[A novel human leukocyte antigen-A*33:44 allele revealed by sequence analysis].

OBJECTIVE: To analyze the sequence of a novel human leukocyte antigen (HLA)-A*33:44 allele. METHODS: A novel HLA-A allele was found by double-stranded sequencing combined with single-stranded sequencing. The frequency of the novel allele was determined by population survey. RESULTS: Genomic sequence of this novel HLA-A*33:44 allele (accession No. HQ873871) has differed from HLA-B*33:03:01 by one nucleotide in exon 4, which resulted in nt 866 G→ A substitution, which results in an amino acid substitution from Gly(GGT) to Asp(GAT) at codon 265. This alternation is a new single nucleotide polymorphism compared with other HLA-A alleles. The frequency of this new allele is less than 0.0003 in Chinese Han population. CONCLUSION: A mutation has been found in exon 4 of the novel HLA-A*33:44 allele, which may provide more information for HLA gene study.