expanded receptive fields, multitask training on thousands of epigenomic tracks, and transfer-learning tricks that reduce data demands. Beyond cataloging successes, the review underscores persistent gaps: limited generalization to unseen cell states, inconsistent variant-effect direction predictions, and the heavy compute footprint of attention layers. It closes with future routes (foundation genomic language models, active-learning MPRA datasets, and interpretable surrogate networks) that could make S2E tools reliable enough for clinical genomics and synthetic-regulatory design.

Review highlights

  • Clarifies how receptive-field expansion (Basenji's dilated CNNs to Borzoi's 524-kb transformer-CNN hybrid) improves distal enhancer capture while tripling training footprints.

  • Reviews interpretability toolkits like saturated mutagenesis, gradient attribution, TF-MoDISco clustering, and surrogate linear models ,linking them to case studies that uncovered motif cooperativity rules.

  • Compares single-task versus multitask training and shows why balancing task weights or fine-tuning on personalized genomes boosts cell-type-specific accuracy.

Fig. 5
Figure 5 from Barbadilla-Martínez 2025: Main applications of sequence-to-expression models. Sequence-to-expression (S2E) models can be trained on transcription or epigenomic maps, massively parallel reporter assay (MPRA) data or a combination of these data types. These models have a number of applications. a, S2E models allow the regulatory logic of regulatory elements such as promoters and enhancers to be dissected. For example, S2E models can be used to identify cooperativity between transcription factors. b, These models can be used to identify the effects of non-coding sequence variants that occur within the human population. Genome-wide association studies often lack the resolution to directly identify the causal variant of the associated phenotype. S2E models could help in fine mapping, that is, in determining the genetic variant responsible for the trait under study. c, S2E models can be used to create synthetic regulatory elements either by iterative optimization, such as through evolutionary algorithms, or simply by evaluating millions of predictions and selecting the one with the desired predicted activity. This can aid with the design of regulatory elements with a desired activity or cell-type specificity or for use in biotechnology applications or for gene therapy purposes.

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Other papers of note

Refer to caption
Figure 1 from the BioReason paper.

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Additional details

Description

De novo mutation rates from a 4-gen pedigree, how LLMs internalize scientific literature, pedigree and genetic data simulations, a review on predicting gene expression from DNA sequence using LLMs...

Dates

Issued
2025-08-13T12:04:58
Updated
2025-08-13T12:04:58