We describe the isolation and characterization of two novel HLA-DRB1*11 alleles, officially named DRB1*1161 and 110404. These two new variants were both identified in two Caucasoid individuals. The exon 2 sequence of DRB1*1161 is identical to that of DRB1*110101 except at codon 41, where a nucleotide substitution (GAC>AAC) is responsible for an amino-acidic change from Asp to Asn. The exon 2 sequence of the second novel allele described here, DRB1*110404, differs from that of DRB1*110401 only at codon 34 where the nucleotidic change CAA>CAG gives rise to a silent mutation.