IGK (Immunoglobulin Kappa)

2000-07-01   Marie-Paule Lefranc 

IMGT, LIGM, IGH, UPR CNRS 1142, 141 rue de la Cardonille, 34396 Montpellier Cedex 5, France

Identity

HGNC
IGK
LOCATION
2p11.2
IMAGE
Atlas Image
LEGEND
for complete Figure, see: chromosome 2, IMGT (The International ImMunoGeneTics information system ®) © Copyright 1995-2017 IMGT, IMGT is a CNRS trademark
LOCUSID
50802
ALIAS
IGK@

DNA/RNA

Atlas Image
IGK
V-GENE: Green box: Functional; Yellow box: Open reading frame; Red: Pseudogene.
J-GENE: Grey: Functional .
C-GENE: Blue: Functional.
for complete Figure, see: locus IGK, IMGT (The International ImMunoGeneTics information system ®) © Copyright 1995-2017 IMGT, IMGT is a CNRS trademark

Description

  • The human IGK locus at 2p12 spans 1820 kb. It consists of 76 IGKV genes belonging to 7 subgroups, 5 IGKJ segments, and a unique IGKC gene
  • The 76 IGKV genes are organized in two clusters separated by 800 kb. The IGKV distal cluster (the most 5 from IGKC and in the most centromeric position) spans 400 kb and comprises 36 genes. The IGKV proximal cluster (in 3 of the locus, closer to IGKC, and in the most telomeric position) spans 600 kb and comprises 40 genes.
  • The potential genomic IGK repertoire comprises 31 to 35 functional IGKV genes belonging to 5 subgroups, the 5 IGKJ segments, and the unique IGKC gene.
  • One rare IGKV haplotype has been described which contains only the proximal cluster. This haplotype comprises the 40 proximal IGKV genes belonging to 7 subgroups, of which 17 to 19 are functional and belong to 5 subgroups.
  • Twenty-eight IGKV orphons have been identified and sequenced: 3 on the short arm of chromosome 2 but outside of the main IGK locus, 13 on the long arm of chromosome 2, 6 on chromosome 22, one on chromosome 1, one on chromosome 15, and 4 outside of chromosome 2
  • If both the proximal and distal IGKV clusters are present, the total number of human IGK genes per haploid genome is 82 (110 genes, if the orphons are included) of which 37-41 are functional. If only the proximal IGKV cluster is present, the total number of genes per haploid genome is 46 (74 genes, if the orphons are included) of which 23-25 genes are functional.
  • List of the human IGK genes

    • Mutations

    Note

    Mutations which correspond to allelic polymorphisms of the functional germline IGKV, IGKJ and IGKC genes are described in the IMGT database: (IMGT Repertoire> Alignments of alleles)

    Implicated in

    Entity name
    Translocations which frequently result from errors of the recombinase enzyme complexe (RAG1, RAG2, etc.), which is responsable of the Immunoglobulin and T cell receptor V-J and V-D-J rearrangements. IGKV or IGKJ recombination signals or isolated heptamer are observed at the breakpoints
    Atlas Image
    c-Immunoglobulin genes IgK at 2p12, in normal cells: PAC 1117G4 - Courtesy Mariano Rocchi, Resources for Molecular Cytogenetics.
    Entity name
    t(2;3;)(p12;q27); involve IGK - BCL6 in 3q27
    Disease
    B-cell non-Hodgkin lymphomas (NHL), mainly diffuse large cell lymphoma; adult aggressive lymphoma
    Prognosis
    controversial
    Entity name
    t(2;8)(p12;q24); involve IGK - C-MYC in 8q24
    Disease
    B-cell acute lymphoblastic leukemia (ALL3) and non-Hodgkin lymphomas (NHL), especially in the Burkitt lymphoma
    Prognosis
    the prognosis has evolved with new treatments

    Breakpoints

    Atlas Image

    Bibliography

    Pubmed IDLast YearTitleAuthors

    Other Information

    Locus ID:

    NCBI: 50802
    HGNC: 5715

    Variants:

    dbSNP: 50802
    ClinVar: 50802
    COSMIC: IGK

    References

    Pubmed IDYearTitleCitations
    126150022003A significant fraction of conserved noncoding DNA in human and mouse consists of predicted matrix attachment regions.33
    175460322007Allelic 'choice' governs somatic hypermutation in vivo at the immunoglobulin kappa-chain locus.22
    153561362004Unraveling the consecutive recombination events in the human IGK locus.13
    205051432010Ig-free light chains play a crucial role in murine mast cell-dependent colitis and are associated with human inflammatory bowel diseases.13
    223967842012EBV-encoded LMP1 upregulates Igκ 3'enhancer activity and Igκ expression in nasopharyngeal cancer cells by activating the Ets-1 through ERKs signaling.10
    227059882012IGKV3 proteins as candidate "off-the-shelf" vaccines for kappa-light chain-restricted B-cell non-Hodgkin lymphomas.9
    264298762015IGK with conserved IGΚV/IGΚJ repertoire is expressed in acute myeloid leukemia and promotes leukemic cell migration.8
    233765562013Free light chain monomer-dimer patterns in the diagnosis of multiple sclerosis.6
    245987402014Role of κ→λ light-chain constant-domain switch in the structure and functionality of A17 reactibody.6
    257003442015Immunoglobulin kappa variable region gene selection during early human B cell development in health and systemic lupus erythematosus.6

    Citation

    Marie-Paule Lefranc

    IGK (Immunoglobulin Kappa)

    Atlas Genet Cytogenet Oncol Haematol. 2000-07-01

    Online version: http://atlasgeneticsoncology.org/gene/17/case-report-explorer/haematological-explorer/