title: Relative HLA-DRB1*13 allele frequencies and DRB3 associations of unrelated individuals from five US populations.
abstract: The frequencies of 30 HLA-DRB1*13 alleles and 15 DRB3 alleles were determined for the 5 major U.S. ethnic populations: Caucasians, African Americans, Asian/Pacific Islanders, Hispanics, and Native Americans. A random sampling (163) of DRB1*13-positive individuals from each self-described ethnic group was selected out of a pool of 82,979 unrelated individuals, providing at least an 80% probability of detecting a rare allele that occurred at 1%. These 815 samples were subjected to allele-level SSOP typing and/or DNA sequencing which identified 11 different DRB1*13 alleles. DRB1*1301 and DRB1*1302 were the most common alleles seen in the five major ethnic groups while DRB1*1304 was not detected among Caucasians and DRB1*1305 was not detected among African Americans. DRB1*13 allele diversity was surprisingly more limited among African Americans compared to both Caucasians and Asian/Pacific Islanders. To determine the extent of DRB1*13-DRB3 associations, 504 of these samples expressing only one DRB3-associated DRB1 allele were subjected to PCR-SSOP typing and 14 DRB1*13-DRB3 haplotypes were detected. The distribution revealed that African Americans were significantly different from Caucasians, Asian/Pacific Islanders, and Hispanics. Allele frequency studies such as this further support previous findings that the distribution of HLA types can differ significantly among different ethnic populations.
authors.affiliation: Department of Microbiology, Georgetown University Medical Center, Washington, District of Columbia 20007, USA.
authors.forename: D M
authors.initials: DM
authors.lastname: Sintasath
authors.forename: T
authors.initials: T
authors.lastname: Tang
authors.forename: R
authors.initials: R
authors.lastname: Slack
authors.forename: E E
authors.initials: EE
authors.lastname: Tilley
authors.forename: J
authors.initials: J
authors.lastname: Ng
authors.forename: R J
authors.initials: RJ
authors.lastname: Hartzman
authors.forename: C K
authors.initials: CK
authors.lastname: Hurley
mesh_terms: D000483:Alleles; D016208:Databases, Factual; D005787:Gene Frequency; D006684:HLA-DR Antigens / Q000235:genetics*; D059811:HLA-DRB1 Chains; D059826:HLA-DRB3 Chains; D006801:Humans; D015345:Oligonucleotide Probes; D010641:Phenotype; D044469:Racial Groups / Q000235:genetics*; D012680:Sensitivity and Specificity; D014481:United States
chemical_list: D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; D059826:HLA-DRB3 Chains; D015345:Oligonucleotide Probes