The Reference Sequence Project

Prepared by Group 3

RefSeQ collection

1.

The RefSeq collection is unique in providing a curated, non-redundant, explicitly linked nucleotide and protein database representing significant taxonomic diversity. Genomic and protein sequence datasets are provided for the majority of organisms included; transcript records are currently provided for a subset of the eukaryotic collection.

2.

The RefSeq database provides a critical foundation for integrating sequence, genetic and functional information, and is used internationally as a standard for genome annotation. The collection is curated on an ongoing basis by collaborating groups and by NCBI staff. Sequence records are presented in a standard format and are subject to computational validation.

Distinction between genebank and refseq

RefSeq

RefSeq accession numbers are formatted as two alphabetic characters, followed by an underscore (‘_’), optionally followed by four alphabetic characters (specific to the NZ_ prefix), followed by six, eight or nine numerals.

Genebank

GenBank accessions never include an underscore. Different alphabetic prefixes have implied meaning in terms of both the process of generation and the type of molecule represented.

ANNOTATION PIPELINE

NCBI is providing annotation for some assembled genomic sequence data.
This pipeline is automated and data is refreshed periodically.
The model RefSeq records produced from this pipeline have a distinguishing accession prefix (XM, XR, XP), are derived from the genomic sequence

Model RefSeq

RNA and protein products that are generated by the eukaryotic genome annotation pipeline. (prefixes XM_, XR_, and XP_).

Known RefSeq

RNA and protein products that are mainly derived from GenBank cDNA and EST data and are supported by the RefSeq eukaryotic curation group. (prefixes NM_, NR_, and NP_).