DRB103 diversity and DRB3 associations in five major population groups in the United States

One hundred sixty-one DRB1∗03 positive individuals from each of five U.S. population groups (Caucasoids, African Americans, Asians/Pacific Islanders, Hispanics, and Native Americans) were randomly selected from a database of 82,979 individuals. DRB1∗03 alleles were identified by polymerase chain reaction-sequence-specific oligonucleotide probe typing. A total of six DRB1∗03 alleles out of 21 known alleles were detected. DRB1∗03011 was the predominant DRB1∗03 allele in all populations. Caucasoids were found to be the least diversified; only DRB1∗03011 was observed. African Americans carried DRB1∗03021 at a high frequency. This allele was observed in three other populations. DRB1∗0304 was found in Asians/Pacific Islanders and DRB1∗0305, DRB1∗0307 and a new allele, DRB1∗0316, was found in Hispanics. A subset of individuals was also typed for DRB3 alleles. DRB3∗0101, DRB3∗0202, and DRB3∗0301 were detected and seven DRB1-DRB3 haplotypes were defined. Testing of other individuals not included in the DRB1∗03 frequency study identified a variation of a common extended haplotype, A1, B8, DR3, which carries DRB1∗0304 and two previously unreported DRB1∗03 alleles, DRB1∗0311 and ∗0320, are also described.