The 'core' concept describes the coding sequences of the V, D, J and C genes, which are potentially found in mature Ig or TcR proteins. The 'core' concept contains four instances (V-REGION, D-REGION, J-REGION and C-REGION). These instances are particularly important since they can be identified in all related germline or rearranged entities as well as in protein sequences and in effective antibodies or T cell receptors.
The 'core' concept is part of the 'DESCRIPTION' concept of IMGT-ONTOLOGY.
 Giudicelli, V. and Lefranc, M.-P., Bioinformatics, 15, 1047-1054 (1999) PMID: 10745995, LIGM:221