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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 1.138 (March 2019) is based on ENA release number 138 (NOV-2018). Release history and plan


ITSoneDB Content

Number of the nucleotide sequences 1,174,761
Total number of species (according to the NCBI taxonomy) 157,531
Number of ITS1 nucleotide sequences with start and end positions inferred by both ENA information and HMM profiles 240,430
Number of ITS1 nucleotide sequences with start and end position inferred only by HMM profiles mapping 346,624
Number of ITS1 nucleotide sequences with start and end position inferred only by ENA information 587,707