IMGT , the international ImMunoGeneTics information system

IMGT , the international ImMunoGeneTics information system (http://www.imgt.org), was created in 1989 by Marie-Paule Lefranc, Laboratoire d’ImmunoGénétique Moléculaire LIGM (Université Montpellier 2 and CNRS) at Montpellier, France, in order to standardize and manage the complexity of immunogenetics data. The building of a unique ontology, IMGT-ONTOLOGY, has made IMGT the global reference in immunogenetics and immunoinformatics. IMGT is a high-quality integrated knowledge resource specialized in the immunoglobulins or antibodies, T cell receptors, major histocompatibility complex, of human and other vertebrate species, proteins of the IgSF and MhcSF, and related proteins of the immune systems of any species. IMGT provides a common access to standardized data from genome, proteome, genetics and 3D structures. IMGT consists of five databases (IMGT/ LIGM-DB, IMGT/GENE-DB, IMGT/3Dstructure-DB, etc.), fifteen interactive online tools for sequence, genome and 3D structure analysis, and more than 10 000 HTML pages of synthesis and knowledge. IMGT is used in medical research (autoimmune diseases, infectious diseases, AIDS, leukemias, lymphomas and myelomas), veterinary research, biotechnology related to antibody engineering (phage displays, combinatorial libraries, chimeric, humanized and human antibodies), diagnostics (clonalities, detection and follow-up of residual diseases) and therapeutical approaches (graft, immunotherapy, vaccinology). IMGT is freely available at http:// www.imgt. org. INTRODUCTION The number of genomics, genetics, 3D and functional data published in the immunogenetics field is growing exponentially and involves fundamental, clinical, veterinary, and pharmaceutical research. The number of potential protein forms of the antigen receptors, immunoglobulins (IG) and T cell receptors (TR) is almost unlimited. The potential repertoire of each individual is estimated to comprise about 10 different IG (or antibodies) and TR, and the limiting factor is only the number of B and T cells that an organism is genetically programmed to produce. This huge diversity is inherent to the particularly complex and unique molecular synthesis and genetics of the antigen receptor chains. This includes biological mechanisms such as DNA molecular rearrangements in multiple loci (three for IG and four for TR in humans) located on different chromosomes (four in humans), nucleotide deletions and insertions at the rearrangement junctions (or N-diversity), and somatic hypermutations in the IG loci (1,2). IMGT , the international ImMunoGeneTics information system (http://www.imgt.org) (3), was created in 1989 by Marie-Paule Lefranc, Laboratoire d’ImmunoGénétique Moléculaire LIGM (Université Montpellier 2 and CNRS) at Montpellier, France, in order to standardize and manage the complexity of immunogenetics data. IMGT has reached that goal through the building of a unique ontology, IMGT-ONTOLOGY (4), the first ontology in immunogenetics and immunoinformatics. IMGTONTOLOGY has allowed the setting up of the official nomenclature of the IG and TR genes and alleles (5,6), the definition of IMGT standardized labels, and the IMGT unique numbering that bridges the gap between sequences and 3D structures for the variable (V) and constant (C) domains of the IG and TR (7–10) and for the groove (G) domains of the major histocompatibility *To whom correspondence should be addressed. Tel: +33 4 99 61 99 65; Fax: +33 4 99 61 99 01; Email: marie-paule.lefranc@igh.cnrs. fr