ABSTRACT
Objective To analyze the frequencies of HLA-DQA1 alleles and their clinical values in the donor-recipient HLA-A,-B,-C,-DRB1,-DQB1 (10/10) matched hematopoietic stem cell transplantation (HSCT).Methods This study recruited 127 patients who received allogeneic HSCT and 127 unrelated donors.High-resolution (High Res) DNA typing for HLA-DQA1 alleles were performed on the 254 subjects by using sequence specific oligonucleotide probes (SSOP) and high resolution of sequence specific primer(High Res SSP).Results The DQA1 allele genotypes of 36 pairs of donor-recipient were directly identified by using SSOP.The ambiguous DQA1 allele genotypes of the rest 91 pairs were identified by using High Res SSP.Among the 127 pairs of donor-recipient,5 pairs were HLA-DQA1 alleles mismatched,while the others were all matched.No significant differences in the distribution of HLA-DQA1 alleles were observed between the donors and the recipients.Sixteen HLA-DQA1 alleles were detected in the 127 donors,which were DQA1 * 02 ∶ 01 (19.3％),DQA1* 01 ∶ 02(19.3％),DQA1 * 03 ∶ 02/03 (17.0％),DQA1 *01∶03 (9.8％),DQA1*06∶01(9.1％),DQA1*05∶ 01(7.1％),DQA1*05∶05(5.9％),DQA1*03∶01 (4.7％),DQA1*01 ∶04(2.4％),DQA1*01∶05(2.0％),DQA1*01∶01(1.2％),DQA1*05 ∶ 03(0.8％),DQA1 *05 ∶ 08(0.8％),DQA1*04 ∶ 01(0.4％),DQA1*05 ∶ 06(0.4％) from high to low frequency.Moreover,a new allele was detected in the patients.The haplotypes' frequencies and linkage disequilibrium(LD) analysis of HLA-DQA1 and HLA-DQB1 showed that the most common haplotype was DQA1 *02 ∶ 01-DQB1 *02 ∶ 02(16.1％),followed by DQA1 *03 ∶ 02/03-DQB1 *03 ∶ 03 (11.8％)and DQA1 *01 ∶ 03-DQB1 * 06 ∶ 01 (9.1％).Stronger LD were observed between DQA1 * 02 ∶ 01 and DQB1*02 ∶ 02,DQA1 *03 ∶ 02 and DQB1*03 ∶ 03,DQA1 *01 ∶ 03 and DQB1*06 ∶ 01,HLA-DQA1*06∶01 andDQB1*03 ∶ 01,DQA1*05 ∶ 01 and DQB1*02 ∶ 02(P＜0.001).Conclusion There was strong linkage disequilibrium between HLA-DQA1 and HLA-DQB1 genes.The polymorphism of HLA-DQA1 gene was less than that of HLA-DQB1 gene.No more guidance was provided to donor selection in unrelated donor-recipient HLA matched HSCT by adding HLA-DQA1 genotyping,but it might have clinical application values in HSCT with HLA Ⅱ locus mismatched donor and recipient.
ABSTRACT
Objective:To seek for susceptible and protective gene of GD by analyzing the allele frequency distribution of HLA-DQA1 loci and to evaluate the association of HLA-DQA1 gene polymorphism with GD pathogenesis in Chongqing children of Han race.Methods:Eighty-five children with GD [including 21 boys and 64 girls,mean age (8.84?2.51)] and 50 racially matched healthy controls were recruited for the study.Both groups were of Han race.Genomic DNA was extracted from venous blood samples.Genotypes of HLA-DQA1 were detected by polymerase chain reactions with single strand conformation polymorphism (PCR-SSCP).The results were identified by DNA sequence typing.Frequencies of HLA-DQA1 alleles at eath locus were compared between patients and controls using the ? 2 -test.Results:7 kinds of HLA-DQA1 conformations were found in 85 GD and 50 healthy controls, respectively marked with a b c d e f g.Compared with control group,the frequencies of d and f conformation increased significantly [43.5% VS 8%, ? 2=18.79,P=0.001, relative risk(RR)=8.86;27% VS 8%, ? 2=6.80,P =0.009,RR=4.27],and the frequency of b conformation decreased significantly (8.2% vs 52%, ? 2=29.43,P=0.001, RR=0.08) in GD group.DNA sequence analysis showed that d conformation was HLA-DQAl*0102, f conformation was HLA-DQAl*0302/0501,b conformation was HLA-DQA1*0101/0301.Conclusion:The polymorphism of HLA-DQA1 loci in Chongqing children of Han race are different from that of Caucasian,American Black,Japanese and Hongkong Chinese. It shows that different race and area have different alleles.GD is significantly associated with HLA-DQA1*0102, HLA-DQA1*0302/0501 and HLA-DQA1*0101/0301.It suggests that the HLA-DQA1*0102 and HLA-DQA1*0302/0501 might be the genetic markers for susceptibility, HLA-DQA1*0101/0301 might be the protective genetic markers for GD in Chongqing children of Han race.