Performance comparison of germline variant calling tools in sporadic disease cohorts

Accurate variant calling is essential for next-generation sequencing (NGS)-based diagnosis of rare diseases, yet most benchmarking studies have focused on standard cell lines or trio-based samples, with limited relevance to sporadic cases. Here, we systematically compared the performance of DeepVariant and GATK HaplotypeCaller in two Chinese cohorts of patients with sporadic epilepsy (EP) and autism spectrum disorder (ASD). DeepVariant exhibited higher precision and sensitivity in detecting single nucleotide variants (SNVs), while GATK showed a distinct advantage in identifying rare variants, which are often key to understanding the genetic basis of rare diseases. Comparative analyses based on disease-related gene panels further highlighted differences in the identification of potentially deleterious variants. These findings reveal important trade-offs between variant callers and emphasize the need to tailor variant-calling strategies to specific research and clinical contexts. Our study provides practical vision for optimizing germline variant detection pipelines in sporadic neurodevelopmental disorders, offering broader insights for precision medicine applications.