The Entrez Nucleotides database is a collection of sequences from several sources, including GenBank, RefSeq, and PDB. The number of bases grows at an exponential rate. As of April 2004, there are over 38,989,342,565 bases. Entrez is the integrated, text-based search and retrieval system used at NCBI for the major databases, including PubMed, Nucleotide and Protein Sequences, Protein Structures, Complete Genomes, Taxonomy, and others.
This permalink is a direct, persistent URL to the database that will always work and won't break.