Variants are annotated using multiple reference databases including dbNSFP, ClinVar, dbSNP, dbscSNV, gnomAD, and the 1000 Genomes Project. Together, these resources provide information on known variants, population allele frequencies, clinical significance, functional predictions, and splice-site impact. This comprehensive annotation framework helps prioritize potentially pathogenic variants and distinguish rare disease-associated variants from common benign polymorphisms.