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Jang Y et al., The American Journal of Human Genetics - Every cell in the body picks up its own small set of DNA changes over a lifetime, and many of these somatic mutations are carried by only a tiny fraction of cells. This study, part of the SMaHT Network, asks how reliably standard bulk whole-genome sequencing can find mutations present at a variant allele fraction below 1%. The team built a ground truth from one donor's skin: clonal stem cell lines grown from single fibroblasts defined real mutations, and lines from other skin biopsies of the same donor defined mutations that should be absent. With about 1,360× Illumina coverage confirmed by PacBio and AVITI, point mutations below 1% were detected accurately in the easily mapped parts of the genome. Key terms: somatic mosaicism, whole-genome sequencing, variant allele fraction, benchmarking, SMaHT. Study Highlights: Primary fibroblasts from a 29-year-old donor contained five subclones, captured as clonal iPSC lines, giving benchmark mutations from 0.1% to 25% variant allele fraction, while iPSC lines from other biopsies of the same donor supplied negative controls; both sets held about 11,000 SNVs and 2,800 indels. Using the negative controls, PacBio and AVITI had the lowest substitution error rates in easy regions, 0.003% and 0.005%, and mismatch rates rose by 1 to 2 orders of magnitude in harder regions. In fibroblasts, more than 99.5% of bulk-only calls above 1% were confirmed by PacBio or AVITI, the estimated false-positive rate was near zero above 0.8% and about 11% below 0.5%, and homopolymer indels could be detected reliably only above 3%. In postmortem lung and colon, combining about 200× from two tissues found 13 additional shared mutations, a 145% gain in sensitivity below 3%, all confirmed by PacBio or single-cell data. Conclusion: Ultra-deep bulk whole-genome sequencing can detect point mutations below 1% allele fraction with high accuracy, provided calling is restricted to easily mapped regions and sample quality is checked, and pooling coverage across tissues from one donor recovers shared developmental mutations. The benchmark comes from a single donor's fibroblasts, confirmation below 0.5% was limited by long-read and AVITI coverage, most indels sit in homopolymers or hard regions where detection remains unreliable, and postmortem samples needed extra filtering. Article title: Accurate detection of sub-1% frequency somatic mutations by whole-genome sequencing First author: Jang Y Journal: The American Journal of Human Genetics DOI: 10.1016/j.ajhg.2026.09.010 Reference: Jang Y., Gardiner S., Wang Y., Natu A., Dehankar M.K., Tomasini L., et al. Accurate detection of sub-1% frequency somatic mutations by whole-genome sequencing. The American Journal of Human Genetics. (2026). https://doi.org/10.1016/j.ajhg.2026.09.010 License: This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support: Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming: ❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01 ☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 ▶️ Watch with chapters on YouTube: https://www.youtube.com/@basebybase More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/detecting-sub-1-percent-somatic-mutations-wgs QC: This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-10-18. QC Scope: - article metadata...

Meyer-Schuman R et al., The American Journal of Human Genetics - Autism is diagnosed about four times more often in male individuals than in female individuals, and one explanation is mild variants in dosage-sensitive genes on the X chromosome, which a female carrier can buffer with her second copy but a male cannot. This study tests that idea in MECP2, the Rett syndrome gene, by looking at the switches that control how much of it is made rather than the gene itself. Using a massively parallel reporter assay in human stem-cell-derived neurons, the team mapped the active transcription factor binding sites in five MECP2 regulatory elements and tested 22 ultra-rare variants passed from unaffected mothers to autistic sons. Two variants changed regulatory activity, and one in the promoter lowered MECP2 RNA and protein by about 30% when edited into the native gene. Key terms: MECP2, autism, massively parallel reporter assay, noncoding variants, X chromosome. Study Highlights: Whole-genome data from 30,916 individuals in 8,245 autism families yielded 22 ultra-rare noncoding variants in MECP2 regulatory elements, each private to one family, found only in male probands and inherited from an unaffected mother, tested alongside 19 gnomAD control variants. Shuffling predicted transcription factor motifs mapped activator or repressor hotspots in four of the five elements, and knocking down two predicted activators, TCF3 and ZNF281, lowered MECP2 RNA by about 55% and 47% after three weeks. A variant in the primate-specific repressor element CRE A, carried by two affected brothers, increased activity in both the reporter and luciferase assays. The promoter variant g.154097837A>G, found in a boy with autism and ADHD and a full-scale IQ of 97, weakened NFY-B binding at the MECP2 promoter from the 51st to the 9th percentile of bound promoters and reduced MECP2 RNA and protein by about 30% in edited neurons. Conclusion: The findings suggest that noncoding MECP2 variants that modestly lower or raise expression can contribute to idiopathic, male-biased autism, and they provide a framework for finding regulatory variants in other X chromosome neurodevelopmental genes. The evidence rests on two families and on reporter assays and edited neurons in a dish, which take short sequences out of their native chromatin context, so the link between these variants and autism still needs additional variant discoveries and molecular validation. Article title: A massively parallel reporter assay of MECP2 cis-regulatory elements reveals genetic candidates for male-biased autism First author: Meyer-Schuman R Journal: The American Journal of Human Genetics DOI: 10.1016/j.ajhg.2026.09.011 Reference: Meyer-Schuman R., Cherry F., Sui Y., Papastathopoulos-Katsaros A., Zhong Y., Li Y., et al. A massively parallel reporter assay of MECP2 cis-regulatory elements reveals genetic candidates for male-biased autism. The American Journal of Human Genetics. (2026). https://doi.org/10.1016/j.ajhg.2026.09.011 License: This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support: Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming: ❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01 ☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 ▶️ Watch with chapters on YouTube: https://www.youtube.com/@basebybase More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/mecp2-regulatory-variants-male-biased-autism QC:... Chapters (00:00:20) - Introduction: A Family Mystery(00:01:19) - The X Chromosome and Autism's Male Bias(00:01:45) - The Dimmer Switch Analogy(00:02:35) - Introducing the Study and Authors(00:03:13) - MECP2 Gene and Dose Sensitivity(00:04:27) - Mouse Evidence for Narrow Safe Range(00:05:33) - The Broader X-Linked Puzzle(00:06:10) - Finding Candidate Regulatory Elements(00:06:45) - Selecting Variants from Families(00:07:20) - Massively Parallel Reporter Assay Explained(00:08:30) - Testing in Human Neurons(00:08:56) - Mapping Hotspots Across Elements(00:09:50) - Identifying Transcription Factors(00:10:27) - Switch Teamwork and Context Dependence(00:10:57) - Element A Variant in Two Brothers(00:12:14) - Promoter Variants and Luciferase Testing(00:12:48) - The Boy with the Promoter Variant(00:13:22) - CRISPR Validation of NFY Binding Loss(00:14:18) - Measuring the Downstream Effects(00:14:57) - What the Findings Add Up To(00:15:32) - Why Mild Cases Survive the Filter(00:16:03) - Beyond MECP2: Broader Implications(00:16:33) - Study Limitations(00:17:15) - Conclusion: Quiet Switches and the Future(00:18:13) - Closing and Credits

Lin et al., The American Journal of Human Genetics - Bi-allelic variants in IDUA classically cause mucopolysaccharidosis type I, a lysosomal storage disorder that affects many organs from childhood. This study describes 14 adults and young adults from 12 families who first came to eye clinics with retinitis pigmentosa and were later found to carry bi-allelic IDUA variants. Seven of them showed no systemic features of the disease even after detailed assessment, and enzyme activity in white blood cells was reduced but never absent. Cell-based enzyme assays and long-read RNA sequencing explain how mild, hypomorphic alleles can leave just enough enzyme to spare the body but not the retina. Key terms: IDUA, mucopolysaccharidosis type I, retinitis pigmentosa, hypomorphic variants, splicing. Study Highlights: Individuals aged 19 to 73 were recruited from inherited retinal disease cohorts in the UK, Ireland, Italy, the Netherlands and the United States, and none carried two null alleles; most had a loss-of-function allele paired with a missense variant. Leukocyte alpha-L-iduronidase activity was reduced but detectable in all nine individuals tested, and urine glycosaminoglycans were above normal in only half of those tested, with modest elevations. In an IDUA-knockout cell line, several missense variants, including p.His91Tyr and p.Arg383His, showed relative specific activity around 0.5% to 1.5% of wild type, with poor processing or stability. The recurrent c.298A>G variant left enzyme activity intact as a protein change, but nanopore long-read sequencing showed that it mostly causes exon 2 skipping, with only about 1.3% of reads from that allele spliced normally. Conclusion: Hypomorphic IDUA genotypes that leave low residual enzyme activity can cause late-onset retinitis pigmentosa with mild or apparently no systemic disease, extending the known spectrum of MPS I and arguing for including IDUA in inherited retinal disease gene panels. The cohort is small and mostly of European ancestry, systemic assessment varied in depth, and without longitudinal follow-up some individuals classed as having isolated retinal disease may still develop systemic features. Article title: Hypomorphic IDUA genotypes are associated with retinitis pigmentosa in individuals without syndromic mucopolysaccharidosis type I First author: Lin Journal: The American Journal of Human Genetics DOI: 10.1016/j.ajhg.2026.09.008 Reference: Lin, S., Yu, S.-H., Browning, A. C., et al., Roosing, S., Steet, R., and Arno, G. (2026). Hypomorphic IDUA genotypes are associated with retinitis pigmentosa in individuals without syndromic mucopolysaccharidosis type I. The American Journal of Human Genetics 113, 1-12. https://doi.org/10.1016/j.ajhg.2026.09.008 License: This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support: Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming: ❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01 ☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 ▶️ Watch with chapters on YouTube: https://www.youtube.com/@basebybase More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/idua-hypomorphic-retinitis-pigmentosa-mps-i QC: This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-10-11. QC Scope: - article metadata and core scientific claims from the narration - excludes analogies, intro/out... Chapters (00:00:20) - Introduction: Two Faces of One Gene(00:01:54) - The Lysosome Crew Analogy(00:03:01) - Study Overview and Authors(00:03:44) - Understanding IDUA and MPS1(00:04:23) - MPS1 Severity Spectrum and Eye Involvement(00:05:41) - The Unclear Case of Retina-Only Disease(00:06:54) - Study Cohort and Methods(00:08:06) - Clinical Eye Workup and Testing(00:08:38) - Measuring Enzyme Activity in the Lab(00:09:44) - RNA Sequencing of a Puzzling Variant(00:10:18) - Genetic Findings: One Null, One Missense(00:10:49) - Clinical Results: Retina Affected, Body Spared(00:12:01) - Biochemical Results: Reduced but Not Absent(00:12:37) - Variant-by-Variant Activity Results(00:13:50) - The Recurrent Splicing Variant Mystery(00:14:26) - Long-Read Sequencing Reveals Leaky Splicing(00:15:37) - Why the Retina Fails First(00:16:15) - Clinical Implications for Diagnosis and Panels(00:16:51) - Therapeutic Implications(00:17:18) - Newborn Screening Dilemma(00:17:55) - Study Limitations(00:18:31) - Conclusions and Open Questions(00:19:31) - Closing and Credits

Thorne et al., Proceedings of the National Academy of Sciences - GLP-1 receptor agonists such as semaglutide produce large weight loss, but part of what is lost is lean mass, energy expenditure falls, and weight tends to return when treatment stops. This study tests a complementary idea in mice: switching on heat-producing fat by silencing ZFP423, a repressor of brown and beige fat identity, with an adipose-targeted antisense oligonucleotide. The RNA drug raised energy expenditure and improved metabolism on its own, and combined with semaglutide it produced more weight and fat loss while roughly halving the loss of lean mass. Key terms: GLP-1 receptor agonist, ZFP423, antisense oligonucleotide, adipose thermogenesis, lean mass. Study Highlights: Antisense oligonucleotides against Zfp423 were linked to palmitic acid to reach fat tissue, and two of twelve candidates, ASO37 and ASO44, were selected for strong knockdown without signs of toxicity. In lean mice on chow, weekly treatment for 10 weeks beiged white fat, raised oxygen consumption and body surface temperature without changing activity, and improved glucose tolerance even though body weight stayed the same, while muscle and heart function were preserved. In obese mice, three doses lowered fasting triglycerides, glucose and body weight, and fat mitochondria from treated mice showed more than threefold higher oxygen consumption than controls, partly through UCP1 and partly through the futile creatine cycle. Combined with semaglutide, ASO37 produced 9.2 g of weight loss against 6.6 g for either drug alone, cut body fat to 4.2 g, and limited lean mass loss to 5.5% compared with about 10% with semaglutide alone. Conclusion: In mice, silencing ZFP423 in fat with an RNA drug turns on thermogenic beige fat and complements GLP-1 receptor agonist treatment by adding fat loss and sparing lean mass. The work was done only in mice, the antisense drugs target mouse Zfp423 rather than human ZNF423, combination studies lasted three weeks, and several authors are employees of Ionis Pharmaceuticals or inventors on a related patent application. Article title: An RNA thermogenic therapy to preserve lean mass and enhance metabolic health during GLP-1 weight loss First author: Thorne Journal: Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.2618845123 Reference: Thorne, A. K., Waldeck, N. J., Rose, J. P., Stachowski, M. J., Guak, H., Keeble, A. R., et al., and Bass, J. (2026). An RNA thermogenic therapy to preserve lean mass and enhance metabolic health during GLP-1 weight loss. Proceedings of the National Academy of Sciences 123(40), e2618845123. https://doi.org/10.1073/pnas.2618845123 License: This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support: Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming: ❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01 ☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 ▶️ Watch with chapters on YouTube: https://www.youtube.com/@basebybase More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/zfp423-rna-therapy-beige-fat-glp1-lean-mass QC: This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-10-06. QC Scope: - article metadata and core scientific claims from the narration - excludes analogies, intro/outro, and music - transcript coverage: Audited the ZFP423 rationale... Chapters (00:00:20) - Introduction: The Problem with Weight Loss Drugs(00:01:11) - GLP1 Drugs and Their Limitations(00:01:41) - A New Hypothesis: Burning Fat as Heat(00:02:12) - Study Overview and Publication(00:02:48) - Obesity, Fat Types, and Thermogenesis(00:04:00) - The Body Clock and ZFP423 Discovery(00:04:59) - Timing, Metabolism, and the Gene's Role(00:05:41) - Designing the Antisense Oligonucleotide Drug(00:06:47) - Single Cell Sequencing Methods(00:07:22) - Experimental Design Across Mouse Models(00:07:58) - Results in Lean Mice: Body Composition Shifts(00:08:29) - Organ and Hormone Effects(00:09:01) - Extra Eating but No Weight Gain: Energy as Heat(00:09:30) - Gene Expression Confirms Mechanism, Muscle Spared(00:10:02) - Testing in Obese Mice: Dose Response(00:10:33) - Heart Function Improvements(00:11:02) - Mitochondrial Mechanisms: Two Furnaces(00:12:08) - Single Cell Reorganization of Fat(00:12:45) - Combination Therapy: ASO Plus Semaglutide(00:13:19) - Preserving Muscle Mass and Function(00:14:21) - Energy Expenditure and Metabolic Outcomes(00:14:56) - Why This Matters for Obesity Treatment(00:15:26) - The Muscle Loss Concern Explained(00:15:56) - Study Limitations(00:16:31) - Conflicts of Interest Disclosure(00:16:59) - Conclusions and Future Outlook(00:17:48) - Closing and Credits

Zhu et al., Proceedings of the National Academy of Sciences - Genome-wide studies of schizophrenia and other psychiatric disorders find hundreds of hits, yet those hits barely clear the significance threshold and tend to be common variants, unlike traits such as LDL cholesterol. This study shows that other traits whose heritability is enriched in the central nervous system share the same pattern, that the pattern survives careful matching of statistical power between binary and quantitative traits, and that it is best explained by an evolutionary model in which brain-related traits have very large mutational targets and their variants face stronger selection. Key terms: genetic architecture, natural selection, GWAS, psychiatric genetics, mutational target size. Study Highlights: Using stratified LD score regression across 220 cell types, the authors classified 164 traits and found 50 brain-related quantitative traits and four brain-related disorders, all psychiatric, among 151 UK Biobank traits and 13 diseases. Schizophrenia hits had a narrower spread of z-scores and higher minor allele frequencies than LDL or coronary artery disease hits, and the difference remained after downsampling the other GWAS to the effective sample size of the schizophrenia study. Fitting a pleiotropic stabilizing selection model, they inferred a selection distribution shifted toward stronger selection for brain-related traits and a median mutational target of about 1.32% of the genome, against 0.27% for other traits. Simulations showed that stronger selection, once GWAS ascertainment is applied, enriches hits for common variants, and rare loss-of-function burden tests showed that highly constrained genes have larger effects on brain-related traits than on other traits. Conclusion: Traits mediated by the central nervous system share a distinct genetic architecture of many small, relatively common effects, which the authors attribute to large mutational target sizes and stronger selection on brain-relevant variants and genes. The brain-related traits studied act as proxies for the processes under selection, so the specific targets of selection cannot be identified, and confounding was not fully excluded because family-based GWAS remain underpowered. Article title: Genetic architectures of brain-related traits are shaped by strong selective constraints First author: Zhu Journal: Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.2609814123 Reference: Zhu, H., Simons, Y. B., Spence, J. P., Sella, G., and Pritchard, J. K. (2026). Genetic architectures of brain-related traits are shaped by strong selective constraints. Proceedings of the National Academy of Sciences 123(36), e2609814123. https://doi.org/10.1073/pnas.2609814123 License: This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support: Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming: ❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01 ☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 ▶️ Watch with chapters on YouTube: https://www.youtube.com/@basebybase More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/brain-traits-strong-selection-genetic-architecture QC: This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-10-04. QC Scope: - article metadata and core scientific claims from the narration - excludes analog... Chapters (00:00:20) - Introduction: The Loud Room and the Whisper Room(00:01:20) - The Puzzle: Weak, Common Hits in Psychiatric Genetics(00:02:31) - Study Overview and Research Team(00:03:08) - What Is Genetic Architecture and Why It Matters(00:04:14) - The Stabilizing Selection Model(00:05:30) - Identifying Brain-Related Traits(00:06:51) - Comparing Diseases and Traits Fairly(00:07:59) - Modeling Selection and Mutational Target(00:08:38) - Key Findings: LDL vs Coronary Disease vs Schizophrenia(00:09:43) - The Pattern Across Psychiatric and Behavioral Traits(00:10:54) - Ruling Out Study Design as the Explanation(00:11:32) - Evolutionary Signatures: Stronger Selection, Larger Targets(00:12:41) - Why Stronger Selection Produces Common Hits(00:13:19) - Independent Evidence from Gene Constraint(00:14:22) - Explaining the History of Psychiatric Genetic Discovery(00:14:58) - Why the Brain May Face Stronger Selection(00:15:35) - Limitations and Caveats(00:16:44) - Conclusions and Broader Implications(00:17:48) - Closing and Credits

Cheng et al., Proceedings of the National Academy of Sciences - Genome-wide studies have found dozens of risk loci for age-related macular degeneration, but for many of them the gene doing the work is unknown. This study combines AMD genetics with blood and retinal gene-expression data to prioritize nine candidate genes, screens them in zebrafish, and follows the strongest, CNN2, into knockout mice. Mice lacking Cnn2 lose sensitivity in dim light and to fine contrast while acuity stays normal, and their photoreceptor layer thins, even though the gene is expressed mainly in the retina's blood-vessel cells rather than in photoreceptors. Key terms: age-related macular degeneration, CNN2, statistical genetics, photoreceptor degeneration, retinal neurovascular homeostasis. Study Highlights: Summary-data-based Mendelian randomization combining an AMD genome-wide study of 16,144 cases and 17,832 controls with blood expression data from 2,765 people found 16 genes, and the HEIDI test kept 9 whose signals were not explained by linkage, 4 of which replicated in retinal data from 406 donors. In zebrafish larvae, morpholino knockdown of cnn2 shrank eye area by 48.5% and axial length by 32.5%, cut the light-on visual motor response by 61.9%, and both defects were largely rescued by injecting cnn2 mRNA. Cnn2 knockout mice at 3 months had a 39.2% lower a-wave and a 27.3% lower b-wave in dim-light electroretinograms and needed 15.3% contrast to respond where wild-type mice needed 4.1%, while bright-light responses and visual acuity were unchanged. The photoreceptor layer thinned by 3 and 5 months, cone arrestin and rhodopsin fell, and the 436 genes altered in the retina were enriched 6.02-fold near known AMD risk loci. Cnn2 was expressed mainly in endothelial cells and pericytes, and in human retinas it was lower in AMD but not significantly so. Conclusion: Human genetic evidence and experiments in two species converge on CNN2, a calponin gene active mainly in retinal blood-vessel cells, as a candidate susceptibility gene for age-related macular degeneration. The authors propose that its loss disturbs neurovascular balance and harms photoreceptors secondarily, but the data do not yet show whether the effect is direct or indirect, and neither model has a macula. Music: Enjoy the music based on this article at the end of the episode. Article title: Genetic evidence and cross-species functional characterization implicate CNN2 in age-related macular degeneration susceptibility First author: Cheng Journal: Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.2533682123 Reference: Cheng, F.-F., Mou, H., Liu, Z., Zhang, C.-J., Zhuang, Y.-Y., Wu, Z., Wen, X.-R., Xue, A., Zhang, X., Yang, J., and Jin, Z.-B. (2026). Genetic evidence and cross-species functional characterization implicate CNN2 in age-related macular degeneration susceptibility. Proceedings of the National Academy of Sciences 123(36), e2533682123. https://doi.org/10.1073/pnas.2533682123 License: This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support: Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming: ❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01 ☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 ▶️ Watch with chapters on YouTube: https://www.youtube.com/@basebybase More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/cnn2-amd-vessel-gene-low-light-vision-mice QC: This... Chapters (00:00:10) - Intro and the dimming eye metaphor(00:00:57) - The retina stage: performers and crew(00:02:28) - Macular degeneration: overview and prevalence(00:04:19) - The genetic gap: regions vs genes(00:05:28) - Mendelian randomization narrows candidates(00:06:29) - Validating candidates across tissues(00:07:21) - Zebrafish screening of candidate genes(00:08:30) - Zebrafish results: CNN2 and SARM1 effects(00:09:38) - Focusing on CNN2 in mice(00:10:11) - Mouse vision tests: contrast and sensitivity(00:11:17) - Retinal structure changes in knockout mice(00:11:44) - Where CNN2 is expressed: vessels not photoreceptors(00:12:46) - What is CNN2 and proposed mechanism(00:13:14) - Caveats and limitations of the study(00:14:27) - Significance and future implications(00:15:05) - Summary and closing thoughts(00:16:08) - Credits and outro(00:16:49) - Original song: The dimming eye ballad

Yoon et al., Proceedings of the National Academy of Sciences - ANK3, which encodes the scaffolding protein ankyrin-G, is a major risk gene for bipolar disorder and schizophrenia, yet what it does in adult neurons has been unclear. This study deletes Ank3 from mouse forebrain excitatory neurons either before birth or from adolescence and finds a convergent adult profile: hyperactivity and less anxiety-like and depression-like behavior, with social behavior intact. The neurons become less active, their membrane proteome shifts, and myelin basic protein falls, a protein made by oligodendrocytes rather than by the neurons that lost Ank3. Key terms: ANK3, ankyrin-G, bipolar disorder, myelin basic protein, lithium. Study Highlights: Deleting Ank3 prenatally with Emx1-Cre or from adolescence with CaMKIIα-Cre produced convergent adult phenotypes, including hyperactivity, reduced anxiety-like behavior and reduced immobility in the forced swim test, while the three-chamber social test was normal in both lines. Calcium imaging showed that ankyrin-G knockdown lowered spontaneous activity in cultured cortical neurons and that knockout slices gave smaller KCl-evoked calcium responses in layer 2/3 of somatosensory cortex. Quantitative TMT proteomics of the cortical membrane fraction quantified 2,357 proteins, of which 75 changed, 59 up and 16 down, and western blots confirmed higher Ryr2 and Taok2 and lower myelin basic protein. Mbp immunostaining was reduced in cortical layers 2/3 and 4 but not in layer 5 or hippocampal CA3, and myelin sheath diameter did not change significantly. A three-week lithium diet restored Mbp in the P3 fraction but not in the P2 membrane fraction, and left Ryr2 and Taok2 unchanged. Conclusion: Removing ankyrin-G from adult excitatory neurons is enough to produce hyperactive, low-anxiety mice with quieter neurons and less myelin basic protein, which ties a psychiatric risk gene in neurons to a myelin-associated protein made by glia. Lithium's selective restoration of Mbp suggests one possible myelin-related component of its action, although the cellular source of the Mbp change and any structural myelin deficit remain to be shown. Music: Enjoy the music based on this article at the end of the episode. Article title: Ank3 loss in adult forebrain excitatory neurons disrupts behavior, neuronal activity, membrane proteome, and myelination First author: Yoon Journal: Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.2606900123 Reference: Yoon, S., Dos Santos, M., Khalatyan, N., Savas, J.N., and Penzes, P. (2026). Ank3 loss in adult forebrain excitatory neurons disrupts behavior, neuronal activity, membrane proteome, and myelination. Proceedings of the National Academy of Sciences 123(35), e2606900123. https://doi.org/10.1073/pnas.2606900123 License: This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support: Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming: ❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01 ☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 ▶️ Watch with chapters on YouTube: https://www.youtube.com/@basebybase More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/ank3-adult-neurons-activity-myelin-basic-protein-lithium QC: This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-09-24. QC Scope: - article metada... Chapters (00:00:20) - Introduction: The hyperactivity paradox(00:02:02) - Meet ANK3 and ankyrin G's structural role(00:03:52) - Mouse model design: timing the gene deletion(00:06:19) - Behavioral tests: hyperactivity and reduced anxiety(00:08:34) - Calcium imaging reveals quiet neurons(00:10:17) - Proteomics: widespread molecular remodeling(00:12:09) - The myelin basic protein surprise(00:13:57) - Localizing the MBP deficit in the cortex(00:14:36) - Lithium treatment and the P2 fraction results(00:16:10) - Lithium's precise rescue in the synaptic P3 fraction(00:17:08) - Hypothesis: axoglial signaling breakdown(00:18:28) - Rethinking how mood stabilizers work(00:19:17) - Limitations and study boundaries(00:20:06) - Summary and implications for future treatment(00:20:43) - Closing and credits(00:21:57) - Original inspired track

Virolainen et al., The American Journal of Human Genetics - A lupus signal on chromosome 11p15 narrows to a coding haplotype in IRF7 that most people in the world carry. This study shows the risk form moves into the nucleus more readily, binds DNA more tightly and shifts its sequence preference, raising interferon-alpha output, and that mice engineered with the equivalent change clear a respiratory virus better while producing more anti-DNA autoantibodies. The same change buys antiviral protection and costs autoreactivity. Key terms: systemic lupus erythematosus, IRF7, type I interferon, evolutionary trade-off, fine mapping. Study Highlights: Fine mapping across ancestries placed the lupus association at 11p15 on a common coding IRF7 haplotype tagged by rs1131665 (p.Gln412Arg), with odds ratios of 1.20 in European and 1.15 in African ancestry cohorts and 1.18 in the trans-ancestral meta-analysis. The risk allele is carried by most of the world, reaching 98% in East Asian ancestry and 42% in African ancestry datasets, and ancient DNA spanning more than 40,000 years shows it was already common well before the recorded epidemics the authors examined. In cells the risk form increased IRF7 nuclear localization, strengthened DNA binding and altered its sequence specificity, raising interferon-alpha after stimulation of pattern recognition receptors in monocytes and airway epithelial cells. Mice carrying the analogous CRISPR-engineered Arg334Gln change in Irf7 had lower lung viral titers after intranasal vesicular stomatitis virus and produced significantly more anti-dsDNA autoantibodies than mice with the protective form. The authors read this as an evolutionary trade-off, in which the same gain in interferon output buys innate antiviral control at the price of autoreactivity. Conclusion: A coding haplotype in IRF7 that a majority of people carry tunes interferon-alpha upward, and that single setting produces both better early control of viral infection and a higher tendency to autoantibody production. Reading lupus risk at this locus as the cost of an antiviral advantage helps explain why such a variant stayed common, and it places interferon-directed therapy in a context where the same pathway is doing useful work. Music: Enjoy the music based on this article at the end of the episode. Article title: A highly prevalent lupus risk haplotype increases IRF7-dependent induction of IFN-α, enhancing antiviral defense and exacerbating autoimmunity First author: Virolainen Journal: The American Journal of Human Genetics DOI: 10.1016/j.ajhg.2026.08.016 Reference: Virolainen, S.J., Creighton, K., Dashtiahangar, M., et al., Waggoner, S.N., Weirauch, M.T., and Kottyan, L.C. (2026). A highly prevalent lupus risk haplotype increases IRF7-dependent induction of IFN-α, enhancing antiviral defense and exacerbating autoimmunity. The American Journal of Human Genetics 113, 1-22. https://doi.org/10.1016/j.ajhg.2026.08.016 License: This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support: Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming: ❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01 ☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 ▶️ Watch with chapters on YouTube: https://www.youtube.com/@basebybase More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/irf7-lupus-haplotype-interferon-antiviral-tradeoff QC: This episode was checked against the o... Chapters (00:00:14) - Intro: The evolutionary paradox of a 'bad' gene(00:02:15) - What is lupus? Understanding the disease(00:03:17) - IRF7: The master regulator of interferon response(00:04:44) - The globally dominant lupus risk variant(00:05:59) - Tracing the variant through ancient DNA(00:07:33) - Engineering cells with CRISPR to test the variant(00:08:36) - Validating mouse models for human immunity(00:10:46) - Findings: ancient persistence and cellular mechanics(00:11:57) - Doubling interferon: the biological amplifier effect(00:14:19) - Mouse trials: autoimmunity vs viral survival tradeoff(00:15:31) - The evolutionary bargain: survive now, pay later(00:16:51) - Treatment implications and the risk of turning off IRF7(00:18:15) - Future research and remaining mysteries(00:19:11) - Summary and closing thoughts(00:20:14) - Closing credits and outro song(00:20:38) - Original track: 'Same Dial, Both Ways'

Arterbery et al., The American Journal of Human Genetics - Hundreds of genes have been reported as causes of cerebral palsy, yet there is no agreed model of what a pathogenic variant in a child with CP actually means. This study treats CP as a phenotypic feature that some genetic disorders make more likely, tests the reported genes against the population prevalence of CP across tens of thousands of published individuals, and finds statistical evidence of association for only 89 of 515, before applying that stratification to genome sequencing of 460 children with CP. Key terms: cerebral palsy, Mendelian disease, genome sequencing, Human Phenotype Ontology, gene-disease association. Study Highlights: Across 21 published genomic diagnostic cohorts, variants deemed causal of cerebral palsy had been reported in 515 genes, with no consensus on whether such variants cause CP, mimic it, or coexist with it. The authors modelled CP as a phenotypic feature with a known population prevalence and applied a Bonferroni-corrected binomial test to 280 genes drawn from 5,508 publications describing 43,897 individuals, rejecting the null hypothesis of no association for 86 genes, and for 89 when combined with the genes enriched across the CP sequencing cohorts. Genome sequencing of 460 children with CP from 453 families at Shriners Children's identified pathogenic or likely pathogenic variants in 60 genes in 15.8% of the children. Only 16 of those 60 genes had significant literature evidence for CP association, which still represented a 16.3-fold enrichment over the overlap expected by chance. The results support a stratified approach in which the strength of evidence for each gene shapes how a molecular finding in a child with CP is interpreted. Conclusion: A pathogenic variant found in a child with cerebral palsy does not carry the same weight for every gene: for most of the 515 genes reported so far, the literature does not yet provide statistical evidence that the associated disorder raises the likelihood of CP. Treating CP as a phenotype with graded genetic evidence offers a framework for attributing causality more carefully in precision genomic diagnosis, while leaving open that more genes may prove to be associated as data accumulate. Music: Enjoy the music based on this article at the end of the episode. Article title: A phenotypic paradigm for cerebral palsy genetics First author: Arterbery Journal: The American Journal of Human Genetics DOI: 10.1016/j.ajhg.2026.08.007 Reference: Arterbery, A.S., Gargano, M.A., et al., and Robinson, P.N. (2026). A phenotypic paradigm for cerebral palsy genetics. The American Journal of Human Genetics 113, 1972-1986. https://doi.org/10.1016/j.ajhg.2026.08.007 License: This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support: Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming: ❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01 ☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 ▶️ Watch with chapters on YouTube: https://www.youtube.com/@basebybase More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/cerebral-palsy-genetics-phenotypic-model QC: This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-09-13. QC Scope: - article metadata and core scientific claims from the narration - excludes analogies, intro/outro, and music...

MacGregor et al., The American Journal of Human Genetics - Pathogenic TP53 variants found in blood have long been read as inherited Li-Fraumeni alleles, but many turn out to be somatic clones that grew with age. Using whole-exome data from 469,391 UK Biobank participants, this study combines variant allele fraction with haplotype sharing to tell the two origins apart, and finds that in cancer-free middle-aged adults the risk is mostly somatic and mostly hematological. Key terms: TP53, clonal hematopoiesis, Li-Fraumeni syndrome, UK Biobank, variant classification. Study Highlights: Rare coding TP53 variants were called in 469,391 UK Biobank participants aged 40 to 70, and 1,753 nonsynonymous variants were sorted by variant allele fraction combined with haplotype sharing across individuals carrying the same allele. Of 55 unique pathogenic TP53 variants detected, only six were classified as germline, and most of those sit at positions linked to partial rather than complete loss of p53 function. Classic Li-Fraumeni alleles behaved like somatic clonal expansions: their prevalence rose with age at an odds ratio of 2.3 per decade, while likely germline variants showed no age trend. Incident cancer risk separated sharply by origin, with the signal for somatic and inconclusive variants driven almost entirely by blood cancers rather than solid tumors, reaching a hazard ratio of 16.5 for the high-allele-fraction inconclusive class. The prevalence of somatic expansion tracked missense pathogenicity, suggesting that clonal growth in blood is itself an in vivo readout of how much a variant damages p53. Conclusion: In a population cohort of healthy middle-aged adults, most apparently pathogenic TP53 variants detected in blood reflect somatic clonal expansion rather than inherited predisposition, and the cancer risk they carry is predominantly hematological. Distinguishing the two origins with allele fraction and shared haplotypes gives a scalable way to interpret TP53 variants outside the clinic, where classic Li-Fraumeni assumptions do not hold. Music: Enjoy the music based on this article at the end of the episode. Article title: Shared inheritance reveals landscape of somatic and germline cancer risk in TP53 First author: MacGregor Journal: The American Journal of Human Genetics DOI: 10.1016/j.ajhg.2026.07.011 Reference: MacGregor, H.A.J., Blundell, J.R., and Easton, D.F. (2026). Shared inheritance reveals landscape of somatic and germline cancer risk in TP53. The American Journal of Human Genetics 113, 1916-1928. https://doi.org/10.1016/j.ajhg.2026.07.011 License: This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support: Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming: ❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01 ☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 ▶️ Watch with chapters on YouTube: https://www.youtube.com/@basebybase More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/tp53-somatic-germline-cancer-risk-biobank QC: This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-09-10. QC Scope: - article metadata and core scientific claims from the narration - excludes analogies, intro/outro, and music - transcript coverage: Audited the scientific body from the TP53 and Li-Fraumeni background through clonal hematopoiesis, the allele-f...

Quenez O et al., The American Journal of Human Genetics - Rare copy-number variants were called from 22,319 exomes covering early-onset Alzheimer disease, late-onset disease and unaffected controls, then tested gene by gene for a dosage effect. One locus came back with the cleanest signal in the field: at the central 22q11.21 region, deletions appeared only in early-onset cases, including one that arose de novo, while duplications piled up in controls, with late-onset cases sitting in between. Replication in nearly 400,000 further individuals confirmed it, and overexpressing SCARF2, one of the genes in the narrowed interval, increased amyloid-beta uptake in cells - the direction the protective duplications would predict. Key terms: copy-number variants, Alzheimer disease, 22q11.21, SCARF2, gene dosage. Study Highlights: The authors called rare copy-number variants from 22,319 harmonized exomes, comprising 4,150 early-onset Alzheimer cases at 65 years or younger, 8,519 late-onset cases and 9,650 unaffected controls, and found that early-onset cases carried an excess burden of rare CNVs affecting coding genes, driven particularly by deletions in genes already implicated in the disease. Pooling short truncating variants with deletions into a single loss-of-function analysis implicated ABCA1 with an odds ratio of 5.77 and ABCA7 deletions with an odds ratio of 2.29, and raised CTSB as a new candidate at an odds ratio of 5.03. An exome-wide gene-level dosage analysis then flagged 18 genes across five loci below a 10 percent false discovery rate, of which the central 22q11.21 region stood out: deletions were restricted to early-onset cases and absent from all 9,559 controls, duplications were enriched in controls, and late-onset cases fell in between, a gradient the authors narrowed to the SCARF2-KLHL22-MED15 interval. Replication across 33,977 additional cases and 362,322 controls confirmed the association at exome-wide significance, with duplications carrying an odds ratio of 0.34 and a mega-analysis p value of 5.52 times ten to the minus seven. Transfecting SCARF2 into microglial cells significantly increased uptake of fluorescent amyloid-beta with a p value of 2.2 times ten to the minus five, while uptake of inert latex beads did not change, arguing the effect is specific rather than a general boost in cell appetite. Conclusion: The same stretch of chromosome 22 pushes Alzheimer risk in opposite directions depending on how many copies you carry: losing one raises risk, gaining one lowers it. Duplications of the central 22q11.21 region emerge as one of the strongest risk-decreasing genetic factors described so far in terms of effect size, behind only the ultra-rare Icelandic APP variant, and unlike that variant they are found across multiple ancestries. The authors are careful about what this does not mean: the deletions are extremely rare, protection is relative rather than absolute, and they show it directly by pointing to duplication carriers who developed late-onset disease anyway while carrying other risk factors. Power is the central constraint, because each genome carries hundreds of rare coding point variants but typically only one rare coding CNV, and the analysis was restricted to individuals of European ancestry. Music: Enjoy the music based on this article at the end of the episode. Article title: Exome analysis of 22,319 individuals links extremely rare copy-number variants and 22q11.21 dosage to Alzheimer risk First author: Quenez O Journal: The American Journal of Human Genetics DOI: 10.1016/j.ajhg.2026.07.013 Reference: Quenez O, Schramm C, Cassinari K, Nicolas A, Groeneveld J, Huguet G, et al. Exome analysis of 22,319 individuals links extremely rare copy-number variants and 22q11.21 dosage to Alzheimer risk. The American Journal of Human Genetics. 2026;113(10):1-19. doi:10.1016/j.ajhg.2026.07.013 Li...

Fuhrer J et al., The American Journal of Human Genetics - Across 34 complex traits and disorders, a MiXeR-based framework partitions SNP heritability over 74 functional annotations and finds that exons carry only a minority of it, and steadily less as a trait becomes more polygenic. Exonic heritability falls from about 22 percent in less-polygenic somatic diseases and biomarkers to about 13 percent in highly polygenic psychiatric and cognitive traits, intergenic heritability rises by the same logic, and intronic heritability stays put. A new annotation contribution score shows the same axis in the annotations themselves: highly polygenic traits load on conservation and variant-effect scores, less-polygenic traits on promoter, transcription and chromatin marks. Key terms: polygenicity, SNP heritability, noncoding variation, functional annotation, complex traits. Study Highlights: The authors extended the MiXeR framework to model SNP effect-size variance across 74 binary functional annotations, applied it to 34 traits spanning psychiatric, neurological, cardiometabolic, anthropometric, hematological and immune phenotypes, and introduced a likelihood-based annotation contribution score that measures how much a single annotation adds to the full model rather than how enriched it is per SNP. Exons cover 2.55 percent of base pairs and account for a mean of 14.52 percent of heritability, with introns and intergenic regions together explaining the remaining 85.49 percent; introns alone typically carry about half. Regressing regional fractions on log polygenicity, the exonic fraction falls 4.38 percentage points and the intergenic fraction rises 4.87 percentage points per ten-fold increase in polygenicity, while the intronic slope is not significant, and the illustrative spread runs from 8.51 percent exonic in schizophrenia to 29.44 percent in sex-hormone-binding globulin. The contribution score peaks for mid-sized annotations covering roughly 10 to 15 percent of SNPs, so compact conservation tracks such as phastCons, GERP, CADD and Eigen dominate in highly polygenic traits while promoter and chromatin tracks such as H3K4me3 and CpG islands dominate in less-polygenic ones. Sensitivity analyses against sLDSC and sLD4M agreed closely, with heritability fractions correlating at r equals 0.996 and polygenicity estimates at Spearman r equals 0.91. Conclusion: The functional location of heritability is not a fixed property of the genome but tracks a trait's polygenicity: less-polygenic somatic traits concentrate heritability in coding and gene-proximal regulatory regions, while highly polygenic psychiatric and cognitive traits distribute it across dispersed distal regulatory elements. Because enrichment per SNP and total contribution can point in opposite directions, the authors argue both must be read together, and they note that coding variants explain a minority of heritability throughout, which argues for sequencing designs that maximize noncoding coverage. The analysis relies on European-ancestry reference panels, uses relatively broad annotations with incomplete chromosome X coverage, and depends on polygenicity estimates from two methods that nonetheless agreed closely. Music: Enjoy the music based on this article at the end of the episode. Article title: Beyond exons: Linking noncoding heritability and polygenicity across complex human traits and disorders First author: Fuhrer J Journal: The American Journal of Human Genetics DOI: 10.1016/j.ajhg.2026.08.012 Reference: Fuhrer J, Shadrin AA, Hughes T, Parker N, Hindley G, Frei E, Nguyen D, Smeland OB, Djurovic S, Andreassen OA, Dale AM, Frei O. Beyond exons: Linking noncoding heritability and polygenicity across complex human traits and disorders. The American Journal of Human Genetics. 2026;113(10):1-13. doi:10.1016/j.ajhg.2026.08.012 License: This episode is based...

Corpas M et al., Cell Genomics - A Perspective arguing that autonomous AI agents which discover, configure and chain bioinformatics operations from natural-language instructions have shifted the bottleneck in computational biology from building pipelines to validating their output. The authors define four necessary conditions for a system to count as agentic, propose a perturbation test that separates genuine runtime decision-making from pre-specified branching, survey four existing systems, and set out a three-tier validation framework in which none of the surveyed systems yet reaches clinical grade. Key terms: agentic genomics, AI agents, validation, skill libraries, equity in genomics. Study Highlights: The authors define agentic genomics through four necessary conditions — autonomy, domain constraint via validated skill libraries, iterative refinement, and natural-language mediation — and offer an empirically testable criterion: a system is not agentic if perturbed intermediate outputs fail to change its execution strategy. They distinguish the paradigm from workflow managers like Nextflow and Galaxy, from AutoML, from LLM-assisted scripting, and from general-purpose biomedical copilots. Four systems are surveyed and placed against a proposed three-tier validation framework of research grade, benchmarked and clinical grade; all four currently sit at research grade, and none has published the external multi-site evidence the clinical tier requires. The paper documents a concrete silent failure: in the early weeks of ClawBio, one skill given an empty input file containing no genomic data returned all-normal results including recommended dosages for 51 drugs, a path since closed by community audit. It also reports that a randomized trial of GPT-4-augmented diagnostic reasoning found no significant improvement over conventional resources, 76 percent versus 74 percent with p equal to 0.60, even though the model alone scored well above physicians. Conclusion: The central claim is that agentic genomics expands the capacity to produce analyses without expanding the capacity to judge them, so validation frameworks must be formalized and tiered, equity-aware defaults must be engineered rather than aspired to, and regulatory frameworks must accommodate non-deterministic software. The authors argue the paradigm is already in use and advancing, and that the open question is not whether it will be adopted but whether the field will build the standards to make it trustworthy first. Music: Enjoy the music based on this article at the end of the episode. Article title: Agentic genomics: From pipeline automation to autonomous validation First author: Corpas M Journal: Cell Genomics DOI: 10.1016/j.xgen.2026.101305 Reference: Corpas M, Guio H, Fatumo S. Agentic genomics: From pipeline automation to autonomous validation. Cell Genomics. 2026;6(8):101305. doi:10.1016/j.xgen.2026.101305 License: This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support: Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming: ❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01 ☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 ▶️ Watch with chapters on YouTube: https://www.youtube.com/@basebybase More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/agentic-genomics-validation-bottleneck QC: This episode was checked against the original article PDF and publication metadat...

Ali T et al., JCI Insight - Um antirretroviral aprovado para HIV, dado por via oral em microdose, prolongou a sobrevida de camundongos que carregam a proteína priônica humana e foram infectados com príons de doença de Creutzfeldt-Jakob esporádica humana. O efavirenz age ativando a CYP46A1, a enzima cerebral que converte colesterol numa forma capaz de sair do cérebro — e não baixando a proteína priônica, como as abordagens dos episódios anteriores desta série. Termos-chave: efavirenz, CYP46A1, doença de Creutzfeldt-Jakob, metabolismo do colesterol cerebral, reposicionamento de medicamento. ⚠️ Importante: nada neste episódio é motivo para tomar efavirenz. O efavirenz é um antirretroviral de prescrição com efeitos colaterais reais, incluindo distúrbio do sono, sonhos vívidos, tontura e efeitos psiquiátricos. A dose usada neste estudo — cerca de 0,09 mg/kg por dia — é algo entre 300 e 400 vezes menor que a dose prescrita para HIV, e não é algo que alguém consiga aproximar por conta própria. Nenhum ser humano teve benefício demonstrado com efavirenz para doença priônica. Existe um ensaio de Fase 3 registrado como NCT07482085 no ClinicalTrials.gov, que ainda não reportou resultados. Se a doença priônica afeta você ou sua família, converse com um neurologista e pergunte sobre ensaios registrados — não sobre a farmácia. Este é o quarto episódio da nossa série sobre a doença de Creutzfeldt-Jakob, que começou como homenagem ao Lito Sousa. Todos os ensaios citados na série estão registrados publicamente no ClinicalTrials.gov. Destaques do estudo: Os autores inocularam camundongos tg650, que superexpressam a PrP humana, com príons MM1 de CJD esporádica humana e começaram o efavirenz oral em dose baixa aos 30 ou aos 130 dias após a infecção, prolongando a sobrevida em 17 e 23 dias respectivamente. Na fase clínica inicial, os animais tratados apresentaram menos PrPSc, menor teor de colesterol e de gotículas lipídicas no cérebro, e níveis mais altos de CYP46A1 e de 24S-hidroxicolesterol no cérebro e no soro. Superexpressar a CYP46A1 sozinha em células neuronais infectadas já reduziu a PrPSc e elevou o 24S-hidroxicolesterol, ligando o efeito antipriônico à enzima e não a outra propriedade do remédio. A dose usada foi de cerca de 0,09 mg/kg por dia, algo entre 300 e 400 vezes menor que a dose padrão prescrita para HIV. A eficácia no início tardio importa clinicamente, porque o paciente chega depois que os sintomas começaram. Conclusão: O efavirenz oral em dose baixa ativa a CYP46A1, restaura a renovação de colesterol no cérebro, reduz o acúmulo de PrPSc e prolonga a sobrevida num modelo humanizado de CJD esporádica, o que sustenta avaliar melhor esse medicamento reposicionado em doença priônica humana. Música: Ouça a música criada a partir deste artigo no final do episódio. Título do artigo: Treatment with efavirenz extends survival in a Creutzfeldt-Jakob disease model by regulating brain cholesterol metabolism Primeiro autor: Ali T Revista: JCI Insight DOI: 10.1172/jci.insight.190296 Referência: Ali T, Cashion J, Hannaoui S, Ahmed-Hassan H, Schatzl H, Gilch S. Treatment with efavirenz extends survival in a Creutzfeldt-Jakob disease model by regulating brain cholesterol metabolism. JCI Insight. 2025;10(14):e190296. doi:10.1172/jci.insight.190296 Licença: Este episódio é baseado em um artigo de acesso aberto publicado sob a Licença Creative Commons Atribuição 4.0 Internacional (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Apoie: O Base by Base é independente e sem anúncios — sem patrocinadores, sem paywall. Se o episódio valeu o seu tempo, contribua e ajude a manter os artigos auditados e as músicas originais: ❤️ Apoio mensal: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01 ☕ Doação única: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Mais em basebybase.com

Ali T et al., JCI Insight - Repurposed low-dose efavirenz slowed disease progression and extended survival in tg650 mice inoculated with MM1 sCJD prions by activating CYP46A1, raising 24S‑hydroxycholesterol and reducing PrPSc, brain cholesterol and lipid droplets at the early clinical stage. Key terms: efavirenz, CYP46A1, Creutzfeldt-Jakob disease, cholesterol metabolism, prion disease. ⚠️ Important: nothing in this episode is a reason to take efavirenz. Efavirenz is a prescription antiretroviral with real side effects, including sleep disturbance, vivid dreams, dizziness and psychiatric effects. The dose used in this study — about 0.09 mg/kg per day — is roughly 300 to 400 times lower than the dose prescribed for HIV, and is not something anyone can approximate on their own. No human being has yet been shown to benefit from efavirenz for prion disease. A Phase 3 trial is registered as NCT07482085 on ClinicalTrials.gov and has not reported results. If prion disease affects you or your family, talk to a neurologist and ask about registered trials — not about a pharmacy. This episode is the fourth in our series on Creutzfeldt-Jakob disease, which began as a dedication to Lito Sousa. Every trial named in the series is registered publicly on ClinicalTrials.gov. Study Highlights: Oral low-dose efavirenz given to human-PrP–overexpressing tg650 mice starting at 30 or 130 days postinoculation significantly slowed clinical progression and extended survival by 17 and 23 days, respectively. At the early clinical stage EFV-treated mice showed reduced PK-resistant PrPSc, decreased brain cholesterol and lipid droplets, and increased CYP46A1 expression with higher 24S‑hydroxycholesterol in brain and serum. Overexpression of CYP46A1 in prion-infected neuronal cells likewise reduced PrPSc, supporting a causal link between CYP46A1 activation and antiprion effects. Conclusion: Low-dose oral efavirenz activates CYP46A1, restores cholesterol turnover, reduces early PrPSc accumulation and lipid pathology, and extends survival in a humanized sCJD mouse model, supporting EFV as a candidate for further evaluation in human prion disease. Music: Enjoy the music based on this article at the end of the episode. Article title: Treatment with efavirenz extends survival in a Creutzfeldt-Jakob disease model by regulating brain cholesterol metabolism First author: Ali T Journal: JCI Insight DOI: 10.1172/jci.insight.190296 Reference: Ali T, Cashion J, Hannaoui S, Ahmed-Hassan H, Schatzl H, Gilch S. Treatment with efavirenz extends survival in a Creutzfeldt-Jakob disease model by regulating brain cholesterol metabolism. JCI Insight. 2025;10(14):e190296. https://doi.org/10.1172/jci.insight.190296. License: This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support: Base by Base is independent and ad-free — no sponsors, no paywall. If an episode was worth your time, chip in and keep the papers audited and the original songs coming: ❤️ Support monthly: https://buy.stripe.com/cNifZhclVebvagk2JDgEg01 ☕ One-time donation: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 More at basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/efavirenz-prion-cjd-cholesterol QC: This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-08-31. QC Scope: - article metadata and core scientific claims from the narration - excludes analogies, intro/outro, and music - transcript coverage: Audited the transcript's core biomedical claims about EFV's e...