A nucleotide insertion in exon 4 is responsible for the absence of expression of an HLA-A*01 allele.
HLA class I typing performed in parallel by molecular biology and serology has revealed cases where an HLA class I allele was identified whereas the corresponding antigen was not detected on the cell surface. In the present report, we describe four members of a family in whom an HLA-A1 allele identified at the molecular level was typed as A "blank" by lymphocytotoxicity. This serologically blank antigen was undetectable by isoelectric focusing (IEF). Sequencing of the HLA-A*01 allele from the promoter region to the eighth exonic region revealed insertion of a "C" nucleotide at the beginning of the fourth exon as compared to the common HLA-A*0101 allele. This mutation causes a frame shift, giving rise to an early stop codon in the fourth exon.
Laforet
M
M
Laboratoire d'Histocompatibilité Etablissement de Transfusion Sanguine, Strasbourg, France. hla@etss.u-strasbg.fr
Froelich
N
N
Parissiadis
A
A
Pfeiffer
B
B
Schell
A
A
Faller
B
B
Woehl-Jaegle
M L
ML
Cazenave
J P
JP
Tongio
M M
MM
D000483:Alleles; D003062:Codon / Q000235:genetics; D004252:DNA Mutational Analysis; D005091:Exons / Q000235:genetics*; D005260:Female; D016368:Frameshift Mutation; D015870:Gene Expression; D005805:Genes, MHC Class I; D015788:HLA-A1 Antigen / Q000096:biosynthesis / Q000235:genetics*; D006650:Histocompatibility Testing; D006801:Humans; D016030:Kidney Transplantation / Q000276:immunology; D008297:Male; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D016133:Polymerase Chain Reaction; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D012698:Serologic Tests; D013728:Terminator Regions, Genetic / Q000235:genetics
D003062:Codon; D015788:HLA-A1 Antigen