RefSeq and LocusLink are two gene-centered resources provided by the National Center for Biotechnology Information (NCBI) to help researchers access comprehensive gene and sequence information. LocusLink organizes information around genes to provide a central hub for gene-specific data for species such as fruit fly, human, mouse, rat, and zebrafish. RefSeq provides reference sequence standards for genomes, transcripts, and proteins, with a focus on human, mouse, and rat mRNA sequences and their corresponding proteins. Together, these resources offer a non-redundant view of genes and other loci, supporting research on gene families, variation, expression, and genome annotation. LocusLink maintains descriptive information about genes, including nomenclature, disease associations, map positions, and sequence accessions. It links to other NCBI resources, such as GenBank, OMIM, and CDD, to facilitate navigation and discovery. LocusLink data are continuously updated through collaborations with various databases and organizations. It supports complex queries based on text terms, gene symbols, sequence accessions, and database IDs. RefSeq provides standards for complete genomic nucleic acids, assembled contigs, transcripts, and proteins. It includes non-redundant sequences derived from GenBank and literature. RefSeq records are linked to LocusLink and other resources, allowing access to additional information. RefSeq records are categorized into four types: genome annotation, predicted, provisional, and reviewed. Reviewed records are individually reviewed and annotated by NCBI staff. RefSeq and LocusLink have grown significantly over the past year, with RefSeq records tripling and LocusLink expanding fivefold. New records are made publicly available daily, and the LocusLink website is updated weekly. RefSeq and LocusLink provide essential resources for gene research, including sequence data, functional annotations, and links to other databases.RefSeq and LocusLink are two gene-centered resources provided by the National Center for Biotechnology Information (NCBI) to help researchers access comprehensive gene and sequence information. LocusLink organizes information around genes to provide a central hub for gene-specific data for species such as fruit fly, human, mouse, rat, and zebrafish. RefSeq provides reference sequence standards for genomes, transcripts, and proteins, with a focus on human, mouse, and rat mRNA sequences and their corresponding proteins. Together, these resources offer a non-redundant view of genes and other loci, supporting research on gene families, variation, expression, and genome annotation. LocusLink maintains descriptive information about genes, including nomenclature, disease associations, map positions, and sequence accessions. It links to other NCBI resources, such as GenBank, OMIM, and CDD, to facilitate navigation and discovery. LocusLink data are continuously updated through collaborations with various databases and organizations. It supports complex queries based on text terms, gene symbols, sequence accessions, and database IDs. RefSeq provides standards for complete genomic nucleic acids, assembled contigs, transcripts, and proteins. It includes non-redundant sequences derived from GenBank and literature. RefSeq records are linked to LocusLink and other resources, allowing access to additional information. RefSeq records are categorized into four types: genome annotation, predicted, provisional, and reviewed. Reviewed records are individually reviewed and annotated by NCBI staff. RefSeq and LocusLink have grown significantly over the past year, with RefSeq records tripling and LocusLink expanding fivefold. New records are made publicly available daily, and the LocusLink website is updated weekly. RefSeq and LocusLink provide essential resources for gene research, including sequence data, functional annotations, and links to other databases.