RESUMO
This study was purposed to investigated and analyze the allelic frequency of a common allele HLA-C*08:22 in the southern Chinese Han population. A total of 32 samples with the C*08:01:01/08:22 ambiguous results previously identified in 163 unrelated southern Chinese Han population by routine sequencing based typing (SBT) at exons 2 - 4 of HLA-C gene were subjected to HLA-C SBT at exons 5 and 6 using our in-house method. Forty C*08:01:01-positive unrelated donor/recipient pair identified before the C*08:22 allele were officially nomenclatured and released by the World Health Organization (WHO) Nomenclature Committee for Factors of HLA System, were re-sequenced at exons 2 - 6 of HLA-C gene by our in-house SBT method. The allele assignment was accomplished with the Assign 3.5 SBT software. The results showed that three samples were identified as C*08:22-positive in the 32 samples with C*08:01:01/08:22 ambiguous results, the allele frequency of C*08:22 was 0.92% in the southern Chinese Han population. Retrospective analysis indicated that 2 donor/recipient pairs previously identified as C*08:01:01-positive were actually C*08:22-positive in the 40 tested donor/recipient pairs. It is concluded that the novel C*08:22 allele is the common allele in southern Chinese Han population, it can't be considered as rare allele and is ruled out for the samples with C*08:01:01/08:22 ambiguous results.