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Finding Sequence Using NCBI Nucleotide

This guide introduces the NCBI Nucleotide database and provides a workflow for using it to find sequences.

The Scope of this Guide

This guide is based on a Welch Medical Library class on finding gene-based information using the web interface of the National Center for Biotechnology Information (NCBI).

It situates the Nucleotide database in the broader context of NCBI's mission and NCBI's suite of related databases. It then summarizes Nucleotide's content, scope, and searching features. Finally, the guide walks users step-by-step through a use case on finding sequences for a family of genes.

Far from an exhaustive look at Nucleotide, this guide nevertheless provides an excellent starting point for understanding its scope and effectively searching its content.

Learning Objectives

After reading through this guide, users will be able to do the following in NCBI Nucleotide:

  • Use a concept-based approach to searching
  • Use trusted sources for finding gene names when constructing searches
  • Use advanced searching tools, such as fields tags, truncation, quotation marks, Boolean operators, and index lists
  • Navigate and export search results

Companion Library Class

A hands-on companion class from the Welch Medical Library called "NCBI Nucleotide, Gene, and dbSNP Databases" exists for this guide. It is currently offered a few times a year. Check the Welch Classes calendar for the next offering of the class.

Class Description

The Nucleotide, Gene, and dbSNP databases from the National Center for Biotechnology Information (NCBI) provide a wealth of gene-based information. Nucleotide organizes and makes searchable sequence data from multiple sources, including GenBank and RefSeq. Gene provides detailed information, including gene ontology and genomic context, for known and predicted genes from all major taxonomic groups. And dbSNP archives human single nucleotide variations, microsatellites, and small-scale insertions and deletions.

This class outlines the content, scope, and searching features of NCBI’s Nucleotide, Gene, and dbSNP databases. Real-world searching scenarios are presented for finding sequence, gene ontology, and variants. Participants are guided live through hands-on searching workflows using the web interfaces of each database. Participants learn how to:

  • Use a concept-based approach to searching
  • Use trusted sources for finding gene names and gene ontology when constructing searches
  • Use advanced searching tools, such as fields, truncation, quotation marks, Boolean operators, and index lists
  • Navigate and export search results
An Additional Related Guide

A guide called "Finding Gene Attributes Using NCBI Gene" was developed based on this class. This guide is structured just like the guide you are using now and presents similar information.

It situates the Gene database in the broader context of NCBI's mission and NCBI's suite of related databases. It then summarizes Gene's content, scope, and searching features. Finally, the guide walks users step-by-step through a use case on finding genes by gene ontology.