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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:
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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/outro, and music
- transcript coverage: Audited the MPS I background and prior retina-predominant cases, cohort recruitment and phasing, eye and biochemical testing, the cell-based activity assay and western blot, nanopore splicing of c.298A>G, the retinal vulnerability model, clinical and newborn screening implications, and limitations.
- transcript topics: IDUA, glycosaminoglycan storage and the MPS I severity spectrum; Cohort of 14 individuals presenting with retinitis pigmentosa; Leukocyte enzyme activity and urine GAG testing; Relative specific activity and processing of missense variants; Long-read splicing analysis of the recurrent c.298A>G variant; Retinal vulnerability, gene panels, therapy and newborn screening

QC Summary:
- factual score: 10/10
- metadata score: 10/10
- supported core claims: 8
- claims flagged for review: 0
- metadata checks passed: 4
- metadata issues found: 0

Metadata Audited:
- article_doi
- article_title
- article_journal
- license

Factual Items Audited:
- 14 individuals from 12 families, aged 19 to 73, all presenting with retinitis pigmentosa
- Seven of nine comprehensively assessed had no MPS I features at ages 46 to 73
- No bi-allelic null genotypes; most had a loss-of-function allele plus a missense variant
- Leukocyte activity reduced but not abolished in all nine tested; urine GAG elevated in half
- RSA about 0.5% to 1.5% with poor processing for several missense variants
- c.298A>G in six individuals; 96 of 1,574,498 gnomAD alleles; no activity loss as a missense change

QC result: Pass.

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:
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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, ASO design and screening, chow-fed metabolism and muscle and heart safety, dose response and mitochondrial assays in obese mice, the semaglutide combination, single-nucleus RNA-seq, and the stated limitations and competing interests.
- transcript topics: ZFP423 as a transcriptional brake on brown and beige fat identity; Palmitate-conjugated antisense oligonucleotides targeting Zfp423 in fat; Beiging, energy expenditure and glucose tolerance in chow-fed mice; Dose-dependent effects and mitochondrial UCP1 and creatine-cycle respiration in obese mice; Combination with semaglutide: weight, fat and lean mass; Single-nucleus RNA-seq of beige adipocyte programs

QC Summary:
- factual score: 10/10
- metadata score: 10/10
- supported core claims: 7
- claims flagged for review: 0
- metadata checks passed: 4
- metadata issues found: 0

Metadata Audited:
- article_doi
- article_title
- article_journal
- license

Factual Items Audited:
- Twelve candidate ASOs screened; ASO37 and ASO44 selected
- Improved glucose tolerance within 4 weeks with unchanged body weight
- Higher oxygen consumption and surface temperature with unchanged locomotor activity
- About 70% knockdown after one dose; greater than 75% at 50 mg/kg
- Mitochondrial oxygen consumption more than threefold vs PBS; 39% drop with GDP; 50% rise with creatine
- Combination weight loss 9.2 g vs 6.6 g; body fat 4.2 vs 6.4 and 7.9 g

QC result: Pass.

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
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▶️ 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 analogies, intro/outro, and music
- transcript coverage: Audited the problem framing, trait classification with S-LDSC, power matching via the liability threshold model, the schizophrenia versus LDL and CAD comparison, the selection-model inferences, the ascertainment simulations, the LoF burden tests, the GWAS-discovery predictions and the stated limitations.
- transcript topics: Weak, high-frequency GWAS hits for schizophrenia versus LDL and coronary artery disease; Classifying brain-related traits by CNS heritability enrichment with S-LDSC; Matching statistical power between binary and quantitative traits; Pleiotropic stabilizing selection model: selection strength and mutational target size; Simulations of GWAS ascertainment under strong selection; Rare loss-of-function burden tests binned by gene constraint

QC Summary:
- factual score: 10/10
- metadata score: 10/10
- supported core claims: 8
- claims flagged for review: 0
- metadata checks passed: 4
- metadata issues found: 0

Metadata Audited:
- article_doi
- article_title
- article_journal
- license

Factual Items Audited:
- 151 quantitative traits and 13 diseases; 50 brain-related quantitative traits and four psychiatric disorders
- 220 cell types in 10 categories used for S-LDSC enrichment
- Schizophrenia hits narrowly exceed significance and have higher MAF
- Differences persist after matching to an effective sample size of 192,273
- Median mutational target 1.32% of the genome versus 0.27%
- Stronger selection yields higher-MAF hits after GWAS ascertainment

QC result: Pass.

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 episode was checked against the original article PDF and publication metadata for the episode release published on 2026-09-30.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Audited from the AMD burden and genetics through SMR and HEIDI prioritization, retinal and multi-tissue replication, the zebrafish screen and rescue, the Cnn2 knockout mouse phenotypes, transcriptomics, cell-type expression, the proposed mechanism and the stated limitations.
- transcript topics: AMD prevalence, projections and risk factors; GWAS loci and heritability; SMR and HEIDI gene prioritization; Retinal and GTEx replication; Zebrafish morpholino knockdown and mRNA rescue; Visual motor response in larvae

QC Summary:
- factual score: 10/10
- metadata score: 10/10
- supported core claims: 8
- claims flagged for review: 0
- metadata checks passed: 4
- metadata issues found: 0

Metadata Audited:
- article_doi
- article_title
- article_journal
- license

Factual Items Audited:
- Prevalence of 8.69% at ages 45 to 85 and 288 million affected by 2040
- At least 63 loci explaining over half of heritability
- 16,144 cases, 17,832 controls and 2,765 blood eQTL samples
- 16 SMR genes reduced to 9 by HEIDI, 4 replicated in 406 retinas
- All nine genes significant in at least two of 48 tissues
- Four genes with over 60% zebrafish similarity

QC result: Pass.

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
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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 metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Audited from the ANK3 and ankyrin-G background through the two deletion timelines, the behavioral battery, calcium imaging, membrane proteomics, the Mbp findings, the lithium experiment, the axoglial hypothesis and the stated limitations.
- transcript topics: ANK3 as a GWAS risk gene for bipolar disorder and schizophrenia; Ankyrin-G at the axon initial segment and synapses; Prenatal Emx1-Cre versus adolescent-onset CaMKIIα-Cre deletion; Open field, elevated zero maze and forced swim results; Calcium imaging in cultured neurons and acute slices; TMT proteomics of the P2 membrane fraction

QC Summary:
- factual score: 9/10
- metadata score: 10/10
- supported core claims: 5
- claims flagged for review: 3
- metadata checks passed: 4
- metadata issues found: 0

Metadata Audited:
- article_doi
- article_title
- article_journal
- license

Factual Items Audited:
- ANK3 flagged by GWAS for bipolar disorder and schizophrenia
- GWAS described as covering hundreds of thousands of people
- Ankyrin-G located at the axon initial segment and synapses
- Emx1-Cre deletes prenatally and CaMKIIα-Cre in adolescence or adulthood
- Timing of deletion said not to change the traits at all
- Hyperactivity, reduced anxiety-like and depression-like behavior

QC Flagged Items (audited and not fully supported):
- Core claim uncertain: Deleting Ank3 before birth or in adulthood made no difference at all to the behavioral traits.
- Core claim uncertain: Taok2 is linked to autism spectrum disorder.
- Core claim uncertain: Lithium physically repairs the axoglial communication infrastructure at the synapse.
Internal QC note: manual editorial review is recommended before publication.

QC result: Warning. Items above were flagged during automated QC; the editorial team reviewed them before release.

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 original article PDF and publication metadata for the episode release published on 2026-09-21.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Audited from the lupus background and IRF7 biology through fine mapping, global frequencies, ancient DNA, cell lines, protein-binding microarrays, the mouse model, the IFN-alpha results, the VSV challenge, the trade-off reading and the therapeutic outlook.
- transcript topics: Lupus heritability and GWAS background; IRF7 as master regulator of type I interferon; Coding haplotype at chromosome 11p15; Global allele frequencies across ancestries; Ancient DNA and the rs11246213 proxy marker; Reconstituted IRF7-deficient THP-1 and A549 lines

QC Summary:
- factual score: 8/10
- metadata score: 10/10
- supported core claims: 5
- claims flagged for review: 3
- metadata checks passed: 4
- metadata issues found: 0

Metadata Audited:
- article_doi
- article_title
- article_journal
- license

Factual Items Audited:
- Lupus heritability stated as 43% to 66%
- Risk haplotype reaching 98% in East Asian and 42% in African ancestry
- A European ancestry frequency of about 73%
- Ancient genomes dating back about 43,000 years
- rs11246213 used as a perfectly linked proxy marker
- Haplotype already prevalent by 10,000 BCE and stable since

QC Flagged Items (audited and not fully supported):
- Core claim uncertain: The haplotype was actively selected for by environmental pressures.
- Core claim uncertain: CRISPR was used to strip the natural IRF7 gene out of human cell lines and drop in each haplotype.
- Core claim uncertain: The cell lines used were common laboratory lines of human lung tissue.
- Numeric claim uncertain: Risk haplotype at around 73% in European ancestry
Internal QC note: manual editorial review is recommended before publication.

QC result: Warning. Items above were flagged during automated QC; the editorial team reviewed them before release.

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
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▶️ Watch with chapters on YouTube: https://www.youtube.com/@basebybase
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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
- transcript coverage: Audited the scientific body: the shift to genetic explanations of CP and 515 candidate genes, the two-pronged methodology with HPO encoding and Exomiser, the Poisson and binomial tests, the 89-gene result and Shriners cohort yield, the CTNNB1 and LIPH examples, the limitations, and the phenotypic paradigm.
- transcript topics: Shift from perinatal-injury to genetic explanations of CP; 515 candidate genes across 21 CP sequencing cohorts; Literature curation and gene-specific cohorts; HPO text mining with fenominal, phenopackets and Exomiser; Poisson and binomial tests against CP population prevalence; 89 of 515 genes with evidence and the Shriners cohort yield

QC Summary:
- factual score: 9/10
- metadata score: 10/10
- supported core claims: 5
- claims flagged for review: 3
- metadata checks passed: 4
- metadata issues found: 0

Metadata Audited:
- article_doi
- article_title
- article_journal
- license

Factual Items Audited:
- 21 CP NGS cohorts with 5,440 individuals and 515 genes
- Binomial test on 280 gene-specific cohorts from over 43,000 individuals
- Poisson test on the CP NGS cohort genes
- CP background prevalence taken as 0.3%
- Null hypothesis rejected for 89 of 515 genes
- 460 children sequenced, P/LP variants in 60 genes, 15.8% yield

QC Flagged Items (audited and not fully supported):
- Core claim uncertain: The 44 genes in the Shriners cohort without literature evidence were merely present in those children and not responsible for their CP.
- Core claim uncertain: The individual reported with a LIPH variant probably had a separate perinatal hypoxic event that actually caused the CP.
- Core claim uncertain: Finding a P/LP variant in a gene with established CP association lets clinicians know the child's trajectory with certainty and start intervention early.
Internal QC note: manual editorial review is recommended before publication.

QC result: Warning. Items above were flagged during automated QC; the editorial team reviewed them before release.

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-fraction and haplotype-sharing methodology, the classification results, the incident cancer risk analysis, the somatic-expansion-as-functional-proxy argument, and the stated limitations.
- transcript topics: TP53 function and Li-Fraumeni syndrome penetrance; Clonal hematopoiesis and somatic clonal expansion in bone marrow; Variant allele fraction and why it fails alone at high VAF; Haplotype sharing and identity by descent via GERMLINE2; Classification split of pathogenic TP53 variants in UK Biobank; Incident cancer risk by variant origin, hematological versus solid

QC Summary:
- factual score: 10/10
- metadata score: 10/10
- supported core claims: 7
- claims flagged for review: 0
- metadata checks passed: 4
- metadata issues found: 0

Metadata Audited:
- article_doi
- article_title
- article_journal
- license

Factual Items Audited:
- 315 individuals carrying pathogenic or likely pathogenic TP53 variants
- 87% of pathogenic TP53 variants classified by the combined method
- 70% somatic, 17% germline, 13% inconclusive
- Minimum shared haplotype segment length of 1.5 cM
- Hazard ratio 16.5 for hematological cancer in the inconclusive group
- No prospective hematological cancers among germline carriers

QC result: Pass.

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

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/22q11-dosage-alzheimer-risk-cnv-exome

QC:
This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-09-09.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Substantively audited from the framing of copy-number variants through the Down syndrome and chromosome 21 precedent, how read depth reveals deletions and duplications in exome data, the integrated loss-of-function burden approach, the cohort sizes and replication, the risk genes ABCA1, ABCA7 and CTSB, the fragility…
- transcript topics: Copy-number variants as deletions and duplications of genomic segments; Down syndrome and chromosome 21 as the dosage precedent in Alzheimer disease; Detecting copy number from exome read depth; Integrated loss-of-function analysis combining truncating variants with deletions; Discovery cohort of 22,319 exomes and the replication cohort; ABCA1, ABCA7 and CTSB as risk genes

QC Summary:
- factual score: 10/10
- metadata score: 10/10
- supported core claims: 8
- claims flagged for review: 0
- metadata checks passed: 4
- metadata issues found: 0

Metadata Audited:
- article_doi
- article_title
- article_journal
- license

Factual Items Audited:
- 22,319 exomes analyzed in discovery, comprising early-onset and late-onset cases and unaffected controls
- replication in 33,977 affected individuals and 362,322 control subjects
- ABCA7 deletions odds ratio 2.29 and ABCA1 loss of function odds ratio 5.77
- CTSB loss-of-function alleles as candidates
- 18 genes across five loci at a false discovery rate below 10 percent
- 22q11.21 deletions restricted to early-onset cases, duplications enriched in controls

QC result: Pass.

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 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/beyond-exons-noncoding-heritability-polygenicity

QC:
This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-09-08.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Substantively audited from the opening framing of coding versus noncoding heritability through the definition of polygenicity, the GWAS and summary-statistics explanation, the MiXeR framework and linkage disequilibrium handling, the 74-annotation panel, the annotation contribution score and its size correction…
- transcript topics: Coding versus noncoding heritability and the historical focus on exons; Polygenicity as the number of contributing variants; GWAS summary statistics as the input data; MiXeR framework and linkage disequilibrium correction; The 74-annotation functional panel and its seven domains; Annotation contribution score and correcting for annotation size

QC Summary:
- factual score: 9/10
- metadata score: 10/10
- supported core claims: 6
- claims flagged for review: 2
- metadata checks passed: 4
- metadata issues found: 0

Metadata Audited:
- article_doi
- article_title
- article_journal
- license

Factual Items Audited:
- exons cover 2.55 percent of base pairs; introns 45 percent and intergenic regions 52.45 percent
- mean exonic heritability 14.52 percent across 34 traits, with 85.49 percent in introns plus intergenic regions
- exonic fraction about 22 percent in less-polygenic somatic traits versus about 13 percent in highly polygenic psychiatric and cognitive traits
- per ten-fold polygenicity increase: exonic slope minus 4.38, intergenic plus 4.87, intronic not significant
- introns alone carry roughly half of heritability and that share is stable across polygenicity
- conserved intronic heritability rises with polygenicity while the nonconserved component falls

QC Flagged Items (audited and not fully supported):
- Core claim uncertain: Humans have roughly 20,000 protein-coding genes, about the same as the nematode C. elegans, which shows that gene count cannot explain organismal complexity.
- Core claim uncertain: The findings mean medicine must move to a network paradigm, identifying the hub where dispersed regulatory signals converge and developing a compound that nudges the whole network
Internal QC note: manual editorial review is recommended before publication.

QC result: Warning. Items above were flagged during automated QC; the editorial team reviewed them before release.