title: Definition of a new HLA-B7 subtype (B*0704) by isoelectric focusing, family studies and DNA sequence analysis.
abstract: During screening of potential bone marrow donors, a previously undescribed banding position for the serologically defined HLA-B7 antigen was identified in three unrelated families using one dimensional isoelectric focusing and class I specific Western blot analysis. The isoelectric point of the new variant is more acidic than the two HLA-B7 variants that had been defined before. In each family the new B7 variant was found linked to HLA-A2 and -Cw7. Cloning and sequencing of full-length clones of complementary DNA showed that the new allele (B*0704) differs from B*0702, the common allele encoding HLA-B7, by three nucleotide substitutions within the codon for residue 156 of the mature heavy chain. As a result of these differences amino acid 156 is changed from arginine to aspartic acid, a difference consistent with the isoelectric points. The group of three nucleotide substitutions that distinguish B*0704 from B*0702 is present in other HLA-B alleles.
authors.affiliation: Institute of Immunology, University Hospital, Essen, Germany.
authors.forename: B S
authors.initials: BS
authors.lastname: Kubens
authors.forename: K L
authors.initials: KL
authors.lastname: Arnett
authors.forename: E J
authors.initials: EJ
authors.lastname: Adams
authors.forename: P
authors.initials: P
authors.lastname: Parham
authors.forename: H
authors.initials: H
authors.lastname: Grosse-Wilde
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D002461:Cell Line, Transformed; D002648:Child; D003001:Cloning, Molecular; D004247:DNA; D005260:Female; D014644:Genetic Variation; D015793:HLA-B7 Antigen / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D007525:Isoelectric Focusing; D008297:Male; D008969:Molecular Sequence Data; D010375:Pedigree
chemical_list: D015793:HLA-B7 Antigen; D004247:DNA