title: Full-length cDNA nucleotide sequence of a serologically undetectable HLA-DQA1 allele: HLA-DQA1*"LA".
abstract: This study describes the characterization of a serological HLA-DQ"blank" specificity that segregates with the HLA-A2, -B7, -DR14, -DR52 haplotype. Although conventional serological typing techniques could not detect an HLA-DQ product on the haplotype positive for the HLA-DQ"blank" specificity, sequence-specific oligonucleotide (SSO) dot-blot analysis demonstrated the presence of the HLA-DQA1*01 and HLA-DQB1*05 alleles. Full-length cDNA nucleotide sequence analysis revealed that the HLA-DQB1 allele that segregated with the HLA-DQ"blank" specificity was identical to HLA-DQB1*05031. As for the HLA DQA1 allele, one nucleotide substitution distinguished the HLA-DQA1 "blank" allele from HLA-DQA1*0104. In exon 2 at nucleotide position 304 a C was substituted for a T (Arg-->Cys). Pending official recognition by the WHO Nomenclature Committee, this HLA-DQA1 "blank" allele is termed HLA-DQA1*"LA". Furthermore, it is postulated that the introduction of cysteine at amino acid position 102 abrogates the classical HLA-DQ1 specificity.
authors.affiliation: Department of HLA Diagnostics, Central Laboratory of the Dutch Red Cross Blood Transfusion Service, Amsterdam, The Netherlands.
authors.forename: N M
authors.initials: NM
authors.lastname: Lardy
authors.forename: N
authors.initials: N
authors.lastname: Otting
authors.forename: A R
authors.initials: AR
authors.lastname: van der Horst
authors.forename: R E
authors.initials: RE
authors.lastname: Bontrop
authors.forename: L P
authors.initials: LP
authors.lastname: de Waal
mesh_terms: D000483:Alleles; D001483:Base Sequence; D018076:DNA, Complementary / Q000235:genetics*; D005260:Female; D005802:Genes, MHC Class II; D005838:Genotype; D006683:HLA-DQ Antigens / Q000032:analysis / Q000235:genetics*; D059848:HLA-DQ alpha-Chains; D006650:Histocompatibility Testing; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D010375:Pedigree; D010641:Phenotype; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics; D012698:Serologic Tests
chemical_list: D018076:DNA, Complementary; D006683:HLA-DQ Antigens; D059848:HLA-DQ alpha-Chains; C069050:HLA-DQA1 antigen; D012333:RNA, Messenger