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Lambton J et al., The American Journal of Human Genetics - Bi-allelic ATG12 variants disrupt ATG12‑ATG5 conjugation and LC3 lipidation, impairing autophagy in patient cells and model systems and causing cerebellar vermis hypoplasia. Key terms: ATG12, autophagy, neurodevelopmental disorder, zebrafish, LC3 lipidation.

Study Highlights:
The study characterized six affected individuals with bi-allelic ATG12 variants using patient fibroblasts, HeLa ATG12 knockout complementation, yeast complementation, and CRISPR zebrafish models. Methods included WES/WGS and Sanger sequencing, immunoblotting, LC3/p62 flux assays, HaloTag-LC3 processing, LDH sequestration, AlphaFold-Multimer structural modeling, yeast GFP-Atg8 assays, and zebrafish behavioral and imaging assays. Structural modeling and biochemical data indicate variants map to ATG12 interfaces with ATG5 and ATG3, destabilize ATG12 or its conjugate with ATG5, reduce LC3/Atg8 lipidation and autophagic flux in a variant-dependent manner. Functionally, ATG12 disruption associates with neurodevelopmental phenotypes including cerebellar vermis hypoplasia, ataxia and seizures in humans, and causes growth, brain-structure and locomotor defects with reduced survival in zebrafish.

Conclusion:
Bi-allelic ATG12 variants impair ATG12 function and autophagy, producing a recessive neurodevelopmental disorder marked by cerebellar vermis hypoplasia and neurological deficits.

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Article title:
Bi-allelic ATG12 variants impair autophagy and cause a neurodevelopmental disorder

First author:
Lambton J

Journal:
The American Journal of Human Genetics

DOI:
10.1016/j.ajhg.2026.03.002

Reference:
Lambton J, Asano S, Huang Y, Suomi F, Eguchi T, Petree C, Huang K, Prigent M, Imam A, McCorvie TJ, Warren D, Hobson E, McCullagh H, Misceo D, Bjerre A, Smeland MF, Klingenberg C, Frengen E, Naik S, Ryan G, Sudarsanam A, Foster K, Vasudevan P, Samanta R, Rahman F, Maqbool S, Udani V, Efthymiou S, Houlden H, McFarland R, Collier JJ, Maroofian R, Yue WW, Varshney GK, Klionsky DJ, Legouis R, McWilliams TG, Mizushima N, Oláhová M, Alston CL, Taylor RW. Bi-allelic ATG12 variants impair autophagy and cause a neurodevelopmental disorder. The American Journal of Human Genetics. 2026 May 7;113:1–18. https://doi.org/10.1016/j.ajhg.2026.03.002

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 – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00

Official website https://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/biallelic-atg12-autophagy-disorder

QC:
This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-03-27.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Audited substantive scientific content from the transcript, focusing on the patient cohort, molecular mechanism (ATG12-ATG5 conjugation, LC3 lipidation), structural modeling, model organisms (yeast, zebrafish), and neurological phenotype.
- transcript topics: Bi-allelic ATG12 variants and patient cohort; ATG12-ATG5 conjugation and LC3 lipidation; AlphaFold/structural modeling of ATG12 interactions; Yeast and zebrafish functional assays; Cerebellar involvement and mitophagy; Therapeutic implications of autophagy modulation

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:
- Six individuals from five unrelated families with bi-allelic ATG12 variants were described.
- ATG12-ATG5 conjugate loss was observed in one family (S2) and an intact conjugate in another (S3).
- Autophagy flux was altered in subject-derived cells under starvation conditions.
- Zebrafish atg12 knockout showed developmental delay, brain defects, reduced locomotion, and pre-adult lethality.
- Yeast complementation showed hypomorphic, partial-function ATG12 variants; AlphaFold-Multimer modeling placed variants near ATG12 interfaces with ATG5/ATG3.
- Cerebellar vermis hypoplasia and related neurodevelopmental phenotypes were highlighted as key clinical features.

QC result: Pass.

Strand LG et al., Proc. Natl. Acad. Sci. U.S.A - In C. elegans germline, the deubiquitinase DUO-1 is required for assembly and active maintenance of the synaptonemal complex and REC-8 cohesin, preventing RAD-51 accumulation and ensuring diakinesis compaction. Key terms: DUO-1, Caenorhabditis elegans, synaptonemal complex, REC-8, auxin-inducible degron.

Study Highlights:
Using C. elegans germline as a developmental timecourse model, the authors combined cytological analyses (immunofluorescence, FISH, RAD-51/MSH-5/COSA-1 staining), temporally controlled auxin-inducible degron (AID) depletion, and TurboID proximity labeling with LC–MS to probe DUO-1 function. Loss or acute depletion of DUO-1 impairs SC assembly, leads to progressive axis/SC instability, depletion of REC-8 cohesin from chromosomes, hyperaccumulation of RAD-51-marked early DSB repair intermediates, and premature sister-chromatid separation. TurboID identifies PARG-1 and cohesin/HORMAD components as proximal partners and DUO-1::GFP localizes to nucleoplasm and a subset of chromosome axes, most prominently in late pachytene/early diplotene. Temporal AID experiments show DUO-1 is required continuously for early SC assembly, late-pachytene SC maintenance, and rapid preservation of diakinesis chromosome compaction, implying an active maintenance role for DUO-1 in preserving chromosome architecture during meiotic prophase.

Conclusion:
DUO-1 is continuously required throughout meiotic prophase in C. elegans to promote assembly and maintain stability of chromosome axes and synaptonemal complexes, protect REC-8 cohesin distribution, limit accumulation of early DSB repair intermediates, and ensure late-prophase chromosome compaction.

Music:
Enjoy the music based on this article at the end of the episode.

Article title:
Active maintenance of meiosis-specific chromosome structures in Caenorhabditis elegans by the deubiquitinase DUO-1

First author:
Strand LG

Journal:
Proc. Natl. Acad. Sci. U.S.A

DOI:
10.1073/pnas.2532671123

Reference:
Strand LG, Choi CP, McCoy S, Nsamba ET, Silva N, Villeneuve AM. Active maintenance of meiosis-specific chromosome structures in Caenorhabditis elegans by the deubiquitinase DUO-1. Proc. Natl. Acad. Sci. U.S.A. 2026;123(12):e2532671123. https://doi.org/10.1073/pnas.2532671123

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 – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00

Official website https://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/duo-1-c-elegans-meiosis

QC:
This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-03-25.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Audited the spoken scientific content reflecting the paper's core findings: DUO-1’s continuous maintenance of meiosis-specific chromosome structures, SC/axis stability, REC-8 cohesin protection, RAD-51 dynamics, AID-time course revealing separable roles, and the DUO-1–PARG-1 interaction revealed by TurboID.
- transcript topics: Meiotic prophase architecture (SC/axis) and DUO-1 roles; Duo-1 mutant phenotypes: SC assembly failure and polycomplexes; REC-8 cohesin distribution and sister chromatid cohesion; RAD-51 dynamics and SPO-11 dependency; COSA-1 foci and recombination intermediates; Auxin-inducible degradation (AID) reveals separable roles in assembly, maintenance, and compaction

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:
- DUO-1 is continually required throughout meiotic prophase to promote axis/SC assembly, maintain axis/SC stability, and promote/maintain chromosome compaction by the end of prophase
- Duo-1 mutants show impaired SC assembly and polycomplex formation; REC-8 cohesin distribution is lost as SCs disassemble
- RAD-51 foci hyperaccumulate in duo-1 mutants in a SPO-11–dependent manner
- Auxin-inducible degradation (AID) of DUO-1 reveals separable roles in SC assembly (early prophase), maintenance (late pachytene), and chromosomal compaction (diakinesis)
- TurboID proximity labeling identifies DUO-1 near PARG-1 and axis components; PARG-1 localization is impaired in duo-1 mutants but enzymatic activity persists and PAR does not accum
- DUO-1 is a deubiquitinase that protects cohesin/axis components from ubiquitin-mediated turnover

QC result: Pass.

Lawrence et al., The American Journal of Human Genetics - Using a cis-principal-component (pcQTL) approach in human GTEx tissues, the authors uncover novel multi-gene regulatory variants and 33% more GWAS colocalizations than single-gene eQTLs. Key terms: pcQTL, allelic proxitropy, GTEx, colocalization, HOXB.

Study Highlights:
The study analyzes 13 human GTEx tissues and identifies clusters of co-expressed neighboring genes, then applies PCA to cluster expression and maps cis-principal-component QTLs (pcQTLs). pcQTL discovery and fine-mapping used SuSiE and TensorQTL permutation-based FDR to identify an average of ~1,396 pcQTLs per tissue, ~27% of which were not found by single-gene eQTL mapping. pcQTLs tend to represent smaller effects distributed across multiple genes in a cluster and often colocalize with GWAS hits missed by single-gene methods. Functionally, pcQTLs increased GWAS colocalizations by 33%, highlighting multi-gene regulatory proxitropy as a source of complex-trait-associated variation.

Conclusion:
Cis-multi-gene pcQTL mapping uncovers novel regulatory loci and increases GWAS colocalizations compared with single-gene analyses, demonstrating that multi-gene approaches improve detection and interpretation of complex-trait-associated variants.

Music:
Enjoy the music based on this article at the end of the episode.

Article title:
Focus on single-gene effects limits discovery and interpretation of complex-trait-associated variants

First author:
Lawrence

Journal:
The American Journal of Human Genetics

DOI:
10.1016/j.ajhg.2026.02.022

Reference:
Lawrence, K.A., Gjorgjieva, T., Nachun, D., and Montgomery, S.B. (2026). Focus on single-gene effects limits discovery and interpretation of complex-trait-associated variants. The American Journal of Human Genetics 113, 1–10. https://doi.org/10.1016/j.ajhg.2026.02.022

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 – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00

Official website https://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/cis-pcqtl-allelic-proxitropy-gtex

QC:
This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-03-24.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Audited the transcript sections presenting the conceptual shift to neighborhood gene regulation (allelic proxytropy), the cis-pcQTL (pcQTL) methodology, GTEx tissue clustering, key quantitative results (novel pcQTLs, clusters, colocalizations), and concrete examples (HOXB cluster, IL-18 receptor genes), plus discussion
- transcript topics: Conceptual shift to gene neighborhoods and allelic proxytropy; cis-pcQTL (pcQTL) methodology and PCA-based signal extraction; GTEx tissue clusters and gene-neighborhood calling; pcQTL discovery statistics (clusters, pcQTLs per tissue, novel signals); pcQTLs and GWAS colocalizations; HOXB cluster example (HOXB3 vs HOXB4) and PC4

QC Summary:
- factual score: 10/10
- metadata score: 10/10
- supported core claims: 6
- 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:
- pcQTLs reveal novel multi-gene regulatory variants missed by single-gene eQTLs
- average pcQTLs per tissue is 1,396
- 27% of pcQTL signals are novel (4,859 pcQTLs)
- pcQTLs increase GWAS colocalizations by 33% vs single-gene QTLs
- HOXB cluster PC4 captures inverse variation between HOXB3 and HOXB4
- IL-18 receptor cluster (IL18RAP/IL18R1) pcQTL colocalizes with eczema, dermatitis, IBD

QC result: Pass.

Farnung J et al., Nature - Cryo-EM and biochemical reconstitution reveal how the ZSWIM8–CUL3 E3 ligase recognizes human AGO2–miRNA–trigger complexes to polyubiquitylate AGO and drive targeted microRNA degradation. Key terms: ZSWIM8, AGO2, target-directed miRNA degradation, cryo-EM structure, E3 ubiquitin ligase.

Study Highlights:
Using purified human proteins and cellular assays, the authors combined cryo-EM (3.1 Å), in vitro ubiquitylation, co-immunoprecipitation and sRNA-seq to dissect TDMD. Cryo-EM shows a dimeric ZSWIM8 that forms an asymmetric clamp around AGO2–miR-7–CYRANO, engaging the MID, N and PAZ domains and embracing trigger RNA flanks. Biochemical reconstitution demonstrates that ZSWIM8–CUL3 together with ARIH1 polyubiquitylates surface lysines of AGO only when the miRNA is paired to a trigger that vacates the PAZ pocket and imposes a specific RNA trajectory. Functionally, these multivalent RNA–RNA, RNA–protein and protein–protein interactions establish a two-RNA-factor authentication mechanism that explains TDMD selectivity and indicates ZSWIM8 can destabilize extensively trimmed miRNAs.

Conclusion:
ZSWIM8–CUL3 recognizes a trigger-induced AGO–miRNA conformation via multivalent interactions—including sensing a vacated PAZ pocket and flanking trigger RNA—to direct ARIH1-dependent polyubiquitylation of AGO and execute TDMD.

Music:
Enjoy the music based on this article at the end of the episode.

Article title:
The E3 ubiquitin ligase mechanism specifying targeted microRNA degradation

First author:
Farnung J

Journal:
Nature

DOI:
10.1038/s41586-026-10232-0

Reference:
Farnung J., Slobodyanyuk E., Wang P.Y., Blodgett L.W., Lin D.H., von Gronau S., Schulman B.A. & Bartel D.P. The E3 ubiquitin ligase mechanism specifying targeted microRNA degradation. Nature (2026). https://doi.org/10.1038/s41586-026-10232-0

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 – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00

Official website https://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/zswim8-cul3-tdmd-structure

QC:
This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-03-23.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Audited the transcript portions describing TDMD mechanism, ZSWIM8–CUL3 E3 ligase architecture, AGO2–miRNA–trigger complex recognition, CYRANO/HSUR1 triggers, RNA flanking regions and RBEs, PAZ-pocket vacancy, dimeric clamp, and broader biological implications.
- transcript topics: TDMD overview and cellular context; ZSWIM8–CUL3 E3 ligase architecture and dimer clamp; AGO2–miRNA–trigger complex recognition by ZSWIM8; Trigger RNAs (CYRANO, HSUR1) and pairing architecture; RNA flanking regions and RBEs in ZSWIM8 binding; PAZ pocket vacancy and RNA trajectory

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:
- TDMD is mediated by ZSWIM8–CUL3 E3 ligase polyubiquitylating AGO2–miRNA in the presence of a trigger RNA
- ZSWIM8 preferentially binds AGO–miRNA–trigger ternaries over AGO–miRNA–seed-only complexes
- ZSWIM8 operates as a dimer that clamps around the AGO2–miR-7–CYRANO complex
- Trigger RNA-induced conformational changes expose an unoccupied PAZ pocket that is recognized by ZSWIM8
- RNA flanking regions and RBEs contribute to ZSWIM8 recognition and binding efficiency
- Two-RNA-factor authentication model: miRNA as password, trigger RNA as phone ping

QC result: Pass.

Norgren J et al., JAMA Network Open - Population-based SNAC-K study finds higher meat consumption associated with slower cognitive decline and lower dementia risk in APOE ε3/ε4 and ε4/ε4 older adults. Key terms: APOE4, meat consumption, dementia, episodic memory, SNAC-K.

Study Highlights:
Using the Swedish National Study on Aging and Care–Kungsholmen (SNAC-K) cohort of older adults and repeated validated food-frequency questionnaires, the authors applied panel data analyses with linear regression for cognitive trajectories and Fine and Gray models for dementia incidence. Higher total meat consumption (top vs bottom quintile) in APOE ε3/ε4 and ε4/ε4 participants was associated with better 10-year global cognitive trajectories (β = 0.32) and lower dementia risk (sHR = 0.45). The processed-to-total meat ratio was associated with higher dementia risk (sHR = 1.14) without APOE interaction. Post hoc vitamin B12 analyses suggested APOE-specific differences in nutrient uptake that could help explain the genotype-specific associations.

Conclusion:
Higher meat consumption was associated with slower cognitive decline and reduced dementia incidence among APOE ε3/ε4 and ε4/ε4 carriers, such that the expected excess risk in these genotypes was not observed at high intake levels.

Music:
Enjoy the music based on this article at the end of the episode.

Article title:
Meat Consumption and Cognitive Health by APOE Genotype

First author:
Norgren J

Journal:
JAMA Network Open

DOI:
10.1001/jamanetworkopen.2026.6489

Reference:
Norgren J, Carballo-Casla A, Grande G, et al. Meat Consumption and Cognitive Health by APOE Genotype. JAMA Network Open. 2026;9(3):e266489. https://doi.org/10.1001/jamanetworkopen.2026.6489

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 – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00

Official website https://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/meat-apoe34-44-cognition

QC:
This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-03-22.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Audited the transcript’s representation of the paper’s core scientific claims: APOE4 carriers (APOE34/44) show cognitive benefits and reduced dementia risk with higher meat intake; non-APOE34/44 show no such association; processed meat increases dementia risk; unprocessed meat associates with lower mortality in APOE34/
- transcript topics: APOE gene and Alzheimer's risk; APOE4 vs APOE3/2 evolution and dietary adaptation; SNAC-K cohort design, dietary assessment, and cognitive outcomes; Total meat intake and cognitive trajectories by APOE genotype; Dementia incidence by APOE genotype and meat quintiles; Processed-to-total meat ratio and dementia risk

QC Summary:
- factual score: 10/10
- metadata score: 10/10
- supported core claims: 6
- 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:
- APOE34/44 carriers show improved cognitive trajectories and reduced dementia risk with higher meat intake (top quintile) compared with bottom quintile.
- Cognition and dementia benefits for APOE34/44 are quantified as β = 0.32 (P = .01) and sHR = 0.45 (P = .04) respectively.
- No cognitive or dementia associations with meat intake in non-APOE34/44 genotypes (APOE22/23/24/33).
- A higher processed-to-total meat ratio is unfavorably associated with dementia (sHR = 1.14; P = .04) with no APOE interaction.
- Post hoc analyses: unprocessed meat linked to lower all-cause mortality in APOE34/44 (HR = 0.85; P = .04; P for interaction = .03).
- Vitamin B12 absorption differences via food matrix proposed as a mechanism; APOE4 may absorb more from meat matrix than from other sources.

QC result: Pass.

Johnson MB et al., The American Journal of Human Genetics - Bi-allelic variants in snRNAs RNU6ATAC and RNU4ATAC cause infancy-onset autoimmune diabetes in humans, with RNA-seq showing U12 intron retention and impaired B cell development. Key terms: RNU6ATAC, RNU4ATAC, minor spliceosome, U12 intron retention, autoimmune diabetes.

Study Highlights:
In human infants with early-onset diabetes and immune dysregulation, the authors used genome sequencing, RNA-seq, DNA methylation deconvolution, WGCNA, Sanger sequencing, and flow cytometry to define a genetic syndrome. They identified 19 individuals with bi-allelic RNU6ATAC or RNU4ATAC variants and RNA-seq revealed significant U12 intron retention in 274 genes, 94% of which are known U12-intron-containing genes. Multi-omic analyses and targeted immune profiling showed reduced naive B cells and abnormal B cell maturation. Half of tested individuals were GADA-positive, supporting an autoimmune mechanism for the diabetes in these snRNA spliceosome disorders.

Conclusion:
Bi-allelic pathogenic variants in RNU6ATAC cause early-onset autoimmune diabetes with immune dysregulation and bi-allelic RNU4ATAC variants extend RNU4ATAC-opathy to include infancy-onset autoimmune diabetes.

Music:
Enjoy the music based on this article at the end of the episode.

Article title:
Bi-allelic variants in the non-protein-coding minor spliceosome components RNU6ATAC and RNU4ATAC cause syndromic monogenic autoimmune diabetes

First author:
Johnson MB

Journal:
The American Journal of Human Genetics

DOI:
10.1016/j.ajhg.2026.02.017

Reference:
Johnson MB, Russ-Silsby J, Blair PA, Govier M, Bonfield G, Domingo-Vila C, EXE-T1D consortium, ATAC clinical consortium, Wakeling MN, Oram RA, Flanagan SE, Tree TIM, Patel KA, Hattersley AT, De Franco E. Bi-allelic variants in the non-protein-coding minor spliceosome components RNU6ATAC and RNU4ATAC cause syndromic monogenic autoimmune diabetes. The American Journal of Human Genetics. 2026 Apr 2;113:1–11. https://doi.org/10.1016/j.ajhg.2026.02.017

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 – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00

Official website https://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/rnu6atac-rnu4atac-minor-spliceosome

QC:
This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-03-22.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Audited the transcript portions describing (a) minor spliceosome biology and snRNA function, (b) genetic findings in RNU6ATAC and RNU4ATAC, (c) U12 intron retention as a shared mechanism, (d) B cell development impairment and multi-omic immune profiling, (e) autoimmunity evidence (GADA positivity), (f) clinical phenoty
- transcript topics: Minor spliceosome biology and U12 introns; RNU6ATAC bi-allelic variants; RNU4ATAC bi-allelic variants and interaction with RNU6ATAC; RNA-seq intron retention in U12 genes; B cell development and maturation defects; Islet autoantibody positivity in early-onset diabetes

QC Summary:
- factual score: 10/10
- metadata score: 10/10
- supported core claims: 6
- 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:
- 19 individuals from 16 families with bi-allelic variants in RNU6ATAC or RNU4ATAC
- RNA-seq shows U12 intron retention in 274 genes (274/258 known U12 genes; 94% overlap with IAOD)
- 50% of tested individuals were GADA-positive
- Reduced naive B cells and impaired B cell maturation validated by DNA methylation deconvolution and flow cytometry
- Infancy-onset insulin-dependent diabetes (median onset ~17–20 weeks)

QC result: Pass.

Koga T et al., Nature Astronomy - Ryugu asteroid samples analyzed by HPLC/ESI-HRMS reveal all five canonical nucleobases (adenine, guanine, cytosine, thymine, uracil) and distribution linked to ammonia. Key terms: Ryugu, nucleobases, adenine, HPLC/ESI-HRMS, purine-to-pyrimidine ratio.

Study Highlights:
The team analysed Ryugu aggregate samples A0480 and C0370 and the Orgueil meteorite using water and HCl extraction followed by HPLC/ESI-HRMS, CE-HRMS and nano-EA/IRMS. They identified all five canonical nucleobases and measured total nucleobase concentrations (C0370 = 1,577 pmol g−1) and purine-to-pyrimidine (Pu/Py) ratios of ~1.1–1.2 in Ryugu contrasted with 0.099 in Orgueil and 3.4 in Murchison. A strong negative correlation (R2=0.89) between Pu/Py ratios and ammonia across Ryugu, Bennu and Orgueil implies ammonia availability influenced nucleobase formation pathways. The results support widespread abiotic nucleobase synthesis in carbonaceous parent bodies and potential delivery of diverse prebiotic molecules to early Earth.

Conclusion:
All five canonical nucleobases are present in Ryugu samples and their purine-to-pyrimidine distributions, which correlate with ammonia, indicate shared but environment-dependent formation pathways on carbonaceous parent bodies.

Music:
Enjoy the music based on this article at the end of the episode.

Article title:
A complete set of canonical nucleobases in the carbonaceous asteroid (162173) Ryugu

First author:
Koga T

Journal:
Nature Astronomy

DOI:
10.1038/s41550-026-02791-z

Reference:
Koga T., Ogawa N. O., Ohkouchi N., Oba Y., Takano Y., Naraoka H., Sasaki K., Sato H., Yoshimura T. et al. A complete set of canonical nucleobases in the carbonaceous asteroid (162173) Ryugu. Nature Astronomy (2026). https://doi.org/10.1038/s41550-026-02791-z

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 – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00

Official website https://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/ryugu-nucleobases-ammonia-correlation

QC:
This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-03-20.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Audited transcript sections presenting nucleobase detection, extraction/analytical workflow, concentration data for Ryugu samples, Pu/Py ratios across samples, ammonia correlation, abiotic/isomer evidence (6-methyluracil, hypoxanthine isomer), Chargaff's rule discussion, isotopic signatures, contamination controls, and
- transcript topics: Detection of all five canonical nucleobases in Ryugu; Sequential extraction workflow (water then HCl) and analytical methods (HPLC/ESI-HRMS, CE-HRMS, nano-EA/IRMS); Concentrations of nucleobases in Ryugu samples A0480 and C0370; comparison to Orgueil; Pu/Py (purine/pyrimidine) ratios across Ryugu, Bennu, Orgueil, and Murchison; Correlation between Pu/Py ratios and ammonia concentrations; Evidence for abiotic nucleobase formation: non-biological isomers (6-methyluracil) and hypoxanthine isomer

QC Summary:
- factual score: 10/10
- metadata score: 10/10
- supported core claims: 6
- 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:
- All five canonical nucleobases detected in Ryugu samples A0480 and C0370 (adenine, guanine, cytosine, thymine, uracil).
- Total nucleobase concentration in C0370: 1577 ± 35 pmol g−1; in A0480: 507 ± 21 pmol g−1.
- Pu/Py ratios: Ryugu A0480 ≈ 1.1–1.2; Ryugu C0370 ≈ 1.1–1.2; Orgueil ≈ 0.099; Bennu ≈ 0.55; Murchison ≈ 3.4.
- Pu/Py ratio negatively correlates with ammonia across Ryugu, Bennu, Orgueil (R2 ≈ 0.89).
- Detection of non-biological isomers (e.g., 6-methyluracil) and an hypoxanthine isomer.
- Isotopic signatures show heavy isotopes (δ13C and δ15N) in soluble components, supporting a space origin.

QC result: Pass.

Amour C et al., Human Genetics and Genomics Advances, Journal Pre-proof - Sex-stratified cQTL mapping in Tanzanian and Dutch adults identifies sex-specific regulators such as TOX-linked IFN-γ in males and EGFR-linked IL-10 in females, revealing multiple genome-wide cQTLs. Key terms: TOX, EGFR, cytokine QTL, sex-stratified GWAS, Tanzania-Netherlands.

Study Highlights:
The study analyzed cytokine production after ex vivo stimulation in two human cohorts (Tanzania 300TZFG and Dutch 500FG) using sex-stratified cytokine QTL mapping with linear models adjusted for cell counts and covariates. Genotyping, imputation, ELISA cytokine assays, colocalization (coloc) and SNP×sex interaction tests were applied to test sex-specific genetic effects. The authors report twelve genome-wide significant cQTLs in the Tanzanian cohort (seven male-specific, five female-specific) and twelve in the Dutch cohort with multiple sex-specific loci, highlighting TOX-associated IFN-γ regulation in males and EGFR-linked IL-10 regulation in females. These sex-specific autosomal effects altered which associations were detectable in pooled analyses, implying implications for sex-aware precision approaches to immune-related diseases.

Conclusion:
Sex-stratified autosomal analyses identify distinct genetic regulators of cytokine production, demonstrating that many cQTLs act in a sex-specific manner across Tanzanian and Dutch cohorts and can be missed by pooled analyses.

Music:
Enjoy the music based on this article at the end of the episode.

Article title:
Sex-stratified genetic regulators of cytokine production in the Dutch and Tanzanian populations

First author:
Amour C

Journal:
Human Genetics and Genomics Advances, Journal Pre-proof

DOI:
10.1016/j.xhgg.2026.100593

Reference:
Amour C, Cetatean R, Ponce IR, Keur N, Temba GS, Kullaya VI, Mmbaga BT, Kavishe R, Joosten LAB, Netea MG, de Mast Q, Boahen CK, Kumar V, Sex-stratified genetic regulators of cytokine production in the Dutch and Tanzanian populations, Human Genetics and Genomics Advances (2026), doi: https://doi.org/10.1016/j.xhgg.2026.100593.

License:
Not specified in the provided text.

Support:
Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00

Official website https://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/sex-stratified-cytokine-qtl

QC:
This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-03-19.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Audited the transcript sections describing (1) Tanzanian cohort results (12 cQTLs; 7 male-specific, 5 female-specific), (2) Dutch cohort results (12 cQTLs; 6 male-specific, 6 female-specific), (3) exemplar sex-specific loci TOX (male IFN-γ) and EGFR (female IL-10), (4) CNTNAP2 and ANXA8 findings, (5) colocalization ana
- transcript topics: Sex differences in immune regulation and cytokine signaling; Cohort design: Tanzanian (TZ) and Dutch (NL) sex-stratified cQTL mapping; TOX locus and IFN-γ response in males (S. pneumoniae); EGFR locus and IL-10 response in females (C. burnetii); CNTNAP2 locus and IFN-γ response in females (M. tuberculosis).; ANXA8 locus and TNF-α response in females (C. albicans)

QC Summary:
- factual score: 10/10
- metadata score: 10/10
- supported core claims: 6
- 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:
- Two cohorts: Tanzania TZFG and Netherlands 500FG (Dutch) with sex-stratified cQTL mapping
- Tanzanian cohort identified 12 genome-wide significant cQTLs (7 male-specific, 5 female-specific)
- Dutch cohort identified 12 genome-wide significant cQTLs (6 male-specific, 6 female-specific)
- TOX locus variant rs10092649 associated with IFN-γ production after S. pneumoniae stimulation in males
- EGFR-proximal locus rs79030770 associated with IL-10 production after C. burnetii stimulation in females
- CNTNAP2 locus variant rs17170577 associated with IFN-γ production after M. tuberculosis stimulation in females

QC result: Pass.

Fortuno C et al., Human Genetics and Genomics Advances - TP53 germline variant analysis using functional assays finds reduced-penetrance variants have intermediate activity, higher frequency, later onset, and 106 predicted candidates. Key terms: TP53, reduced penetrance, Li-Fraumeni syndrome, functional assays, variant interpretation.

Study Highlights:
Using ClinVar curation and comparison to benign and pathogenic reference sets, the authors analyzed TP53 germline variants with multiple functional assays, bioinformatic predictors, immune-fitness scores, and gnomAD frequencies. Reduced-penetrance variants tended to show intermediate activity across Kato, Giacomelli, Kotler, and Funk assays and intermediate BayesDel/AlphaMissense/aGVGD scores, with higher allele frequencies than pathogenic variants. A random forest model trained on these features prioritized 106 additional ClinVar missense variants as potential reduced-penetrance candidates. Clinically, carriers of reduced-penetrance variants exhibited later average age at first cancer and weaker enrichment for core Li-Fraumeni phenotypes, supporting consideration of attenuated surveillance criteria.

Conclusion:
Reported reduced-penetrance TP53 variants display intermediate functional and bioinformatic signatures, higher population frequency, and later cancer onset, and a combined-feature predictive model identifies additional candidate reduced-penetrance variants for follow-up.

Music:
Enjoy the music based on this article at the end of the episode.

Article title:
Characteristics predicting reduced penetrance variants in the high-risk cancer predisposition gene TP53

First author:
Fortuno C

Journal:
Human Genetics and Genomics Advances

DOI:
10.1016/j.xhgg.2025.100484

Reference:
Fortuno C, Richardson ME, Pesaran T, McGoldrick K, James PA, Spurdle AB. Characteristics predicting reduced penetrance variants in the high-risk cancer predisposition gene TP53. Human Genetics and Genomics Advances. 2025;6:100484. https://doi.org/10.1016/j.xhgg.2025.100484

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 – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00

Official website https://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-reduced-penetrance-prediction

QC:
This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-03-18.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Audited sections describing TP53 reduced-penetrance variants, four functional assays (Kato, Giacomelli, Kotler, Funk), bioinformatic predictors (BayesDel, AlphaMissense, aGVGD), immune fitness, population allele frequency, a random forest model identifying additional candidates, and associated clinical implications.
- transcript topics: TP53 and Li-Fraumeni syndrome background; Functional assays (Kato, Giacomelli, Kotler, Funk); Bioinformatic predictors (BayesDel, AlphaMissense, aGVGD); Immune fitness predictions; Population allele frequency (gnomAD); Random forest model and variant prioritization

QC Summary:
- factual score: 10/10
- metadata score: 10/10
- supported core claims: 6
- 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:
- Reduced penetrance TP53 variants show intermediate functional activity across four assays (Kato, Giacomelli, Kotler, Funk).
- Brazilian founder TP53 variant c.1010G>A (p.R337H) is discussed among the reduced penetrance set.
- Benign reference set (62 variants) and pathogenic reference set (113 variants) used for comparison; 11 reduced penetrance variants identified from ClinVar/other sources.
- Four functional assays (Kato, Giacomelli, Kotler, Funk) with intermediate results for reduced penetrance variants.
- Bioinformatic predictors (BayesDel, AlphaMissense, aGVGD) predict deleterious effects for reduced penetrance variants with lower scores than pathogenic variants.
- Immune fitness indicates intermediate visibility of reduced penetrance variants—between benign and pathogenic.

QC result: Pass.

Mendez R et al., Human Genetics and Genomics Advances, Journal Pre-proof - Biallelic RNU6ATAC variants disrupt the U6atac minor spliceosomal snRNA, causing transcriptome-wide minor intron retention and short stature with variable multisystem manifestations. Key terms: RNU6ATAC, U6atac, minor spliceosome, minor intron retention, whole-genome sequencing.

Study Highlights:
This study analyzed three unrelated human individuals using RNA-seq on whole-blood and fibroblasts and applied a FRASER-based minor intron retention (MIR) outlier pipeline alongside whole-genome sequencing. The integrated approach identified biallelic RNU6ATAC variants that map to U4atac–U6atac Stem I/II and the central stem-loop of U6atac. Affected individuals show transcriptome-wide excess MIR (for example A1 exhibited 254 MIR outliers in whole blood and B1 exhibited 16 MIR outliers in fibroblasts), indicating impaired minor spliceosome function. The molecular defect correlates with impaired growth and variable multisystem phenotypes including immunodeficiency and neurodevelopmental involvement.

Conclusion:
Biallelic RNU6ATAC variants cause a multisystem minor spliceopathy defined by transcriptome-wide minor intron retention and variable short stature, immunologic, and neurodevelopmental manifestations.

Music:
Enjoy the music based on this article at the end of the episode.

Article title:
Biallelic Variants in RNU6ATAC Result in a Minor Spliceopathy Characterized by Transcriptome-Wide Minor Intron Retention Events and Short Stature with Variable Multisystem Manifestations

First author:
Mendez R

Journal:
Human Genetics and Genomics Advances, Journal Pre-proof

DOI:
10.1016/j.xhgg.2026.100588

Reference:
Mendez R, Arriaga TM, Ma J, Bonner DE, Emami S, Levy RJ, Alsagheir A, Alhaddad B, Bakur K, Ungar RA, Matalon DR, Miller AM, Nguyen J, Smith KS, Scott SA, Liao L, Ng Z, Marwaha S, Ward A, Undiagnosed Diseases Network, Genomics Research to Elucidate the Genetics of Rare Diseases Consortium, Novacic D, Alkuraya FS, Bernstein JA, Ganesh VS, O’Donnell-Luria A, Montgomery SB, Wheeler MT, Biallelic Variants in RNU6ATAC Result in a Minor Spliceopathy Characterized by Transcriptome-Wide Minor Intron Retention Events and Short Stature with Variable Multisystem Manifestations, Human Genetics and Genomics Advances (2026), doi: https://doi.org/10.1016/j.xhgg.2026.100588

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 – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00

Official website https://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/rnu6atac-minor-spliceopathy

QC:
This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-03-18.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Audited transcript sections describing MIR as a transcriptome-wide effect, structural disruption of U4atac–U6atac, FRASER MIR filtering, need for WGS over WES, CADD/conservation evidence, tissue-specific effects, and the bridging C1 phenotype.
- transcript topics: Minor intron retention (MIR) and transcriptome-wide MIR pattern; RNU6ATAC structural disruption (Stem I/II and central stem-loop); FRASER MIR outlier analysis and tissue specificity; Whole-genome sequencing vs whole-exome sequencing; CADD scores and evolutionary conservation; Clinical bridging phenotype (A1, B1, C1) and spectrum of RNU6ATAC-opathy

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:
- Three unrelated individuals with biallelic RNU6ATAC variants
- A1: 254 MIR outliers in whole blood; B1: 16 MIR outliers in fibroblasts
- Variants localize to U4atac–U6atac Stem I/II and central stem-loop regions
- WGS was necessary because RNU6ATAC is not targeted by standard WES kits
- RNU6ATAC variants yield CADD scores between 18 and 21
- Conservation across vertebrates, including zebrafish

QC result: Pass.