Gene Annotation


What are RefSeq Numbers?
The Reference Sequence (RefSeq) collection aims to provide a comprehensive, integrated, non-redundant set of sequences, including genomic DNA, transcript (RNA), and protein products, for major research organisms.


RefSeq standards serve as the basis for medical, functional, and diversity studies; they provide a stable reference for gene identification and characterization, mutation analysis, expression studies, polymorphism discovery, and comparative analyses. RefSeqs are used as a reagent for the functional annotation of some genome sequencing projects, including those of human and mouse. (From NCBI)

Where do I find RefSeq Numbers?

Entrez Nucleotides database, in NCBI, is a collection of sequences from several sources, including GenBank, RefSeq, and PDB.

Human Gene Nomenclature (HGNC)
HGNC operates under the Human Genome Organization (HUGO) and provides unique and meaningful names and symbols to over 22,000 genes.

Mouse Genome Informatics (MGI)
MGI provides integrated access to data on the genetics, genomics, and biology of the laboratory mouse.

What is a gene accession number?
The accession number is the unique identifier assigned to the entire sequence record when the record is submitted to GenBank. The GenBank accession number is a combination of letters and numbers that are usually in the format of one letter followed by five digits (e.g., M12345) or two letters followed by six digits (e.g., AC123456).

Why can’t I find my gene using my gene symbol?
The symbol associated with your gene may have changed. We recommend you visit NCBI, HGNC, or MGI for symbol verification.

What is a TRC Number?
A unique number developed by The RNAi Consortium to identify the TRC Library. A TRC number begins with “TRCN” followed by 10 digits. (e.g. MISSION™ shRNA TRCN0000030720).

Contact Us
For questions about the library, pricing and quotes or other concerns, please e-mail us at:

MISSION is a registered trademark of Sigma-Aldrich Co. LLC Label License.

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