The IMGT/HLA sequence database.

The IMGT/HLA database (wwwebi.ac.uk/imgt/hla/) specialises in sequences of the polymorphic genes of the HLA system, the humanmajor histocompatibility complex (MHC). This complex is located within the 6p213 region on the short arm of human chromosome 6 and contains more than 220 genes of diverse function. Many of the genes encode proteins of the immune system and these include the 21 highly polymorphic HLA genes, which influence the outcome of clinical transplantation and confer susceptibility to a wide range of non-infectious diseases. The database contains sequences for all HLA alleles officially recognised by the WHO Nomenclature Committee for Factors of the HLA System and provides users with online tools and facilities for their retrieval and analysis. These include allele reports, alignment tools, and detailed descriptions of the source cells. The online submission tool allows both new and confirmatory sequences to be submitted directly to the WHO Nomenclature Committee. The latest version (release 1.10.0 April 2001) contains 1329 HLA alleles, 61 HLA related sequences, derived from around 3350 component sequences from the EMBL/ GenBank/DDBJ databases. The IMGT/HLA database provides a model that will be extended to provide specialist databases for polymorphic MHC genes of other species.