[A study of HLA-DPA1 and DPB1 matching status for unrelated donor-recipient pairs matched at allele level for HLA-A, -B, -C, -DRB1 and -DQB1 loci].

OBJECTIVE: To analyze the status of HLA-DPA1 and DPB1 matching for unrelated donor-recipient pairs matched at high-resolution allele level for HLA-A, B, C, DRB1 and DQB1 loci. METHODS: A total of 76 unrelated donor-recipient pairs matching at allele level for HLA-A, B, C, DRB1 and DQB1 loci were subjected to HLA-DPA1 and DPB1 sequence-based typing (SBT). HLA-DPA1and DPB1 matching status at high-resolution allelic level was also analyzed. RESULTS: The allelic identity ratio for single HLA-DPA1 and DPB1 were 17.1% and 9.2%, respectively. HLA-DPA1 and DPB1 allelic identity ratio were both very low. The majority of unrelated donor-recipient pairs (73.7%) had an incompatibility at 1 HLA-DPA1 allele, 9.2% of pairs had an incompatibility at 2 DPA1 alleles. As for the high-polymorphic HLA-DPB1 gene, 57.9% of studied donor-recipient pairs had an incompatibility at 1 HLA-DPB1 allele, almost 1/3 (32.9%) of them were completely incompatible. When HLA-DPA1 and DPB1 genes were analyzed together, the donor-recipient pairs matched at 2/4 was the most common (51.4%), 4/4 allelic complete matched pairs accounted for 5.6%, and 0/4 matched pairs accounted for 8.3%. CONCLUSION: Our results indicated that the ratio of HLA-DPA1 and DPB1 complete match in the unrelated donor-recipient pairs matching at allelic level for HLA-A, B, C, DRB1 and DQB1 loci were very low. The effect of HLA-DPA1 and DPB1 matching status on clinical unrelated stem cell transplantation still needs to be elucidated.

[Correlation of killer immunoglobulin-like receptor gene diversity with nasopharyngeal carcinoma in Chinese southern Han population].

The objective of this study was to elucidate the correlation of killer immunoglobulin-like receptor (KIR) gene diversity with nasopharyngeal carcinoma (NPC) in the Chinese southern Han population. KIR genotyping of peripheral blood samples from 67 patients with NPC and 77 randomly-selected healthy controls was performed by PCR-SSP, the relative risk (RR) value was calculated by means of Wolf method. The results showed that the KIR2DL3 gene frequency in NPC patient group was significantly lower than that in healthy controls (χ²>3.84, p < 0.05, RR = 0.08), whereas the KIR2DS5 and KIR2DL5B gene frequencies in patient group were significantly higher than those in healthy controls (χ²>3.84, p < 0.05, RR > 1), the other KIR gene frequencies were no statistically different between two groups. It is concluded that the KIR2DL3, KIR2DS5 and KIR2DL5B genes may be correlated with pathogenesis of NPC in the Chinese southern Han population.

[Demographic characteristics of patients with leukemia waiting for stem cell transplantation in Chinese Marrow Donor Program during 2000 to 2006].

OBJECTIVE: To explore the distributive characteristics for leukemia and to provide scientific reference for its prevention and intervention. METHODS: Microsoft SQL 2005 databases was used to make a mathematical analysis of 3708 patients with leukemia in Chinese Marrow Donor Program (CMDP) from 2000 to 2006. The distributive characteristics were calculated by sex, age and area of patients with leukemia and then compared by constituent ratio and relative ratio statistics method. RESULTS: A total of 3708 cases of leukemia were registered for waiting donor during the period 2000-2006 in CMDP, the age of patients were from 7 months to 69 years, the median age of diagnosis was 24.5 years, standard deviation was 6.7-years-old; males suffered more than females, and the ratio was 1.95: 1 (2451/1257). There were 1202 patients with acute lymphoblastic leukemia (ALL), 1066 with acute myeloid leukemia (AML), 1435 with chronic myeloid leukemia (CML), 5 with chronic lymphoblastic leukemia (CLL), CML was the most common patients. The distributive of 3708 patients with leukemia peak was from 15 to 30 years age group, 542 patients were at the age of 15 years, 559 patients were at the age group above 20 years, 514 patients were at the age above 25, 522 patients were at the age over 30-years-old. ALL patients were accounted for 49.36% (613/1242), AML patients accounted for 27.78% (245/1242), CML patients accounted for 22.78% (283/1242), CLL patients accounted for 0.08% (1/1242) in the age group of under 20 years (childhood group). All subjects were mainly in childhood patients with leukemia; The distributive of patients with leukemia in 30 areas were different, leukemia patients were not registered in one area, 494 patients were at the highest peak, 101 patients were in the median. CONCLUSION: The majority of leukemia patients for waiting stem cell transplantation were registered among children and the adolescents groups, males were suffered more than the females. For children, the major type of leukemia was ALL, being necessary to pay more attention to the education of health, and the precaution of leukemia. The distributive of patients with leukemia for waiting stem cell transplantation was different in 30 areas, and the peak region of leukemia should be in Jiangsu, Guangdong, Shangdong, and Zhejiang provinces.

[Study on the correlation between acute lymphoblastic leukemia and HLA genes in southern China Han population].

To study the correlation between acute lymphoblastic leukemia (ALL) and HLA-A, B and DRB1 gene in southern Chinese Han population and to investigate the susceptible HLA gene to ALL, a total of 4707 healthy volunteer bone marrow donors from southern Chinese Han population were used as a control group, 201 patients diagnosed as patient group from southern Han individuals were genotyped at HLA-A, B and DRB1 loci by PCR-SSP, PCR-SSOP and SBT. HLA allele frequency and its distribution of ALL patient group were compared with the control group by using chi(2) test, and calculated the statistic value of relative risk (RR), pathogenicity score (EF) and preventive score (PF). The results showed that in comparison with the control group, the gene frequence of HLA-A26, B56 and DR9 increased significantly, but the gene frequence of HLA-A30, A33 and B58 allele frequency decreased significantly for patients with ALL. It is concluded that HLA-A26, B56 and DR9 gene have a high correlation with ALL and seem to contribute the genetic susceptibility to ALL in southern Chinese Han populations. However, HLA-A30, A33 and B58 gene seem to have protective role for southern Han individuals suffered from ALL.

[Study of HLA polymorphism in the 6965 Han bone marrow registry donors].

OBJECTIVE: To analyze human leukocyte antigen (HLA) polymorphism and search for new alleles in Chinese Han population bone marrow registry donors. METHODS: DNA-based HLA genotyping methods were used including PCR-SSP, BST and molecular cloning. RESULTS: A total of 6965 unrelated donors, 4707 from South China origin and 2258 from north, were typed for HLA-A, B, and DRB1 loci. Seventy-two specificities of HLA alleles were identified. The HLA-A25, A34, A74, B41, B42, B53, B73 and B81 that were rarely reported in previously Chinese population studies were identified in this study. Estimation of gene frequency indicated that the blank gene frequency was less than 0.2% for HLA-A, 0.25% for HLA-B and 0.70% for HLA-DRB1 loci. Three novel alleles were identified and officially assigned by the World Health Organization (WHO) Nomenclature Committee as A*0253N, A*1114 and B*5610. CONCLUSION: Large-scale DNA-based HLA genotyping used in bone marrow registry donors is highly accurate and reliable for estimating gene frequency and searching for new alleles. The discrepancy of HLA gene distribution between South and North China Han population showed the necessity of setting the more regions in South and North China to screen the bone marrow registry donors for bone marrow transplant.

Development of a DNA-based genotyping method for the Diego blood group system.

BACKGROUND: The paucity of appropriate reagents for serologic typing of the Diego blood group has hindered the identification of the rare Di(b-) blood donors needed to transfuse a Dib antigen-negative patient who presented with anti-Dib. Development of an alternative Di typing approach as a supplement to the current serologic typing method is an important and necessary goal. STUDY DESIGN AND METHODS: DI1 and DI2 alleles result from a single C to T substitution at nucleotide 2561 in exon 19 of the human anion exchanger gene causing a proline (DI1) to leucine (DI2) change at amino acid position 854. Allele-specific primers were designed to specifically amplify the DI1 and DI2 alleles using a PCR-based assay system. RESULTS: A PCR sequence-specific primer (SSP) method for Di genotyping was developed, and the specificity and reproducibility of the method were assessed in a blind control study using serologic tests, family segregation, and DNA sequencing analyses. A total of 1,766 DNA samples from unrelated blood donors were typed for DI1 and DI2 alleles and a single Di(b-) donor was identified. The frequency of DI1 and DI2 alleles among Chinese blood donors was 0.0357 and 0.9643, respectively. CONCLUSION: A simple, accurate, and inexpensive DNA-based PCR-SSP method was established for Di genotyping. The typing results can be visualized on a single photograph within 3 hours, making this reliable method suitable for large-scale typing of potential blood donors without serologic backup.