The purpose of the BioSamples database is to provide unified storage and access to information about biological samples. These samples may have investigation information stored in other databases (e.g. sequencing, structure, expression). Physical samples may also be available for further study from suppliers. The definition of a sample is flexible. Most samples are straightforward, such as tissue from an individual organism. However, a sample can also be an environmental sample (e.g. for meta-genomic analysis), a hybrid between two species, infected tissue, etc. Within the BioSamples Database, collections of samples are managed as "submission". Each submission is one SampleTab format file emailed to biosamples@ebi.ac.uk. Some highly-curated and highly-referenced submissions may become "reference samples", for example the ENCODE cell lines. These are samples that are of particular interest and have datasets from multiple technologies associated with them. ... [Information of the supplier]