Unveiling the Landscape of Reportable Genetic Secondary Findings in the Spanish Population: A Comprehensive Analysis Using the Collaborative Spanish Variant Server Database

The escalating adoption of Next Generation Sequencing (NGS) in clinical diagnostics reveals genetic variations, termed secondary findings (SFs), with health implications beyond primary diagnoses. The Collaborative Spanish Variant Server (CSVS), a crowdsourced database, contains genomic data from more than 2100 unrelated Spanish individuals. Following the American College of Medical genetics (ACMG) guidelines, CSVS was analyzed, identifying pathogenic or likely pathogenic variants in 78 actionable genes (ACMG list v3.1) to ascertain SF prevalence in the Spanish population. Among 1129 samples, 60 reportable SFs were found in 5% of individuals, impacting 32 ACMG-listed genes, notably associated with cardiovascular disease (59.4%), cancer (25%), inborn errors of metabolism (6.3%), and other miscellaneous phenotypes (9.4%). The study emphasizes utilizing dynamic population databases for periodic SF assessment, aligning with evolving ACMG recommendations. These findings illuminate the prevalence of significant genetic variants, enriching understanding of secondary findings in the Spanish population.