Gene: HLA-A

Alternate names for this Gene: HLAA

Gene Summary: HLA-A belongs to the HLA class I heavy chain paralogues. This class I molecule is a heterodimer consisting of a heavy chain and a light chain (beta-2 microglobulin). The heavy chain is anchored in the membrane. Class I molecules play a central role in the immune system by presenting peptides derived from the endoplasmic reticulum lumen so that they can be recognized by cytotoxic T cells. They are expressed in nearly all cells. The heavy chain is approximately 45 kDa and its gene contains 8 exons. Exon 1 encodes the leader peptide, exons 2 and 3 encode the alpha1 and alpha2 domains, which both bind the peptide, exon 4 encodes the alpha3 domain, exon 5 encodes the transmembrane region, and exons 6 and 7 encode the cytoplasmic tail. Polymorphisms within exon 2 and exon 3 are responsible for the peptide binding specificity of each class one molecule. Typing for these polymorphisms is routinely done for bone marrow and kidney transplantation. Hundreds of HLA-A alleles have been described. The HLA system plays an important role in the occurrence and outcome of infectious diseases, including those caused by the human immunodeficiency virus (HIV), and the severe acute respiratory syndrome coronavirus (SARS-CoV). The structural spike and the nucleocapsid proteins of the novel coronavirus SARS-CoV-2, which causes coronavirus disease 2019 (COVID-19), are reported to contain multiple Class I epitopes with predicted HLA restrictions.

Gene is located in Chromosome: 6

Location in Chromosome : 6p22.1

Description of this Gene: major histocompatibility complex, class I, A

Type of Gene: protein-coding

Gene: HCG9

Alternate names for this Gene: HCGIX|HCGIX4

Gene Summary: This gene lies within the MHC class I region on chromosome 6p21.3. This gene is believed to be non-coding, but its function has not been determined.

Gene is located in Chromosome: 6

Location in Chromosome : 6p22.1

Description of this Gene: HLA complex group 9

Type of Gene: ncRNA

rs3132685 in HLA-A;HCG9 gene and Adenocarcinoma of lung (disorder) PMID 19836008 2009 A genome-wide association study of lung cancer identifies a region of chromosome 5p15 associated with risk for adenocarcinoma.

rs2394250 in HLA-A;HCG9 gene and Ankylosing spondylitis PMID 23749187 2013 Identification of multiple risk variants for ankylosing spondylitis through high-density genotyping of immune-related loci.

rs3132685 in HLA-A;HCG9 gene and Diabetes Mellitus, Insulin-Dependent PMID 17632545 2007 A genome-wide association study identifies KIAA0350 as a type 1 diabetes gene.

rs3132685 in HLA-A;HCG9 gene and Lupus Erythematosus, Systemic PMID 24871463 2014 GWAS identifies novel SLE susceptibility genes and explains the association of the HLA region.

rs3132685 in HLA-A;HCG9 gene and Major Depressive Disorder PMID 29662059 2018 Genome-wide association study of depression phenotypes in UK Biobank identifies variants in excitatory synaptic pathways.

rs3132685 in HLA-A;HCG9 gene and Malignant neoplasm of lung PMID 22899653 2012 Influence of common genetic variation on lung cancer risk: meta-analysis of 14 900 cases and 29 485 controls.

PMID 19654303 2009 Deciphering the impact of common genetic variation on lung cancer risk: a genome-wide association study.

rs3132685 in HLA-A;HCG9 gene and Myasthenia Gravis PMID 23055271 2012 Risk for myasthenia gravis maps to a (151) Pro→Ala change in TNIP1 and to human leukocyte antigen-B*08.

rs6904029 in HLA-A;HCG9 gene and Rheumatoid Arthritis PMID 17804836 2007 TRAF1-C5 as a risk locus for rheumatoid arthritis--a genomewide study.

PMID 19503088 2009 REL, encoding a member of the NF-kappaB family of transcription factors, is a newly defined risk locus for rheumatoid arthritis.

rs6904029 in HLA-A;HCG9 gene and Vitiligo PMID 20410501 2010 Variant of TYR and autoimmunity susceptibility loci in generalized vitiligo.