title: Cloning and complete sequence of an HLA-A2 gene: analysis of two HLA-A alleles at the nucleotide level.
abstract: The gene for the HLA-A2 antigen has been cloned from the human lymphoblastoid cell line 721. Comparison of this sequence with the published sequence for HLA-A3 permits the examination of two alleles at the extremely polymorphic HLA-A locus. A high degree of sequence conservation was seen in both coding and noncoding DNA, 97.2% and 94.5%, respectively. Interestingly, the 3' untranslated region was the most conserved, with 99.5% homology. The polymorphism of the HLA-A antigens results from a high proportion of amino acid substitutions relative to the total nucleotide changes in exons 2 and 3. Unlike the clustered differences seen in this region on comparison of two H-2K alleles of mouse, nucleotide substitutions between the HLA-A2 and A3 alleles are evenly distributed. Substitutions at silent sites and within introns were used to calculate an intra-allelic divergence time of at least 10 to 15 million years for these two HLA-A alleles.
authors.forename: B H
authors.initials: BH
authors.lastname: Koller
authors.forename: H T
authors.initials: HT
authors.lastname: Orr
mesh_terms: D000483:Alleles; D000818:Animals; D000954:Antigens, Surface / Q000032:analysis; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D004262:DNA Restriction Enzymes / Q000032:analysis*; D005802:Genes, MHC Class II; D005815:Genetic Code; D006183:H-2 Antigens / Q000235:genetics; D006680:HLA Antigens / Q000032:analysis / Q000235:genetics*; D015789:HLA-A2 Antigen; D064532:Histocompatibility Antigen H-2D; D006801:Humans; D007739:L Cells / Q000276:immunology; D051379:Mice; D018139:Simplexvirus / Q000235:genetics; D014162:Transfection
chemical_list: D000954:Antigens, Surface; D006183:H-2 Antigens; D006680:HLA Antigens; D015789:HLA-A2 Antigen; D064532:Histocompatibility Antigen H-2D; D004262:DNA Restriction Enzymes