Genetic analysis of a Chinese pedigree with an allele dropout at the HLA-B locus / 中华医学遗传学杂志

OBJECTIVE@#To delineate a deletional mutation of the HLA-B gene in a Chinese pedigree.@*METHODS@#A female patient with acute myeloid leukemia who had visited Liuzhou People's Hospital in April 2022 was selected as the study subject. Routine human leukocyte antigen (HLA) was determined by using PCR-sequence specific oligonucleotide polymorphism (PCR-SSOP) and PCR-sequence-based typing (PCR-SBT) methods. Next generation sequencing (NGS) was used to validate the candidate variant in the HLA-B gene.@*RESULTS@#The PCR-SBT and SSOP results for the HLA-B locus were inconsistent for the patient and her daughter. The SSOP results of the two individuals were HLA-B*35:01, 40:02 and HLA-B*35:01, 40:01, respectively. However, the PCR-SBT results has indicated a mismatch with the nearest HLA-B*35:01 at exon 4. NGS results showed that the HLA-B*35:01 had a 9 bp deletion in the intron 5. The patient's husband was HLA-B*40:01, 58:01, which was normal.@*CONCLUSION@#The variant in intron 5 of the HLA-B gene in this pedigree has mapped to a primer-binding region for the SBT reagent, which has affected the accuracy of PCR-SBT results.

Analysis of genetic polymorphisms and a novel tri-allelic cloning sequence for the D13S317 locus among an ethnic Han Chinese population / 中华医学遗传学杂志

OBJECTIVE@#To study the genetic polymorphisms of short-tandem repeats (STR) for the D13S317 locus among an ethnic Han Chinese population and verify a novel tri-allelic pattern identified for the locus.@*METHODS@#A total of 378 paternity test cases from Guangdong Forensic Authentication Institute from October 17, 2017 to December 28, 2017 were selected as the study subjects. A GlobalFilerTM Express kit was used for the STR genotyping. Samples suspected for having a novel tri-allelic pattern were verified with a PowerPlex 21 kit. Potential variant of the primer-binding region and flanking sequences underlying the tri-allelic pattern was excluded by molecular cloning and sequencing.@*RESULTS@#Six alleles were detected for the D13S317 locus, with the characteristic distribution frequencies being 8 (29.1%), 9 (13.1%), 10 (15.21%), 11 (24.21%), 12 (13.89%) and 13 (3.44%), respectively. In one of the families, the D13S317 locus of the proband was suspected to harbor a triband allele (8, 9, 10). A re-test has confirmed the result of initial test. Molecular cloning and sequencing analysis of the D13S317 locus in the proband and his daughter has failed to find allelic variants in the primer-binding region and flanking sequence, which has confirmed the novel tri-allelic pattern for the locus.@*CONCLUSION@#A novel type 2 tri-allelic pattern (8, 9, 10) at the D13S317 locus has been identified among the ethnic Han Chinese population. The pattern has not been transmitted to the female offspring, and has been included in the international STRBase database for the first time.

Polymorphisms of MICA gene and their linkage disequilibrium with HLA-B among ethnic Han Chinese from Shenzhen / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study the distribution of MICA alleles among ethnic Han Chinese blood donors from Shenzhen and their linkage disequilibrium with HLA-B gene.</p><p><b>METHODS</b>For 143 randomly selected blood donors, the MICA and HLA-B alleles were determined with a PCR-sequence based typing (SBT) method. Allelic frequency, haplotypic diversity and linkage disequilibrium were analyzed with a Pypop software.</p><p><b>RESULTS</b>Thirteen MICA and 35 HLA-B alleles were identified among the 143 blood donors, among which MICA*008:01 had the highest frequency (76/286), whilst MICA*008:01-HLA-B*40:01 and MICA*010-HLA-B*46:01 were the most common haplotypes. No novel allele was identified.</p><p><b>CONCLUSION</b>The allele frequencies, haplotype diversities and linkage disequilibrium parameters under a high resolution can facilitate further studies and applications of the MICA and HLA-B genes.</p>

Accurate determination of HLA ambiguous results based on group-specific haploid full-length sequencing / 中国组织工程研究

BACKGROUND: Due to the polymorphism of HLA, a large number of ambiguities have been generated by conventional HLA typing techniques, and confirmed stereotypes of ambiguous results based on group-specific haploid full-length typing are rarely reported.OBJECTIVE: To analyze the accuracy of HLA-typing ambigulity based on group-specific haploid full-length sequencing. METHODS: The low-resolution results were used as the starting point for two ambiguous samples. Sanger sequencing (PCR-SBT) based on haploid full-length was performed after group-specific amplification. RESULTS AND CONCLUSION: One case showed a new A*02:03:01 allele, which was found a mutation in NT817 from C to T in comparison with A*11:01:01:01. The other case indicated another new C*07:02:01:01, which was found a mutation in NT879 from A to G in comparison with C*08:01:01. In conclusion, these results indicate that the group-specific haploid full-length sequencing method can be used to accurately classify HLA alleles and to discover new alleles.

Identification of genomic full-length sequence of human leukocyte antigen-E and its two novel alleles / 中国组织工程研究

BACKGROUND: Human leukocyte antigen-E (HLA-E) is one of non-classical HLA class I genes. Up to now, the polymorphism analysis is mainly aimed at the variation in exon 3 of HLA-E, which determines HLA-E*01:01 or HLA-E*01:03. However, the identification of the full-length HLA-E and its novel alleles is rare reported.OBJECTIVE: To establish the method of identification of HLA-E genomic full-length sequence, and to identify its novel alleles in healthy blood donors in Shenzhen, China.METHODS: Peripheral blood DNA samples were extracted from the subjects, and the amplified primers and sequencing primers in conserved regions were designed according to the sequences of HLA-E published in the IMGT/HLA database.A high-fidelity reaction system was used to amplify the genomic full-length of HLA-E, followed by sequencing,assembling, confirming and typing.RESULTS AND CONCLUSION: Herein, we successfully established the method for amplifying genomic full-length sequence and sequence-based typing. Two novel HLA-E alleles were nominated by WHO HLA Nomenclature committee as HLA-E*01:01:01:06 and HLA-E*01:01:01:07. Compared with the most related allele HLA-E*01:01:01:01,HLA-E*01:01:01:06 had one nucleotide change at nt-26(G->T) in 5'-promoter, and HLA-E*01:01:01:07 had one nucleotide change at nt3345(T->C) in 3'-UTR. The polymorphism data of genomic full-length HLA-E in Chinese individuals need to be filled, and the method we developed here supplies the key technique for the further studies.

Genetic polymorphisms of KIR2DS4 gene among ethnic Hans from southern China / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study genetic polymorphisms of the KIR2DS4 gene among ethnic Hans from southern China.</p><p><b>METHODS</b>Genomic DNA was isolated from 306 unrelated individuals and amplified with KIR2DS4-specific PCR primers. KIR2DS4-positive samples were genotyped for the entire coding sequence by sequencing-based typing (SBT). Assignment of allelic genotypes was accomplished by using Assign 3.5 software. For samples with inconclusive SBT results, RT-PCR products covering the entire coding sequence of the KIR2DS4 gene were subjected to cloning and haplotype sequencing.</p><p><b>RESULTS</b>Among all tested samples, 297 were demonstrated to have carried the KIR2DS4 framework gene. For KIR2DS4-positive samples subjected to SBT for the entire coding sequences, no background was observed with the obtained sequences. Three of the seven identified alleles were of novel types, which were officially named by the KIR subcommittee of the World Health Organization Nomenclature Committee for Factors of HLA System. The observed frequencies for the 7 alleles were KIR2DS4*00101 (78.8%), *003 (10.5%), *004 (16.0%), *010 (23.2%), *017 (0.3%), *00105 (0.3%) and *018 (0.7%), respectively. Allele KIR2DS4*007 was not found. The overall frequency for normal cell-surface expression KIR2DS4 alleles including 2DS4*00101, *017 and *00105 was 79.4%, and that for non cell-surface expression alleles including 2DS4*003, *004, *010 and *018 was 50.4%. The ratio between the two was 1.6:1.</p><p><b>CONCLUSION</b>The present study has elucidated the allelic diversity of KIR2DS4 among ethnic Hans from southern China, which may provide valuable data for transplantation as well as studies on KIR-associated disease and evolution.</p>

Association of genetic polymorphisms of KIR-HLA system with chronic myeloid leukemia among ethnic Hans from southern China / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the association of KIR-HLA gene polymorphism with chronic myeloid leukemia (CML) among ethnic Hans from southern China.</p><p><b>METHODS</b>A total of 172 adult CML patients and 480 unrelated healthy controls were screened for the presence of KIR with sequence-specific primers-PCR (PCR-SSP) and sequence-based typing (SBT) of HLA-A, -B and -C loci. Polymorphisms of the KIR-HLA system were analyzed at 4 levels, and the frequencies of KIR framework genes and KIR profiles, classⅠHLA ligands, matched KIR+HLA pairs and KIR-HLA compound profile were compared between the two groups. P values were calculated using SPSS 13.0 software.</p><p><b>RESULTS</b>For the CML group, the frequencies of HLA-C2 ligand, 2DL1+HLA-C2 pair and HLA-B Bw4-80I were significantly lower than those of the control group, suggesting a protective effect against CML (HLA-C2: OR=0.386, 95%CI:0.240-0.620, P<0.01; 2DL1+HLA-C2: OR=0.316, 95%CI:0.191-0.525, P<0.01; HLA-B Bw4-80I: OR=0.576, 95%CI:0.384-0.862, P<0.01). The frequencies of KIR2DL1 ligand (HLA-C2) and KIR3DL1 ligand (HLA-B Bw4-80I) in the CML group were significantly lower than that of the control group, suggesting that the HLA-C2 and HLA-B Bw4-80I expression is probably decreased in the CML patient group, which led to reduced inhibitory signal and enhanced activating signal of KIR2DL1and/or KIR3DL1NK cells. Notably, the frequency of KIR-HLA compound profiles ID2 (KIR AA1-HLA-C1/C1-Bw6/Bw6-A3/11) in CML patients significantly increased in the CML patient group compared with the control group, suggesting that the KIR-HLA compound profiles ID2 may be a risk factor for CML (OR=2.163, 95%CI 1.198-3.906, P<0.01).</p><p><b>CONCLUSION</b>Above analysis has identified certain protective and risk factors for CML from the KIR-HLA system, which may provide a clue for the pathogenesis of leukemia and development of individualized immune therapy.</p>

Study of polymorphisms of HLA class Ⅰ (-A, -B, -C) and class Ⅱ (DRB1, DQA1, DQB1, DPA1, DPB1) genes among ethnic Hans from Southern China / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study the genetic polymorphisms of human leukocyte antigen (HLA)- A, B, C, DRB1, DQA1, DQB1, DPA1and DPB1among ethnic Hans from southern China.</p><p><b>METHODS</b>481 randomly selected individuals were genotyped using a polymerase chain reaction (PCR) sequence-based typing (SBT) method for the above genes. Their allele frequencies were determined by direct counting.</p><p><b>RESULTS</b>In total, 28 HLA-A, 57 HLA-B, 28 HLA-C, 40 HLA-DRB1, 18 HLA-DQA1, 17 HLA-DQB1, 6 HLA-DPA1and 21 HLA-DPB1alleles were identified. Among these, common alleles (with allelic frequencies > 0.05) included A*1101, A*2402, A*0207, A*3303, A*0201, B*40:01, B*46:01, B*58:01, B*13:01, B*15:02, C*01:02, C*07:02, C*03:04, C*03:02, C*08:01, C*03:03, C*04:01, DRB1*09:01, DRB1*15:01, DRB1*12:02, DRB1*08:03, DRB1*03:01, DRB1*04:05, DRB1*11:01, DQA1*01:02, DQA1*03:02, DQA1*03:03, DQA1*06:01, DQA1*01:03, DQA1*05:05, DQA1*01:04, DQA1*03:01, DQA1*05:01, DQB1*03:01, DQB1*03:03, DQB1*06:01, DQB1*05:02, DQB1*03:02, DQB1*02:01, DQB1*03:02, DQB1*06:02, DPA1*02:02, DPA1*01:03, DPA1*02:01, DPB1*05:01, DPB1*02:01, DPB1*13:01, DPB1*04:01and DPB1*02:02.For each of the locus, the overall frequencies of common alleles were 75.57%, 52.81%, 78.28%, 62.16%, 86.70%, 77.23%, 95.32% and 81.59%, respectively.</p><p><b>CONCLUSION</b>The allelic frequencies of the 8 selected HLA loci among ethnic Hans from southern China may served as a reference for anthropology, legal medicine, transplantation and disease association studies.</p>

Analysis of ambiguities in HLA sequencing-based typing and its solutions / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the number and ratio of ambiguous allele combinations from human leukocyte antigen (HLA) confirmatory test by sequencing based typing for unrelated donor marrow transplantation, and to establish an efficient strategy for identifying such ambiguities.</p><p><b>METHODS</b>A total of 650 donor-receipt samples were genotyped for 5 loci of the HLA gene using an Atria SBT commercial kit. Exons 2, 3 and 4 of HLA-A, -B and -C, exon 2 of HLA-DRB1 and exons 2 and 3 of HLA-DQB1 were tested by routine HLA genotyping. The ratio of usual ambiguous allele combination was calculated. The ambiguities were subjected to further confirmatory test by PCR-SSP or PCR-SBT retest at outside of the routine sequencing region.</p><p><b>RESULTS</b>Among the 650 tested samples, the ratio of ambiguity at HLA-A, B, C, DRB1 and DQB1 were 76.31% (496/650), 91.08% (592/650), 97.69% (635/650), 88.62% (576/650) and 43.38% (141/650), respectively. A total of 36 ambiguous allele combinations inside the routine sequencing region and 22 ambiguous allele combinations outside of the routine sequencing region were discovered. After removing rare alleles based on the Chinese common and well documented (CWD) Allele Table (Version 1.01), 9 ambiguous CWD allele combinations inside the routine sequencing region, including 3 located in HLA-B, HLA-C and 1 located in other three HLA loci were found. Ten ambiguous CWD allele combinations outside of the routine sequencing region, including 4 located in HLA-C, -DRB1 and 1 in HLA-A, -B respectively were determined. All samples with ambiguous CWD allele combinations could be distinguished by high-resolution PCR-SSP commercial kits or PCR SBT retest at outside of the routine sequencing region.</p><p><b>CONCLUSION</b>The common and well documented allele combinations in sequencing-based typing at five HLA loci have been analyzed. Our strategy may provide valuable information for more efficient, low cost and accurate method for high resolution genotyping of HLA genes.</p>

Association of HLA-DPA1 and -DPB1 polymorphisms with Posner-Schlossman syndrome among southern Chinese Han population / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To assess the association of HLA-DPA1 and -DPB1 polymorphisms with Posner-Schlossman syndrome (PSS) in southern Chinese Han population.</p><p><b>METHODS</b>A total of 100 randomly selected PSS patients of southern Chinese Han origin were served as the experimental group, while 128 unrelated healthy blood donors of the same origin were served as the control group. All samples were subjected to sequencing-based typing (SBT) for exon 2 of HLA-DPA1 and -DPB1 loci in both directions. HLA genotype was assigned using an Assign 3.5 HLA SBT software. The allele frequencies and haplotype frequencies of HLA-DPA1 and -DPB1 of the two groups were compared. x² test, P value and odds ratio (OR) value were calculated.</p><p><b>RESULTS</b>Six HLA-DPA1 alleles in the experimental group and 4 HLA-DPA1 alleles in the healthy control group were identified. The allelic frequency for HLA-DPA1*02:01 in the experimental group was significantly lower than the control group (4.50% vs. 12.109%; x²=8.124, P=0.004). Sixteen HLA-DPB1 alleles were identified in both the experimental and control groups. The allelic frequencies for HLA-DPB1*14:01 and - DPB1*17:01 in the experimental group were significantly lower than those of the control group ( DPB1*14:01: 1.00% vs. 4.688%, x²=5.130, P=0.024; DPB1*17:01: 0% vs. 2.344%, x²=3.897, P=0.048). The DPA1-DPB1 haplotypes for the experimental and control groups were 23 and 25, respectively. The haplotype frequencies for both DPA1*02:01- DPB1*14:01 and DPA1*02:01- DPB1*17:01 were significantly lower than those of the control group.</p><p><b>CONCLUSION</b>DPA1*02:01- DPB1*14:01 and DPA1*02:01- DPB1*17:01 haplotypes may provide considerable protection effect against PSS in the southern Chinese Han population.</p>

Sequence analysis of a novel allele HLA-C*01:78 / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the genetic basis for a novel allele HLA-C*01:78.</p><p><b>METHODS</b>Genomic DNA was extracted from peripheral blood using a QIAGEN quick DNA extraction kit. The regions encompassing HLA-C from exon 1 to intron 3 and intron 3 to 3'UTR were amplified and cloned using a cloning sequencing kit in order to split the two alleles apart. Selected clones were sequenced to include exons 2 to 4.</p><p><b>RESULTS</b>Sequencing results have indicated the HLA-C alleles of the proband to be a novel C*03:04 allele. The sequence has been submitted to GenBank (KF049216). BLAST analysis has confirmed the novel allele to have one nucleotide difference as C*01:03 at genomic nt316C>A (codon 82CGC>AGC) in exon 2, which has resulted in replacement of one amino acid (82R>S).</p><p><b>CONCLUSION</b>The novel allele has been officially named as C*01:78 by the WHO Nomenclature Committee. The HLA allele type of the proband was therefore A*02:07, 24:02; B*40:01, 46:01; C*01:78, 03:04; DQB1*05:02, 05:02; DRB1*16:02, 16:02.</p>

Result analysis of four human leukocyte antigen rare alleles / 中国组织工程研究

BACKGROUND:Many articles concerned novel al eles reported in China and outside China, but some al eles were detected lately. After that, these al eles were tested again. Because frequencies of these al eles are very low, few relevant articles are reported, so these al eles are ignored easily. OBJECTIVE:To test and identify four human leukocyte antigen rare al eles that patients and donors carries. METHODS:Genomic DNA was extracted automatical y from blood samples using quick DNA purified kit, typed by human leukocyte antigen locus commercial sequence-based typing kits and confirmed by sequence-specific primers high-resolution kits. RESULTS AND CONCLUSION:Four detected rare al eles are B*27:15, B*51:39, C*07:66 and C*08:22. The four above-mentioned human leukocyte antigen rare al eles defined by National Marrow Donor Program are not rare in China. The facts prove that C*08:22 which was defined a rare al ele by National Marrow Donor Program before is a common al ele in Chinese Han nationality.

STUDY ON THE ANTITUMOR EFFECT AND IMMUNE MODULATION OF EXTRACT FROM CHLORELLA PYRENOIDOSA CHICK / 营养学报

Objective: To study the antitumor activity and immune modulation of extract from Chlorella pyrenoidosa Chick. (CE). Methods:Cyclophosphamide is positive control and saline is negative control. S180-bearing and HCA-bearing mice were used as animal model. The changes of the growth of S180 and HCA tumor cells in vitro, the changes of tumor weight in vivo and the effect on immune system such as phagocytosis of macrophages,proliferation of lymphocytes were investigated when CE were used. Results: The tumor cells were killed by CE in vitro. CE inhibited tumor growth markedly in S180 and HCA bearing mice and the effect was enhaced if CE and cyclophosphamide were used simultaneously. CE also enhanced the immune function. Conclusion: CE has the antitumor effect and the effect of immune modulation.