IGH@

Immunoglobulin heavy locus
Identifiers
Symbols	IGH@ ; IGH; IGH.1@; IGHDY1
Gene ontology
Orthologs
Template:GNF Ortholog box
Species	Human	Mouse
Entrez	n/a	n/a
Ensembl	n/a	n/a
UniProt	n/a	n/a
RefSeq (mRNA)	n/a	n/a
RefSeq (protein)	n/a	n/a
Location (UCSC)	n/a	n/a
PubMed search	n/a	n/a

Immunoglobulin heavy locus, also known as IGH@, is a region on human chromosome 14 that contains gene for the heavy chains of human antibodies (or immunoglobulins).

Immunoglobulins recognize foreign antigens and initiate immune responses such as phagocytosis and the complement system. Each immunoglobulin molecule consists of two identical heavy chains and two identical light chains. This region represents the germline organization of the heavy chain locus. The locus includes V (variable), D (diversity), J (joining), and C (constant) segments. During B cell development, a recombination event at the DNA level joins a single D segment with a J segment; this partially rearranged D-J gene is then joined to a V segment. The rearranged V-D-J is then transcribed with the IGHM constant region; this transcript encodes a mu heavy chain. Later in development B cells generate V-D-J-Cmu-Cdelta pre-messenger RNA, which is alternatively spliced to encode either a mu or a delta heavy chain. Mature B cells in the lymph nodes undergo switch recombination, so that the V-D-J gene is brought in proximity to one of the IGHG, IGHA, or IGHE genes and each cell expresses either the gamma, alpha, or epsilon heavy chain. Recombination of many different V segments with several J segments provides a wide range of antigen recognition. Additional diversity is attained by junctional diversity, resulting from the random additional of nucleotides by terminal deoxynucleotidyltransferase, and by somatic hypermutation, which occurs during B cell maturation in the spleen and lymph nodes. Several V, D, J, and C segments are known to be incapable of encoding a protein and are considered pseudogenes.

Further reading

• Tomlinson IM, Cook GP, Walter G; et al. (1995). "A complete map of the human immunoglobulin VH locus". Ann. N. Y. Acad. Sci. 764: 43–6. PMID 7486559.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)
• Word CJ, White MB, Kuziel WA; et al. (1991). "The human immunoglobulin C mu-C delta locus: complete nucleotide sequence and structural analysis". Int. Immunol. 1 (3): 296–309. PMID 2518659.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)
• Buluwela L, Rabbitts TH (1989). "A VH gene is located within 95 Kb of the human immunoglobulin heavy chain constant region genes". Eur. J. Immunol. 18 (11): 1843–5. PMID 3144456.
• Ichihara Y, Matsuoka H, Kurosawa Y (1989). "Organization of human immunoglobulin heavy chain diversity gene loci". EMBO J. 7 (13): 4141–50. PMID 3243276.CS1 maint: Multiple names: authors list (link)
• Ravetch JV, Siebenlist U, Korsmeyer S; et al. (1993). "Structure of the human immunoglobulin mu locus: characterization of embryonic and rearranged J and D genes". Cell. 27 (3 Pt 2): 583–91. PMID 6101209.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)
• Flanagan JG, Rabbitts TH (1983). "Arrangement of human immunoglobulin heavy chain constant region genes implies evolutionary duplication of a segment containing gamma, epsilon and alpha genes". Nature. 300 (5894): 709–13. PMID 6817141.
• Mills FC, Harindranath N, Mitchell M, Max EE (1997). "Enhancer complexes located downstream of both human immunoglobulin Calpha genes". J. Exp. Med. 186 (6): 845–58. PMID 9294139.CS1 maint: Multiple names: authors list (link)
• Matsuda F, Ishii K, Bourvagnet P; et al. (1999). "The complete nucleotide sequence of the human immunoglobulin heavy chain variable region locus". J. Exp. Med. 188 (11): 2151–62. PMID 9841928.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)
• Dudley DD, Manis JP, Zarrin AA; et al. (2002). "Internal IgH class switch region deletions are position-independent and enhanced by AID expression". Proc. Natl. Acad. Sci. U.S.A. 99 (15): 9984–9. doi:10.1073/pnas.152333499. PMID 12114543.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)
• Zhou J, Ashouian N, Delepine M; et al. (2002). "The origin of a developmentally regulated Igh replicon is located near the border of regulatory domains for Igh replication and expression". Proc. Natl. Acad. Sci. U.S.A. 99 (21): 13693–8. doi:10.1073/pnas.212392399. PMID 12370427.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)
• Strausberg RL, Feingold EA, Grouse LH; et al. (2003). "Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences". Proc. Natl. Acad. Sci. U.S.A. 99 (26): 16899–903. doi:10.1073/pnas.242603899. PMID 12477932.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)
• Ota T, Suzuki Y, Nishikawa T; et al. (2004). "Complete sequencing and characterization of 21,243 full-length human cDNAs". Nat. Genet. 36 (1): 40–5. doi:10.1038/ng1285. PMID 14702039.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)
• Li A, Rue M, Zhou J; et al. (2004). "Utilization of Ig heavy chain variable, diversity, and joining gene segments in children with B-lineage acute lymphoblastic leukemia: implications for the mechanisms of VDJ recombination and for pathogenesis". Blood. 103 (12): 4602–9. doi:10.1182/blood-2003-11-3857. PMID 15010366.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)
• Hallermann C, Kaune KM, Gesk S; et al. (2004). "Molecular cytogenetic analysis of chromosomal breakpoints in the IGH, MYC, BCL6, and MALT1 gene loci in primary cutaneous B-cell lymphomas". J. Invest. Dermatol. 123 (1): 213–9. doi:10.1111/j.0022-202X.2004.22720.x. PMID 15191563.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)
• Sepulveda MA, Garrett FE, Price-Whelan A, Birshtein BK (2005). "Comparative analysis of human and mouse 3' Igh regulatory regions identifies distinctive structural features". Mol. Immunol. 42 (5): 605–15. doi:10.1016/j.molimm.2004.09.006. PMID 15607820.CS1 maint: Multiple names: authors list (link)
• Streubel B, Vinatzer U, Lamprecht A; et al. (2005). "T(3;14)(p14.1;q32) involving IGH and FOXP1 is a novel recurrent chromosomal aberration in MALT lymphoma". Leukemia. 19 (4): 652–8. doi:10.1038/sj.leu.2403644. PMID 15703784.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)
• Knezevich S, Ludkovski O, Salski C; et al. (2005). "Concurrent translocation of BCL2 and MYC with a single immunoglobulin locus in high-grade B-cell lymphomas". Leukemia. 19 (4): 659–63. doi:10.1038/sj.leu.2403661. PMID 15716988.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)
• Rack K, Delannoy A, Ravoet C; et al. (2005). "Translocation of BCL2 and BCL6 to the same immunoglobulin heavy chain locus in a case of follicular lymphoma". Leuk. Lymphoma. 46 (10): 1513–6. doi:10.1080/10428190500125648. PMID 16194898.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)