Seventy-eight novel HLA class I and II alleles identified during routine registry typing in 2008 and 2009

Seventy-eight novel human leukocyte antigen (HLA) class I and class II alleles are described: 19 HLA-A alleles, 30 HLA-C alleles, 21 HLA-B alleles, 7 HLA-DRB1 alleles and 1 HLA-DPB1 allele. Eight (∼10%) of the novel alleles were found in more than one individual and may be more common in the population. Sixty-two (∼80%) of the 78 novel alleles are single nucleotide substitution variants when compared with their most homologous allele. Twelve of these single nucleotide variants are silent substitutions and one creates a null allele (C*08:26N). One of the novel HLA-C alleles, C*03:58, is a hybrid that likely resulted from an intra-locus recombination. The remaining novel alleles differ from their most similar allele by two to seven nucleotide substitutions. Four of the novel HLA-C alleles encode amino acid changes at codons 41, 42, 55 or 200 which have not previously been reported to be polymorphic. Some of the new alleles encode novel codons and unique amino acid changes at polymorphic positions in the HLA-A (codons 55 and 120), HLA-C (codons 151, 153 and 176), HLA-B (codons 31 and 84) and HLA-DRB1 (codon 47) loci.