Two novel human leucocyte antigen (HLA) class I alleles were characterized by means of sequencing-based typing techniques. HLA-A*310103 was identified in a cord blood unit from a Caucasoid individual. The sequence of this allele is identical to that of HLA-A*310102 except for a silent mutation in exon 3 at position 480 (G → A). HLA-B*9531 was found in a Caucasoid female patient registered on the heart transplantation waiting list in the North Italy Transplant programme. This new variant differs from HLA-B*1503 at position 572 (G → C) in exon 3. This nucleotide change leads to an amino acidic substitution at codon 167 from tryptophan to serine.