title: The relationship between HLA-B45 and B* 5002 in the five major U.S. population groups.
abstract: The antigen encoded by B*5002 differs in sequence from that encoded by B*5001 only at amino acid residue 167 (consensus tryptophan vs. serine) which results in B45 serologic reactivity. To search for B*5002, the frequencies of alleles encoding the serologically defined B45 antigen were determined by sequence-based typing in 5 major U.S. populations: Caucasians, African Americans, Asians/Pacific Islanders, Hispanics, and Native Americans. The percent of serologically defined B45-positive individuals in the 5 populations ranged from 0.7-9.0%. Thirty-two B45-positive individuals were randomly chosen, when available, for sequence-based typing from each ethnic group from a database of 82,979 consecutively typed unrelated individuals. The B*5002 allele was most prevalent in Hispanic (22%) and Caucasian (9%) individuals, while conspicuously absent in African Americans. In addition, a new allele associated with the B45 antigenic specificity, B*4502, has been identified from an African American individual of Middle Eastern descent. In light of the continuing need to reconcile differences between relationships determined by the sequence homologies among alleles and relationships based on the serologic determinants carried by allelic products when determining the level of HLA match for hematopoietic stem cell transplantation, it is suggested that B*5002 be recognized individually from other B*50 alleles when reporting HLA-B typings for clinical purposes.
authors.affiliation: Department of Microbiology, Georgetown University Medical Center, Washington, DC 20007, USA.
authors.forename: C
authors.initials: C
authors.lastname: Kosman
authors.forename: N
authors.initials: N
authors.lastname: Steiner
authors.forename: H
authors.initials: H
authors.lastname: Pulyaeva
authors.forename: W
authors.initials: W
authors.lastname: Mitton
authors.forename: R
authors.initials: R
authors.lastname: Slack
authors.forename: R J
authors.initials: RJ
authors.lastname: Hartzman
authors.forename: J
authors.initials: J
authors.lastname: Ng
authors.forename: C K
authors.initials: CK
authors.lastname: Hurley
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D044466:Asian People / Q000235:genetics; D001483:Base Sequence; D044383:Black People / Q000235:genetics; D005787:Gene Frequency; D015235:HLA-B Antigens / Q000235:genetics*; D006801:Humans; D007198:Indians, North American / Q000235:genetics; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D044469:Racial Groups / Q000235:genetics*; D017422:Sequence Analysis, DNA; D014481:United States; D044465:White People / Q000235:genetics; D001741:Black or African American
chemical_list: D015235:HLA-B Antigens; C077377:HLA-B45 antigen; D015345:Oligonucleotide Probes