A novel DRB1*13 allele (DRB1*1327) on a DR17, DQ2 haplotype with a DRB1*0301 sequence motif in the 2nd hyperpolymorphic region.

In a sample from a Netherlands Caucasian, we found a new DRB113 allele (DRB11327). The nucleotide sequence of the second exon of the novel allele was identical to DRB11301 except for a single productive base substitution changing codon 26 from TTC to TAC, encoding phenylalanine and tyrosine, respectively. The new allele shares sequence with DRB103011 from codons 5 to 66. The haplotype carrying the new allele was, from known linkage disequilibria, deduced to be DRB11327, DRB30101, DQA105011, DQB10201, i.e. similar to the DR17, DQ2 haplotype, which suggests that the DRB1*1327 allele has arisen by a double recombination event between a DR13 donor haplotype and a DR17, DQ2 recipient haplotype.