Contact us

ITSoneDB: Eukaryal Ribosomal Internal Transcribed Spacer 1 Database


ITSoneDB is a comprehensive collection of eukaryotic ribosomal RNA Internal Transcribed Spacer 1 (ITS1) sequences. It is aimed at supporting metabarcoding surveys of fungal and other microbial eukaryotic environmental communities. The sequences were extracted from the European Nucleotide Archive (ENA) and arranged on the NCBI taxonomy tree. ITS1 start and end boundaries were defined by ENA annotations and/or designed by mapping Hidden Markov Model (HMM) profiles of flanking 18S and 5.8S ribosomal RNA coding genes on each sequence.

Current ITSoneDB release 1.131 (August 2017) is based on ENA release number 131 (2017). Release history and plan


ITSoneDB Content

Number of the nucleotide sequences 985,240
Total number of species (according to the NCBI taxonomy) 134,598
Number of ITS1 nucleotide sequences with start and end positions inferred by both ENA information and HMM profiles 165,612
Number of ITS1 nucleotide sequences with start and end position inferred only by HMM profiles mapping 276,362
Number of ITS1 nucleotide sequences with start and end position inferred only by ENA information 543,266