DR6 in Koreans. DR11 frequently acts as a recipient gene to create DR13 alleles.

DR6 is a complex allele family composed of at least 16 different alleles. Although 25% of Koreans express DR6 alleles, this allele family has not been well studied in the population. DNA samples obtained from 252 unrelated individuals were screened by PCR using Taq DNA polymerase and a DRB1 group-specific PCR primer set that amplifies the polymorphic second exon of DR3, DR11, and DR6 DRB1 alleles. To identify the DR6 allelic frequencies in this population, PCR-positive samples were further analyzed by dot-blot hybridization using digoxigenin-labeled SSOPs. In this process, a new DRB1 allele was identified by its unique hybridization pattern and was further characterized by direct sequencing after PCR. The new DRB1 sequence is similar to DRB11101, differing at codon 47 (TAC[Tyr]/TTC[Phe]) and at codon 58 (GCC[Ala]/GAG[Glu]). Based on sequence comparisons as well as its DRB3 and DQ associations, the new allele may have arisen by a gene conversion event from DRB11101. The resultant DR molecule bears DR6 serologic determinants as determined by serologic typing and, based on sequence, is probably a DR13 and not a DR14 allele. These data suggest that the DR11 allele has frequently acted as a recipient gene in the gene conversion events that created the subfamily of DR13 alleles, DRB1*1303, *1304, *1305, and the new allele described here.