Genome Aggregation Database Version 4-Allele Frequency Changes and Impact on Variant Interpretation in Dystonia.

BACKGROUND

Population-scale databases majorly contribute to variant interpretation. The recently released Genome Aggregation Database (gnomAD) v4 offers a >5-fold increased sample size compared to v2.1.1. Pathogenic variants absent from v2.1.1 are now registered in v4 at a considerable rate. The implications on variant interpretation in dystonia are unknown.

METHODS

All curated variants linked to the most common dominant forms of isolated dystonia were extracted from the International Parkinson's Disease and Movement Disorder Society Gene database. We compared variant population-frequencies and gene constraint metrics between gnomAD v2.1.1 and v4.

RESULTS

The majority of dystonia-causing variants (192/247, 77.7%) remained absent from the newer gnomAD version. Of 219 variants absent from v2.1.1, 27 (12.3%) appeared for the first time in v4.1, including well-established pathogenic alleles. Gene constraints for GNAL and KMT2B significantly decreased in v4.

CONCLUSIONS

A growing number of dystonia-linked alleles are seen in gnomAD v4. The presence in population-scale data does not preclude pathogenicity. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.