P121 Linkage disequilibrium between specific HLA-DPB1 alleles and a single nucleotide polymorphism RS9277534 in a Southern Chinese population

Abstract

Aim A single nucleotide polymorphism(SNP), rs9277534, within the 3′untranslated region of HLA-DPB1 has been shown to be involved in the regulation of HLA- DPB1 expression. The risk of graft-versus-host disease(GVHD) associated with HLA-DPB1 mismatching was influenced by the HLA-DPB1 rs9277534 expression marker. We investigate the linkage disequilibrium(LD) between specific HLA-DPB1 alleles and rs9277534 SNP in Chinese Sichuan Han individuals, and provide valuable genetic information for clinical transplantation. Methods We collected 200 blood samples from Sichuan Han population. After DNA extraction, samples were genotyped for HLA-DPB1 and rs9277534 by polymerase chain reaction sequence-based typing. Results The results showed that DPB1∗05:01:01G allele was the most common which the frequency was 0.4125 in Sichuan Han Population. AA, GG and AG of SNP genotype frequencies were 0.165, 0.375 and 0.46. The allele frequencies of A and G were 0.4 and 0.6. There are 35 HLA-DPB1 alleles present in the Sichuan Han population, 10 were found to be in significant LD with the rs9277534 SNP. The DPB1∗04:02:01G, DPB1∗02:01:02G, DPB1∗02:02:01G and DPB1∗17:01:01G were in complete linkage with the rs9277534A allele, while DPB1∗05:01:01G, DPB1∗03:01:01G, DPB1∗13:01:01G, DPB1∗14:01:01G and DPB1∗21:01, were in complete LD with the rs9277534G allele (p 0.05). While not completely, DPB1∗04:01:01G (D′ = 0.95; p 0.01) were found to be in significant LD with the rs9277534A allele. Conclusions These findings provide valuable scientific basis for clinical transplantation for reasonable choice between donor and recipient in a Han Southern Chinese population. If recipients with HLA-DPB1 alleles for DPB1∗05:01:01G, DPB1∗13:01:01G and DPB1∗21:01, and they accept hematopoietic stem cell of donors which HLA-DPB1 alleles for DPB1∗04:01:01G,DPB1∗04:02:01G, DPB1∗02:01:02G and DPB1∗02:02:01G, even if donor-recipient pairs as permissive according to T cell epitope(TCE) algorithm, which may also increase the risk of GVHD. Download : Download high-res image (635KB) Download : Download full-size image