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Correspondence between the different gene nomenclatures.

The major histocompatibility (MH) superfamiliy (MhSF) genes belong to three groups MH1, MH2 and RPI-MH1Like, that also define the three classes MH1, MH2 and RPI-MH1Like.

Major histocompatibility (MH) superfamily (MhSF) groups (1) IMGT chain description (2) IMGT category (3) Previous names (3) IMGT subgroup (1) Other designations from the literature
MH1 I-ALPHA, B2M classical MH1 MHC-Ia Homsap MH1-A HLA-A
Homsap MH1-B HLA-B
Homsap MH1-C HLA-C
nonclassical MH1 MHC-Ib Homsap MH1-E HLA-E
Homsap MH1-F HLA-F
Homsap MH1-G HLA-G
RPI-MH1Like I-ALPHA-LIKE, B2M [2] Homsap CD1
Homsap FCGRT
Homsap HFE
Homsap MR
I-ALPHA-LIKE [2] Homsap AZGP
Homsap MIC
Homsap PROCR
Homsap RAET
MH2 II-ALPHA, II-BETA classical MH2 MHC-IIa Homsap MH2-PA HLA-DPA
Homsap MH2-PB HLA-DPB
Homsap MH2-QA HLA-DQA
Homsap MH2-QB HLA-DQB
Homsap MH2-RA HLA-DRA
Homsap MH2-RB HLA-DRB
nonclassical MH2 MHC-IIb Homsap MH2-OA HLA-DOA
Homsap MH2-OB HLA-DOB
Homsap MH2-MA HLA-DMA
Homsap MH2-MB HLA-DMB
IMGT notes:
(1) The IMGT classification is based on the concepts of IMGT group and IMGT subgroup (CLASSIFICATION axiom of IMGT-ONTOLOGY).
(2) The IMGT description uses the IMGT labels (DESCRIPTION axiom of IMGT-ONTOLOGY). Depending on the RPI-MH1Like, the I-ALPHA-LIKE is bound or unbound to B2M [2].
(3) Classical MH1 and classical MH2 refer to the highly polymorphic MH proteins that present processed peptides to the T cell receptors (previously designated as MHC-Ia and MHC-IIa, respectively).
Nonclassical MH1 and nonclassical MH2 refer to MH proteins with more specific functions and/or which do not present peptides to the T cell receptors (previously designated as MHC-Ib and MHC-IIb, respectively) [1].
Reference:
[1] Lefranc, M.-P. et al., Dev. Comp. Immunol., 29, 917-938 (2005). PMID: 15936075 with permission from Elsevier
[2] Duprat, E. et al. Bioinformatics, 22, 453-459 (2006). Epub 2005 Dec 13. LIGM :309 PMID: 16352655.