Show Notes
Herger M et al., Cell Genomics - Herger et al. present a pooled prime editing platform in haploid human cells that installs and assays thousands of short variants in their endogenous context. Using surrogate targets, co-selection and stringent pegRNA filtering, negative and positive selection screens identify loss-of-function variants in SMARCB1 and MLH1, including non-coding ClinVar variants that alter splicing. Key terms: prime editing, variant functional screening, SMARCB1, MLH1, HAP1 cells.
Study Highlights:
The authors develop a lentiviral pooled prime editing (PE) platform in HAP1 cells incorporating surrogate target (ST) sequences and co-selection to enrich edited cells. They optimize pegRNA scaffold design and show that ST editing rates are a useful proxy to filter active pegRNAs from inactive ones. Negative (essentiality) and positive (6-thioguanine) selection screens reveal novel loss-of-function variants in SMARCB1 and MLH1 across coding and non-coding regions. Stringent pegRNA activity filtering and orthogonal validation are necessary to reduce false positives and negatives.
Conclusion:
Pooled prime editing with surrogate targets and co-selection can scalably reveal functional effects of coding and non-coding human variants in their native genomic context, but accurate scoring depends on pegRNA activity and validation; improvements in pegRNA design and prime editors should expand genome-wide applicability.
QC:
This episode was checked against the original article PDF and publication metadata.
Scope: article metadata and core scientific claims from the narration, excluding analogies, intro/outro, and music.
Factual QC score: 10/10.
Metadata QC score: 10/10.
Supported core claims: 8.
Claims flagged for review: 0.
Metadata checks passed: 4.
Metadata issues found: 0.
QC result: Pass.
Music:
Enjoy the music based on this article at the end of the episode.
Article title:
High-throughput screening of human genetic variants by pooled prime editing
First author:
Herger M
Journal:
Cell Genomics
DOI:
10.1016/j.xgen.2025.100814
Reference:
Herger M., Kajba C.M., Buckley M., Cunha A., Strom M., Findlay G.M. (2025). High-throughput screening of human genetic variants by pooled prime editing. Cell Genomics 5, 100814. https://doi.org/10.1016/j.xgen.2025.100814
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/
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