Identification of four new DR52-associated DRB1 alleles: DRB1*1424, *1425, *1323 and *1324.

Four previously unreported DR52-associated DRB1 alleles have been characterized through DNA sequencing, contributing to the diversity of the HLA system. DRB11424 is nearly identical to DRB11402 in the second exon, except that it contains the "I---A" motif found at codons 67-71 common to the DRB115 alleles. DRB11425 contains the "A--H" motif, found in DRB11401 at codons 57-60, in a sequence otherwise identical with the second exon of DRB11307. Compared with DRB111012, DRB11323 contains three predicted amino acid changes at codons 58 (ala-->glu), 67 (phe-->ile), and 71 (arg-->glu). The sequence of DRB11324 is identical to exon 2 of DRB11103, except that DRB11324 does not contain the GAG at codon 58 characteristic of the DRB111 alleles. These new alleles may have arisen through gene conversion, and they contribute to the complexity of the DR6 family.