National Center for Biotechnology Information

Last updated
National Center for Biotechnology Information
Founded1988;32 years ago (1988)
Headquarters Bethesda, Maryland, U.S.
Coordinates 38°59′45″N77°05′56″W / 38.9959°N 77.0989°W / 38.9959; -77.0989 Coordinates: 38°59′45″N77°05′56″W / 38.9959°N 77.0989°W / 38.9959; -77.0989

The National Center for Biotechnology Information (NCBI) [1] [2] is part of the United States National Library of Medicine (NLM), a branch of the National Institutes of Health (NIH). The NCBI is located in Bethesda, Maryland and was founded in 1988 through legislation sponsored by Senator Claude Pepper.


The NCBI houses a series of databases relevant to biotechnology and biomedicine and is an important resource for bioinformatics tools and services. Major databases include GenBank for DNA sequences and PubMed, a bibliographic database for biomedical literature. Other databases include the NCBI Epigenomics database. All these databases are available online through the Entrez search engine. NCBI was directed by David Lipman, [2] one of the original authors of the BLAST sequence alignment program [3] and a widely respected figure in bioinformatics. He also led an intramural research program, including groups led by Stephen Altschul (another BLAST co-author), David Landsman, Eugene Koonin, John Wilbur, Teresa Przytycka, and Zhiyong Lu. David Lipman stood down from his post in May 2017. [4]


NCBI has had responsibility for making available the GenBank DNA sequence database since 1992. [5] GenBank coordinates with individual laboratories and other sequence databases such as those of the European Molecular Biology Laboratory (EMBL) and the DNA Data Bank of Japan (DDBJ). [5]

Since 1992, NCBI has grown to provide other databases in addition to GenBank. NCBI provides Gene, Online Mendelian Inheritance in Man, the Molecular Modeling Database (3D protein structures), dbSNP (a database of single-nucleotide polymorphisms), the Reference Sequence Collection, a map of the human genome, and a taxonomy browser, and coordinates with the National Cancer Institute to provide the Cancer Genome Anatomy Project. The NCBI assigns a unique identifier (taxonomy ID number) to each species of organism. [6]

The NCBI has software tools that are available through internet browsers or by FTP. For example, BLAST is a sequence similarity searching program. BLAST can do sequence comparisons against the GenBank DNA database in less than 15 seconds.

NCBI Bookshelf

The NCBI Bookshelf [7] is a collection of freely accessible, downloadable, on-line versions of selected biomedical books. The Bookshelf covers a wide range of topics including molecular biology, biochemistry, cell biology, genetics, microbiology, disease states from a molecular and cellular point of view, research methods, and virology. Some of the books are online versions of previously published books, while others, such as Coffee Break , are written and edited by NCBI staff. The Bookshelf is a complement to the Entrez PubMed repository of peer-reviewed publication abstracts in that Bookshelf contents provide established perspectives on evolving areas of study and a context in which many disparate individual pieces of reported research can be organized.[ citation needed ]

Basic Local Alignment Search Tool (BLAST)

BLAST is an algorithm used for calculating sequence similarity between biological sequences such as nucleotide sequences of DNA and amino acid sequences of proteins. [8] BLAST is a powerful tool for finding sequences similar to the query sequence within the same organism or in different organisms. It searches the query sequence on NCBI databases and servers and posts the results back to the person's browser in the chosen format. Input sequences to the BLAST are mostly in FASTA or Genbank format while output could be delivered in a variety of formats such as HTML, XML formatting, and plain text. HTML is the default output format for NCBI's web-page. Results for NCBI-BLAST are presented in graphical format with all the hits found, a table with sequence identifiers for the hits having scoring related data, along with the alignments for the sequence of interest and the hits received with analogous BLAST scores for these [9]


The Entrez Global Query Cross-Database Search System is used at NCBI for all the major databases such as Nucleotide and Protein Sequences, Protein Structures, PubMed, Taxonomy, Complete Genomes, OMIM, and several others. [10] Entrez is both an indexing and retrieval system having data from various sources for biomedical research. NCBI distributed the first version of Entrez in 1991, composed of nucleotide sequences from PDB and GenBank, protein sequences from SWISS-PROT, translated GenBank, PIR, PRF, PDB, and associated abstracts and citations from PubMed. Entrez is specially designed to integrate the data from several different sources, databases, and formats into a uniform information model and retrieval system which can efficiently retrieve that relevant references, sequences and structures. [11]


Gene has been implemented at NCBI to characterize and organize the information about genes. It serves as a major node in the nexus of the genomic map, expression, sequence, protein function, structure, and homology data. A unique GeneID is assigned to each gene record that can be followed through revision cycles. Gene records for known or predicted genes are established here and are demarcated by map positions or nucleotide sequences. Gene has several advantages over its predecessor, LocusLink, including, better integration with other databases in NCBI, broader taxonomic scope, and enhanced options for query and retrieval provided by the Entrez system. [12]


Protein database maintains the text record for individual protein sequences, derived from many different resources such as NCBI Reference Sequence (RefSeq) project, GenBank, PDB, and UniProtKB/SWISS-Prot. Protein records are present in different formats including FASTA and XML and are linked to other NCBI resources. Protein provides the relevant data to the users such as genes, DNA/RNA sequences, biological pathways, expression and variation data, and literature. It also provides the pre-determined sets of similar and identical proteins for each sequence as computed by the BLAST. The Structure database of NCBI contains 3D coordinate sets for experimentally-determined structures in PDB that are imported by NCBI. The Conserved Domain database (CDD) of protein contains sequence profiles that characterize highly conserved domains within protein sequences. It also has records from external resources like SMART and Pfam. There is another database in a protein known as Protein Clusters database which contains sets of proteins sequences that are clustered according to the maximum alignments between the individual sequences as calculated by BLAST. [13]

Pubchem database

PubChem database of NCBI is a public resource for molecules and their activities against biological assays. PubChem is searchable and accessible by Entrez information retrieval system. [14]

See also

Related Research Articles

Sequence alignment Process in bioinformatics that identifies equivalent sites within molecular sequences

In bioinformatics, a sequence alignment is a way of arranging the sequences of DNA, RNA, or protein to identify regions of similarity that may be a consequence of functional, structural, or evolutionary relationships between the sequences. Aligned sequences of nucleotide or amino acid residues are typically represented as rows within a matrix. Gaps are inserted between the residues so that identical or similar characters are aligned in successive columns. Sequence alignments are also used for non-biological sequences, such as calculating the distance cost between strings in a natural language or in financial data.

In bioinformatics, BLAST is an algorithm and program for comparing primary biological sequence information, such as the amino-acid sequences of proteins or the nucleotides of DNA and/or RNA sequences. A BLAST search enables a researcher to compare a subject protein or nucleotide sequence with a library or database of sequences, and identify library sequences that resemble the query sequence above a certain threshold.

Entrez cross-database search engine, or web portal

The Entrez Global Query Cross-Database Search System is a federated search engine, or web portal that allows users to search many discrete health sciences databases at the National Center for Biotechnology Information (NCBI) website. The NCBI is a part of the National Library of Medicine (NLM), which is itself a department of the National Institutes of Health (NIH), which in turn is a part of the United States Department of Health and Human Services. The name "Entrez" was chosen to reflect the spirit of welcoming the public to search the content available from the NLM.

The GenBank sequence database is an open access, annotated collection of all publicly available nucleotide sequences and their protein translations. It is produced and maintained by the National Center for Biotechnology Information as part of the International Nucleotide Sequence Database Collaboration (INSDC).

In molecular genetics, an open reading frame (ORF) is the part of a reading frame that has the ability to be translated. An ORF is a continuous stretch of codons that begins with a start codon and ends at a stop codon. An ATG codon within the ORF may indicate where translation starts. The transcription termination site is located after the ORF, beyond the translation stop codon. If transcription were to cease before the stop codon, an incomplete protein would be made during translation. In eukaryotic genes with multiple exons, introns are removed and exons are then joined together after transcription to yield the final mRNA for protein translation. In the context of gene finding, the start-stop definition of an ORF therefore only applies to spliced mRNAs, not genomic DNA, since introns may contain stop codons and/or cause shifts between reading frames. An alternative definition says that an ORF is a sequence that has a length divisible by three and is bounded by stop codons. This more general definition can also be useful in the context of transcriptomics and/or metagenomics, where start and/or stop codon may not be present in the obtained sequences. Such an ORF corresponds to parts of a gene rather than the complete gene.

A sequence profiling tool in bioinformatics is a type of software that presents information related to a genetic sequence, gene name, or keyword input. Such tools generally take a query such as a DNA, RNA, or protein sequence or ‘keyword’ and search one or more databases for information related to that sequence. Summaries and aggregate results are provided in standardized format describing the information that would otherwise have required visits to many smaller sites or direct literature searches to compile. Many sequence profiling tools are software portals or gateways that simplify the process of finding information about a query in the large and growing number of bioinformatics databases. The access to these kinds of tools is either web based or locally downloadable executables.


Sequerome is a web-based sequence profiling tool for integrating the results of a BLAST sequence-alignment report with external research tools and servers that perform advanced sequence manipulations, and allowing the user to record the steps of such an analysis. Sequerome is a web-based Java tool that acts as a front-end to BLAST queries and provides simplified access to web-distributed resources for protein and nucleic acid analysis.

David J. Lipman American biologist

David J. Lipman is an American biologist who since 1989 to 2017 had been the Director of the National Center for Biotechnology Information (NCBI) at the National Institutes of Health. NCBI is the home of GenBank, the U.S. node of the International Sequence Database Consortium, and PubMed, one of the most heavily used sites in the world for the search and retrieval of biomedical information. Lipman is one of the original authors of the BLAST sequence alignment program, and a respected figure in bioinformatics. In 2017, he left NCBI and became Chief Science Officer at Impossible Foods.

The Biomolecular Object Network Databank is a bioinformatics databank containing information on small molecule and, structures and interactions. The databank integrates a number of existing databases to provide a comprehensive overview of the information currently available for a given molecule.

formatdb is a discontinued software tool that was used in molecular bioinformatics to format protein or nucleotide databases for BLAST. It has been replaced by makeblastdb and the NCBI "strongly encourage[s]" users to stop using formatdb.

BLAT is a pairwise sequence alignment algorithm that was developed by Jim Kent at the University of California Santa Cruz (UCSC) in the early 2000s to assist in the assembly and annotation of the human genome. It was designed primarily to decrease the time needed to align millions of mouse genomic reads and expressed sequence tags against the human genome sequence. The alignment tools of the time were not capable of performing these operations in a manner that would allow a regular update of the human genome assembly. Compared to pre-existing tools, BLAT was ~500 times faster with performing mRNA/DNA alignments and ~50 times faster with protein/protein alignments.

Warren Richard Gish is the owner of Advanced Biocomputing LLC. He joined Washington University in St. Louis as a junior faculty member in 1994, and was a Research Associate Professor of Genetics from 2002 to 2007.


UGENE is computer software for bioinformatics. It works on personal computer operating systems such as Windows, macOS, or Linux. It is released as free and open-source software, under a GNU General Public License (GPL) version 2.

TSR3 protein-coding gene in the species Homo sapiens

TSR3, or TSR3 Ribosome Maturation Factor, is a hypothetical human protein found on chromosome 16. Its protein is 312 amino acids long. and its cDNA has 1214 base pairs It was previously designated C16orf42.

METTL26 protein-coding gene in the species Homo sapiens

METTL26, previously designated C16orf13, is a protein-coding gene for Methyltransferase Like 26, also known as JFP2. Though the function of this gene is unknown, various data have revealed that it is expressed at high levels in various cancerous tissues. Underexpression of this gene has also been linked to disease consequences in humans.

LOC105377021 is a protein which in humans is encoded by the LOC105377021 gene. LOC105377021 exhibits expressional pathology related to breast cancer, specifically triple negative breast cancer. LOC105377021 contains a serine rich region in addition to predicted alpha helix motifs.

C2orf73 protein-coding gene in the species Homo sapiens

Uncharacterized protein C2orf73 is a protein that in humans is encoded by the C2orf73 gene. The protein is predicted to be localized to the nucleus.

Transmembrane protein 44 mammalian protein found in Homo sapiens

Transmembrane protein 44 is a protein that in humans is encoded by the TMEM44 gene.

TMEM44 protein-coding gene in the species Homo sapiens

TMEM44 is a protein that in humans is encoded by the TMEM44 gene. DKFZp686O18124 is a synonym of TMEM44.

C19orf44 mammalian protein found in Homo sapiens

Chromosome 19 open reading frame 44 is a protein that in humans is encoded by the C19orf44 gene. C19orf44 is an uncharacterized protein with an unknown function in humans. C19orf44 is non-limiting implying that the protein exists in other species besides human. The protein contains one domain of unknown function (DUF) that is highly conserved throughout its orthologs. This protein is most highly expressed in the testis and ovary, but also has significant expression in the thyroid and parathyroid. Other names for this protein include: LOC84167.


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  5. 1 2 Mizrachi, Ilene (22 August 2007). GenBank: The Nucleotide Sequence Database. National Center for Biotechnology Information (US) via
  6. "Home - Taxonomy - NCBI".
  7. USA (2019-05-06). "Home - Books - NCBI". Retrieved 2019-06-12.
  8. Altschul Stephen; Gish Warren; Miller Webb; Myers Eugene; Lipman David (1990). "Basic local alignment search tool". Journal of Molecular Biology. 215 (3): 403–410. doi:10.1016/s0022-2836(05)80360-2. PMID   2231712.
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  10. NCBI Resource Coordinators (2012). "Database resources of the National Center for Biotechnology Information". Nucleic Acids Research 41 (Database issue): D8–D20.
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  12. Maglott D. Pruitt K. & Tatusova T. (2005). The NCBI Handbook, 2nd edition, Chapter 19, Gene: A Directory of Genes
  13. Sayers E. (2013). The NCBI Handbook, 2nd edition, NCBI Protein Resources
  14. Wang Y. & Bryant S H. (2014). The NCBI Handbook, 2nd edition, NCBI PubChem BioAssay Database