RefSeq release 233 is now available online and from the FTP site! You can access RefSeq data through NCBI Datasets. The release is provided in several directories as a complete dataset and also as divided by logical groupings.   

As of January 26, 2026, this full release incorporates genomic, transcript, and protein data containing:  

• 578,285,616 records 
• 442,943,508 proteins 
• 76,278,418 RNAs 
• Sequences from 174,157 organisms 

 This release contains new or updated annotations generated by NCBI’s eukaryotic genome annotation pipeline for 63 species, including: 

• Rhesus macaque, based on updated T2T assembly T2T-MMU8v2.0 (GCF_049350105.2-RS_2025_08) 
• White-tufted-ear marmoset, (pictured) based on new near-T2T assembly calJac240_pri (GCF_049354715.1-RS_2025_12)  
• Thirteen-lined ground squirrel, based on new assembly mIctTri1.hap1 (GCF_052094955.1-RS_2025_11) 
• Spotted hyena, based on new assembly BGI_CrCroc_1.0 (GCF_008692635.1-RS_2025_11) 
• Girdled pipefish, based on new assembly RoL_Fcin_1.0 (GCF_051991245.1-RS_2025_11) 
• Sea squirt, based on updated assembly ASM1832782v2 (GCF_018327825.1-RS_2026_01) 
• Wolffia australiana, the world’s smallest flowering plant, based on new assembly ASM2967742v1 (GCF_029677425.1-RS_2025_12) 

 In the previous release, we updated 95 RefSeq assemblies (from Candida albicans, Candidozyma auris, Aspergillus, and Saccharomycetes) with functional protein annotation and gene symbols, improving thousands of records. Functional annotation was updated based on a new protein name and gene symbol assignment pipeline in RefSeq.  

We also updated the RefSeq assembly Aspergillus fumigatus Af293 with structural annotation and gene symbols from VEuPathDB. Functional protein annotation was updated based on the new functional annotation pipeline in RefSeq.  

We added a new RefSeq assembly for the widely used research strain Talaromyces marneffei ATCC18224 and computed improved functional annotation and gene symbols. 

More updates are planned for key RefSeq assemblies and with a focus on assemblies from pathogens and related species. 

 Several dozen RefSeqs have been created for viruses of a variety of organisms including mammals, insects, and bacteria. These RefSeqs are based on species exemplars from the ICTV’s Virus Metadata Resource (VMR_MSL39_v2). Additional virus RefSeqs will be created over the next several months. 

A new version (v1.5) of Matched Annotation from NCBI and EMBL-EBI (MANE) is now available. This dataset, produced in collaboration with the European Molecular Biology Laboratory’s European Bioinformatics Institute (EMBL-EBI), includes a total of 19,437 MANE Select transcripts for 19,367 protein-coding and 70 non-coding genes. There are also MANE Plus Clinical transcripts for 73 genes. 

RefSeq is part of the NIH Comparative Genomics Resource (CGR). CGR facilitates reliable comparative genomics analyses for all eukaryotic organisms through an NCBI Toolkit and community collaboration.  

Please reach out to us if you have questions or would like to provide feedback!