A novel human leukocyte antigen-DQ allele, DQB1*0622, was identified in a bone marrow transplantation candidate. DQB1*0622 differs from DQB1*0609 by two nucleotide differences in exon 2, position 122 (A-->T) and 177 (A-->G). The difference at position 122 resulted in an amino acid change (Tyrosine to Phenylalanine). However, the difference at position 177 did not cause any amino acid change.