Base by Base

Gustavo Barra
  • 5,0 (1)
  • CIÊNCIAS DA VIDA
  • DIÁRIO

Base by Base explores advances in genetics and genomics, with a focus on gene-disease associations, variant interpretation, protein structure, and insights from exome and genome sequencing. Each episode breaks down key studies and their clinical relevance—one base at a time. Powered by AI, Base by Base offers a new way to learn on the go. Special thanks to authors who publish under CC BY 4.0, making open-access science faster to share and easier to explore.

  1. HÁ 1 DIA

    313: Integrating Polygenic Risk Scores and Social Determinants of Health across Populations

    Cromer SJ et al., The American Journal of Human Genetics - This paper reviews polygenic risk scores (PRS) and social determinants of health (SDoH) and outlines best practices for integrating PRS and SDoH across diverse populations to improve prediction and equity. Study Highlights: This review focuses on human populations and uses conceptual frameworks, hypothetical population examples, and synthesis of methodological studies to evaluate PRS and SDoH integration. It summarizes methods for PRS construction and transferability, SDoH measurement at individual and area levels, and analytic approaches including interaction, mediation, and calibration. Quantitatively, the authors note substantial declines in PRS predictive accuracy when applied to genetically distinct populations (for example, African-ancestry performance often ~20–40% of European-derived PRS). The review highlights harmonization, population-specific calibration, and interdisciplinary teams as functional steps to improve predictive validity and reduce inequitable impacts. Conclusion: Integrating PRSs with carefully measured and harmonized SDoH across diverse populations requires population-aware conceptual frameworks, calibrated analytic methods, diverse datasets, and ethical safeguards to improve predictive validity and equity. Music: Enjoy the music based on this article at the end of the episode. Reference: Cromer SJ, Cobran EK, Iyer HS, Hysong MR, Vargas LB, Smith JL, Konigsberg IR, Bogumil D, Glover L, King G, PRIMED Consortium SDoH Working Group, Lange LA, Patel A, Wojcik G, Raffield L, Conti DV, et al. Incorporating polygenic risk scores and social determinants of health across populations: Considerations and best practices in research. The American Journal of Human Genetics. 2026;113:1–25. https://doi.org/10.1016/j.ajhg.2026.02.007 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 – 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/polygenic-risk-sdoh-harmonization

    25min

  2. HÁ 1 DIA

    312: Mfsd2a transports LPC to maintain epidermal linoleate pools and desquamation

    Wong BHH et al., PNAS - Mouse and human studies show the LPC transporter Mfsd2a enables plasma-derived LPC uptake into keratinocytes, preserving linoleate-rich phosphatidylcholine pools and promoting epidermal differentiation. Study Highlights: Using epidermis-specific (2aEpKO) and conventional (2aKO) Mfsd2a-deficient mice, lineage tracing, untargeted shotgun lipidomics, LightOx-LPC uptake assays, and primary human keratinocyte cultures, the authors mapped Mfsd2a expression to suprabasal/granular keratinocytes and demonstrated Mfsd2a-dependent uptake of plasma-derived LPC in vivo. Lipidomic quantification showed reductions in linoleate-containing phospholipids (PL-18:2 decreased ~15% in 2aEpKO and ~13% in 2aKO) and a marked loss of TAG-18:2 (−79% in 2aEpKO). Inducible epidermal Mfsd2a loss produced transient dermatitis, defective desquamation, retained lamellar bodies, and keratinocyte activation, while MFSD2A knockdown in human keratinocytes reduced LPC-driven differentiation. Functional rescue experiments in vitro revealed that LPC-18:1 and LPC-18:2 promote keratinocyte differentiation in an MFSD2A-dependent manner, linking plasma LPC uptake to epidermal lipid homeostasis and differentiation. Conclusion: Mfsd2a mediates uptake of plasma-derived LPC (notably LPC-18:2) into suprabasal keratinocytes to maintain linoleate-containing phospholipid pools and support keratinocyte differentiation and normal desquamation. Music: Enjoy the music based on this article at the end of the episode. Reference: Wong BHH, Behmoaras J, Chua AWC, Galam DLA, Tan BC, Torta F, Chin CF, Mishra K, Ding M, Silver DL. Mfsd2a is important for maintaining epidermal homeostasis. Proc. Natl. Acad. Sci. U.S.A. 2026 Feb 19;123(8):e2531159123. https://doi.org/10.1073/pnas.2531159123 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/mfsd2a-lpc-epidermal-homeostasis

    15min

  3. HÁ 2 DIAS

    311: mtG3PDH (GPO1) loss in Drosophila impairs mitochondrial ATP/O, O2 consumption, and ROS

    Herpe L et al., PNAS - CRISPR knockout of Drosophila mtG3PDH (GPO1) reduces ATP production by ~60% and O2 consumption by ~33%, lowering mitochondrial efficiency and ROS emission. Study Highlights: Using CRISPR/Cas9-generated GPO1 mutant Drosophila and isolated thoracic mitochondria, the authors combined enzymatic assays, ATP production and oxygen consumption measurements, and H2O2 emission assays to probe mtG3PDH function. Loss of mtG3PDH markedly reduced mtG3PDH enzymatic activity and drove a ~60% decrease in ATP production and ~33% decrease in O2 consumption, producing a pronounced drop in mitochondrial efficiency (ATP/O). mtG3PDH-linked ROS emission was also strongly reduced (~70%), reflecting diminished direct and reverse electron-transfer ROS generation. Functionally, GPO1 flies showed sharply reduced survival and severe climbing impairment, linking the bioenergetic defects to organismal outcomes. Conclusion: mtG3PDH is essential for mitochondrial bioenergetics and redox homeostasis in Drosophila, with GPO1 loss causing major decreases in ATP production, O2 consumption, mitochondrial efficiency, and mtG3PDH-linked ROS that correlate with reduced survival and locomotion. Music: Enjoy the music based on this article at the end of the episode. Reference: Herpe L, Aminot M, Pichaud N. When alternative becomes essential: The role of mitochondrial glycerol-3-phosphate dehydrogenase. Proc. Natl. Acad. Sci. U.S.A. 2026;123(9):e2535701123. https://doi.org/10.1073/pnas.2535701123 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/drosophila-mtg3pdh-gpo1

    42min

  4. HÁ 3 DIAS

    310: Infant gut microbiota restoration — maternal FMT, Bifidobacterium and Bacteroides recovery after C‑section

    Korpela K et al., Gut Microbes - Review finds maternal fecal microbiota transplantation and targeted probiotics can restore Bifidobacterium and Bacteroides after C‑section or intrapartum antibiotics, with breastfeeding aiding recovery. Study Highlights: This review focuses on term infants, particularly C‑section and intrapartum antibiotic–exposed neonates, synthesizing cohort and intervention data using 16S rRNA gene amplicon sequencing and metagenomic approaches. Maternal fecal microbiota transplantation (maternal FMT) shifted C‑section infants’ gut communities to resemble vaginally born infants and uniquely restored Bacteroidaceae, while a Bifidobacterium–Lactobacillus–FOS supplement increased bifidobacteria; vaginal seeding did not normalize overall gut composition. The authors link restoration of key taxa to potential reductions in risks such as allergy and overweight and emphasize breastfeeding as an essential adjunct to restoration strategies. Conclusion: Evidence supports action to address early-life gut microbiota disruption: probiotics and maternal FMT show promising restorative effects, but optimal, scalable solutions and long-term immune outcomes remain to be established. Music: Enjoy the music based on this article at the end of the episode. Reference: Korpela K, de Vos WM. Infant gut microbiota restoration: state of the art. Gut Microbes. 2022;14(1):e2118811. https://doi.org/10.1080/19490976.2022.2118811 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/maternal-fmt-bifidobacterium-restoration

    49min

  5. HÁ 5 DIAS

    309: LASI-DAD 2,680-sample WGS panel boosts LD maps, imputation, and PRS in Indian genomes

    Li Z et al., Human Genetics and Genomics Advances. 7 ( - LASI-DAD 30× whole-genome sequencing of 2,680 Indian participants produced a 69.5M-variant LD panel that improves genotype imputation accuracy and PRS performance for Indian populations. Study Highlights: Using 30× WGS of 2,680 LASI-DAD participants, the authors constructed an LD lookup panel (69.5 million variants), phased with Eagle2.4, and identified LD structure with LDetect and Big-LD. They compared regional varLD to 1000G super-populations and evaluated imputation with Minimac4 and meta-imputation against TOPMed and GAsP. LASI-DAD increased imputation accuracy (aggregated r2) by a mean 38% versus TOPMed and 27% versus GAsP across allele frequencies and improved PRS predictive performance by 2.1%–35.1% across traits and studies. Finer-scale stronger LD and regional LD differences in LASI-DAD translate into more accurate LD estimates and better imputation and PRS transferability for Indian sub-populations. Conclusion: LASI-DAD is the largest nationally representative Indian WGS reference panel to date and it improves LD estimation, genotype imputation accuracy, and PRS construction for Indian and South Asian populations. Music: Enjoy the music based on this article at the end of the episode. Reference: Li Z, Zhao W, Zhou X, Leung YY, Schellenberg GD, Wang L-S, Schönherr S, Forer L, Fuchsberger C, Dey S, Lee J, Smith JA, Dey AB, Kardia SLR. A reference panel for linkage disequilibrium and genotype imputation using whole-genome sequencing data from 2,680 participants across India. Human Genetics and Genomics Advances. 7 (2026) 100579. https://doi.org/10.1016/j.xhgg.2026.100579. 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/lasi-dad-india-reference-panel

    24min

  6. HÁ 6 DIAS

    308: PANDORA-seq reveals conserved rsRNA length shift and tsRNA/rsRNA aging cliff in mouse and human sperm

    Shi J et al., The EMBO Journal - PANDORA-seq profiling of mouse and human sperm heads identifies a conserved rsRNA length shift with age and a tsRNA/rsRNA 'aging cliff' that reprograms embryonic transcripts. Study Highlights: Using PANDORA-seq on C57BL/6J mouse sperm (intact and de-membranated heads) across five age groups and two independent human sperm cohorts, the authors identify a sharp tsRNA/rsRNA "aging cliff" in mice between 50–70 weeks and a head-specific rsRNA length shift. PANDORA-seq overcomes modification-induced detection bias to reveal increases in longer rsRNAs and decreases in shorter rsRNAs, particularly from 28S- and 18S-rRNAs, with parallel trends in human cohorts. Mitochondrial tsRNAs/rsRNAs in sperm heads, although low abundance, covary with genomic sncRNAs and help distinguish age groups. Transfection of age-mimicking tsRNA/rsRNA cocktails into mouse embryonic stem cells reprograms gene expression, upregulating metabolic and neurodegeneration-related pathways, providing a functional link to offspring phenotypes. Conclusion: PANDORA-seq uncovers a conserved, sperm head–specific rsRNA length shift and a tsRNA/rsRNA aging cliff in mice and humans, and age-mimicking sncRNA combinations can alter embryonic transcriptomes linked to metabolic and neurodegenerative pathways. Music: Enjoy the music based on this article at the end of the episode. Reference: Shi J, Zhang X, Cai C, Liu S, Yu J, James ER, et al. Conserved shifts in sperm small non-coding RNA profiles during mouse and human aging. The EMBO Journal. 2026;45(4):1362–1380. https://doi.org/10.1038/s44318-025-00687-8 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/sperm-rsrna-length-shift

    22min

  7. 4 DE MAR.

    307: SNIPE membrane nuclease cleaves phage λ DNA during ManYZ-mediated genome injection in Escherichia coli

    Saxton DS et al., Nature - In E. coli, the membrane-bound nuclease SNIPE directly cleaves incoming phage λ DNA during genome injection, blocking infection via ManYZ and tape-measure protein interactions. Study Highlights: In Escherichia coli, the membrane-anchored protein SNIPE was shown to block phage λ by directly cleaving DNA during genome injection. The authors combined radiolabelled 32P phage DNA assays, time-lapse CFP-ParB/ParS microscopy, TurboID proximity labelling and pBPA crosslinking to map SNIPE localization and interactions. They report that membrane-localized SNIPE requires a DUF4041 domain and a GIY-YIG nuclease domain to generate DNA fragments during injection, reducing CFP-ParB puncta ~30-fold and producing a smear of 32P-labelled fragments; an E414A nuclease mutant abolished activity. Functionally, SNIPE prevents λ replication and cell lysis and provides broad defence against many siphoviruses via interactions with ManYZ and phage tape-measure proteins. Conclusion: SNIPE is a membrane-localized bacterial defence protein that associates with ManYZ and phage tape-measure proteins to directly cleave incoming phage DNA during genome injection, thereby blocking infection. Music: Enjoy the music based on this article at the end of the episode. Reference: Saxton DS, DeWeirdt PC, Doering CR, Roney IJ & Laub MT. A membrane-bound nuclease directly cleaves phage DNA during genome injection. Nature. 2026. https://doi.org/10.1038/s41586-026-10207-1 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/snipe-membrane-nuclease-phage-injection

    28min

  8. 3 DE MAR.

    306: SAXO6 loss-of-function in photoreceptor cilia links a microtubule inner protein to late-onset retinal dystrophy

    Moye AR et al., The American Journal of Human Genetics - Biallelic loss-of-function variants in SAXO6, a microtubule inner protein of photoreceptor cilia, cause late-onset retinal dystrophy by destabilizing axonemal microtubules. Study Highlights: The study analyzed human patients with late-onset recessive retinal dystrophy and combined genetic sequencing (WES/WGS and long-read RNA) with high-resolution imaging and proteomics. Iterative ultrastructure expansion microscopy and immuno-gold TEM localized SAXO6 to specific microtubule doublets in photoreceptor connecting cilia and outer segments and to motile cilia in airway models. Cross-linking mass spectrometry on isolated bovine tracheal cilia detected an interaction between SAXO6 Mn-motif regions and α-tubulin (Lys370), supporting SAXO6 as a microtubule inner protein. Functionally, predicted null SAXO6 genotypes segregate with late-onset RP or cone-rod dystrophy, implicating MIP dysfunction in long-term photoreceptor stability. Conclusion: Biallelic loss-of-function variants in SAXO6 cause late-onset retinal dystrophy, likely by disrupting a microtubule inner protein that stabilizes photoreceptor axonemes. Music: Enjoy the music based on this article at the end of the episode. Reference: Moye AR, McCafferty CL, Lin S, Han JH, Dudakova L, Rodenburg K, Szabó V, Nagy ZZ, Zur D, Vajter M, Kousal B, Moulin AP, Graff-Meyer A, Roosing S, Mahroo OA, Arno G, Webster AR, Ben-Yosef T, Liskova P, Engel BD, Zobor D, Quinodoz M, Rivolta C. Loss-of-function variants in SAXO6, encoding a microtubule inner protein of photoreceptor cilia, cause a late-onset retinal dystrophy. The American Journal of Human Genetics. 2026 Mar 5;113:1–18. https://doi.org/10.1016/j.ajhg.2026.02.001 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/saxo6-photoreceptor-mip-retina

    25min
Ver tudo (315)

Sobre

Base by Base explores advances in genetics and genomics, with a focus on gene-disease associations, variant interpretation, protein structure, and insights from exome and genome sequencing. Each episode breaks down key studies and their clinical relevance—one base at a time. Powered by AI, Base by Base offers a new way to learn on the go. Special thanks to authors who publish under CC BY 4.0, making open-access science faster to share and easier to explore.

Informações

  • Criado por
    Gustavo Barra
  • Anos de atividade
    2025 - 2026
  • Episódios
    315
  • Classificação
    Livre
  • Copyright
    © Gustavo Barra
  • Site do podcast
    Base by Base