8: A structural variation reference for medical and population genetics

Collins RL et al et al., Nature - This episode reviews gnomAD-SV, a sequence-resolved reference of structural variants from 14,891 genomes that catalogs 433,371 SVs (335,470 high-quality) and integrates the resource into the gnomAD browser for population and clinical use. Key terms: structural variants, gnomAD-SV, whole-genome sequencing, dosage sensitivity, population genetics.

Study Highlights:
The authors built gnomAD-SV from high-coverage whole-genome sequencing across diverse populations and discovered a complex landscape of hundreds of thousands of SVs. They estimate SVs contribute about 25–29% of rare protein-truncating events per genome and show strong concordance between selection on damaging SNVs and rare gene-altering SVs. Noncoding CNVs show modest but widespread selection correlated with sequence conservation. The resource identifies very large rare SVs in a few percent of individuals and flags ~0.13% of people with SVs meeting existing criteria for clinically actionable incidental findings.

Conclusion:
gnomAD-SV provides a public, high-coverage reference of sequence-resolved structural variation that improves interpretation of SVs in population genetics, GWAS, and clinical whole-genome sequencing while noting short-read WGS underestimates some repeat-mediated and complex SV classes.

QC:
This episode was checked against the original article PDF and publication metadata for the episode release published on 2025-04-17.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music

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:
- The episode reports that the gnomAD-SV study analyzed 14,891 genomes with an average coverage of 32×.
- The study discovered 433,371 SVs, with 335,470 high-quality SVs and a median of 7,439 SVs per genome.
- Structural variants contribute ~25–29% of all rare protein-truncating events per genome.
- 0.13% of individuals carry an SV meeting ACMG incidental findings criteria.
- Approximately 3.8% of individuals carry at least one very large (≥1 Mb) rare autosomal SV.
- An example case of chromothripsis-like rearrangement was found in a healthy adult.

QC result: Pass.