Recombination within the HLA-D region. Correlation of molecular genotyping with functional data

Molecular genotyping of the HLA-D/DR region in a family correlated with serologic and cellular typing data. It was further possible to predict a subtle difference in SB region-related functions from such molecular studies. A family that included an individual who inherited an HLA haplotype with a paternal recombination between HLA-B and the HLA-D/DR region was identified by classic HLA typing techniques. Segregation of HLA-D/DR region genes in this family was studied by Southern blot analysis using cDNA probes for DR alpha, DR beta, DC alpha, DC beta, and SB beta. Restriction enzyme fragment polymorphisms observed for every gene tested were in concordance with assigned HLA haplotypes (including the individual known to have inherited a paternal recombinant haplotype) with one exception: two HLA identical siblings were observed to have different SB beta restriction fragment patterns. Further testing revealed that one individual inherited a maternal HLA haplotype recombinant between the HLA-D/DR region and SB beta. Although both maternal SB alleles typed as SB4, allelic differences could be detected cellularly by primed lymphocytes and by the differential expression of a class II cell surface antigen using monoclonal antibody. Therefore, predicted and nonpredicted recombinant haplotypes were detected in a family by molecular genotyping.     

DNA序列分析鉴定HLA新等位基因B~*0740

目的确认一个中国人群中的新HLA等位基因。方法应用单倍型特异性分离(haplotype-specific ex-traction,HSE)技术和DNA序列分析技术鉴定HLA-B~*的新等位基因。结果被检标本HLA-B位点有一个等位基因的核苷酸序列与任何已知的HLA等位基因均不同,与同源性最高的B~*0705相比,在exon3区域中的605位碱基由A>T,引起编码178位的氨基酸由赖氨酸(K)变成甲硫氨酸(M)。血清学分型表明新等位基因的免疫学表型仍为HLA-B7。家系分析提示,HLA-B~*0740基因来源于其母亲。结论该等位基因序列为HLA-B位点的一个新等位基因,于2005年2月由WHO HLA因子命名委员会正式命名为HLA-B~*0740。     

Dispermic chimerism identified during blood group determination and HLA typing

BACKGROUND: Chimerism is the presence of two or more genetically distinct cell populations in one organism. STUDY DESIGN AND METHODS: We report the identification of dispermic chimerism in a 19-year-old female volunteer blood donor. During routine ABO blood grouping strong reactions of the blood donors red blood cells (RBCs) with anti-A reagents and mixed-field reactions with anti-B reagents were observed, while serum-testing showed the absence of anti-A and anti-B antibodies. AB0 blood group genotyping, HLA-typing and microsatellite analysis were performed using blood-samples, buccal mucosa and fibroblasts of the blood-donor and blood-samples of her parents. RESULTS: AB0 blood group genotyping showed three ABO blood group alleles (0(1), A(2) and B) in the DNA-samples of the blood-donor. The evidence of chimerism was supported by the detection of three alleles for the HLA-A and HLA-DRB1 loci. Microsatellite analysis with ten markers revealed three alleles for loci D7S821 and D19S412. All studies carried out, the third allele was always of paternal origin. CONCLISION: The results suggested a case of a human dispermic chimerism. Our proposed explanation for the development of chimerism in the reported case is the fertilization of an oocyte and the corresponding second polar body by two different sperms.     

Tetragametic chimerism detected in a healthy woman with mixed-field agglutination reactions in ABO blood grouping

BACKGROUND: The case of a healthy woman with serologic blood group AB and her biologic father showing blood group O was investigated. Further analysis, including blood, buccal swabs, and nail clippings, revealed a tetragametic chimerism. STUDY DESIGN AND METHODS: Blood grouping was performed with standard gel centrifugation test cards, ABO genotyping by sequence-specific primers (SSPs) and sequence-based typing, and HLA Class I and II typing by standard NIH cytotoxicity testing and SSP. Additionally, short-tandem-repeat (STR) and variable-number tandem-repeat (VNTR) typing was performed on blood, nail clippings, and buccal swab samples. The karyotype was analyzed by G-banded chromosomes. RESULTS: The proposita's RBCs were typed AB with a mixed-field agglutination whereas in molecular typing A, B, and O alleles were found. One paternal and two maternal haplotypes were determined by use of HLA typing. Interestingly, both paternal alleles were detected in 4 of 23 tested STR and VNTR loci only, with whole blood, nail clippings, and buccal swabs. The karyotype was identified as 46XX. The family members including the proposita's healthy twin children displayed no abnormal findings in tests performed. CONCLUSION: By investigation of DNA polymorphisms, it was possible to determine a rare case of tetragametic chimerism being the result of double parental contribution of nuclei.     

中国北方汉族骨髓供者HLA-B＊15组基因多态性的PCR-SBT分型研究

为了研究中国北方汉族骨髓供者HLA—B＊15等位基因的分布特征，探讨其可能对临床供体选择的影响，从中华骨髓库陕西分库内随机抽取815名已知低分辨分型结果中国北方汉族骨髓供者，采用聚合酶链反应-碱基序列直接测序（PCR—SBT）方法对其中206例HLA—B＊15阳性样本和另外附加17例样本进行HLA—B位点DNA测序分析，并应用同源模建分子模拟技术对所有结果模拟出三维结构，用计算机软件Swiss—PdbViewer比较模拟结构间的差异大小。结果表明：随机抽取的815例样本HIJA—A、B、DRB1基因分布符合Hardy—Weinberg平衡定律，HIJA—B＊15基因频率为0．1379，总共检出16种HIJA—B＊15等位基因，分属7种血清学特异性，以B＊1501、B＊1511、B＊1502和B＊1518为主，频率分别为0．0485、0．0215、0．0178和0．0160，累计频率构成比占全部B＊15的75．11％，其余12种B＊15等位基因频率均〈0．0100。19例HIJA—B＊15，-测序分析表明，其中10例中低分辨水平上的纯合子中仅4例为真正意义上的B＊15xx，-纯合子，且均由各自优势基因构成。三维结构模拟分析发现同一血清型中既存在结构差异微小的等位基因，如B＊1501、1505、1507、1525、1527、1532（RMSD≤0．02nm），也存在差异较大的等位基因，如B＊1502、1511、1521之间以及B＊1503、1546之间（RMSD均为0．29nm），而一些分属不同血清型的等位基因之间结构却近似（RMSD值≤0．02nm）。结论：本研究应用PCR—SBT，首次取得了中国北方汉族样本量最大的高分辨水平HLA—B＊15基因多态性分布特征，这将有助于临床患者寻找合适供者，并为移植免疫及本地区群体遗传学等方面的研究提供了重要依据，且对于临床选择最适供者，像HLA—B＊15这样血清学特异性及基因亚型高度多态性的家族进行准确的高分辨分型是必要的。     

一个罕见HLA-C等位基因间重组家系的遗传背景研究

目的 研究HLA-C等位基因座位上的交换重组,探讨HLA新等位基因产生的分子遗传背景.方法 采集拟进行造血干细胞移植的1例慢性粒细胞白血病患者、患者父母以及2名哥哥的静脉血,采用AlleleSEQR HLA 测序分型试剂进行HLA-A、C、B、DRB1和DQB1共5个位点的高分辨基因分型;再采用Protrans S4 HLA单倍体测序技术分离2个HLA-C等位基因,以确定序列异常的1个C等位基因;进一步采用分子克隆和测序方法进行患者及父母HLA-C等位基因的全长单倍体序列分析.按遗传规律分析该家系的HLA 5个位点的连锁单倍型,同时将HLA-C等位基因全长序列经IMGT/HLA Database中的"BLAST"程序进行序列的对比,以确定C等位基因重组发生的精确位置.结果 经HLA测序及遗传家系分析,该家系中父亲的2条HLA连锁单倍型分别为a:A*0207-C*010201-B*550201-DRB1*090102-DQB1*030302与b:A*240201-C*120202-B*5201-DRB1*1502-DQB1*0601;母亲的分别为:c:A*300101-C*060201-B*130201-DRB1*0405-DQB1*0401与d:A*110101-C*070201-B*4001-DRB1*080302-DQB1*0601.患者的2名哥哥均分别正常遗传了父母的2条单倍体a、d及b、c.患者的2条单倍体分别为母源单倍体c及父源重组单倍体a/b,其中A*240201来自父亲的1条染色单体b,而B*550201-DRB1*090102-DQB1*030302则来自父亲的另1条染色单体a.对比患者携带的C未知新等位基因与父亲的1对C*010201 、C*120202等位基因的全长单倍体序列,推断父亲的2条染色单体在减数分裂时,由于HLA-C等位基因的第273位至330位碱基区域之间发生了交换,重组后形成新的C等位基因及单倍型并遗传给了患者.该C新等位基因的全长序列已递交GenBank,并被世界卫生组织HLA因子命名委员会正式命名为C*0121.结论 本研究发现了1个罕见的中国汉族人群HLA-C基因座位上的基因重组家系,阐明了HLA-C*0121新等位基因及单倍型的产生来源,为更深入研究基因重组及HLA多态性形成机制提供了理论依据.

Abstract：

Objective To study the inter-allelic recombination event occurring in the HLA-C locus in a family of Chinese Han nationality, and to evaluate the molecular genetic background of the new HLA allele.Methods Peripheral blood samples were collected from a Chinese leukemia woman patient, as well as her healthy parents and two brothers.HLA-A, C, B, DRB1 and DQB1 alleles were typed by high-resolution PCR-sequence-based typing (SBT) method using Atria Genetic AlleleSEQR HLA SBT kits.The Protrans S4 HLA-C single allele-specific sequencing strategy was used to separate the two HLA-C alleles and to determine novelty of the allele.The full length sequences of HLA-C alleles of the patient and her parents were further analyzed using cloning and haplotype sequencing method. The HLA five loci linked haplotypes and the recombination site were analyzed by family study, meanwhile the full length sequences of the five HLA-C alleles were compared with the IMGT/HLA database by the program "BLAST".Results The two haplotypes of the father and mother were a:A*0207-C*010201-B*550201-DRB1*090102-DRQ1*030302 and b:A*240201-C*120202-B*5201-DRB1*1502-DRQ1*0601, c:A*300101-C*060201-B*130201-DRB1*0405-DRQ1*0401 and d:A*110101-C*070201-B*4001-DRB1*080302-DRQ1*0601,respectively.The two brothers inherited their parent′s haplotypes a, d and b, c respectively.The two haplotypes of the patient were the maternal c and paternal recombinant a/b haplotype.The recombinant a/b haplotype A*240201-C*new-B*550201-DRB1*090102-DRQ1*030302, A*240201 came from the paternal haplotype b,while B*550201-DRB1*090102-DRQ1*030302 came from the other paternal haplotype a.When comparing the full length sequences of the HLA-C new allele with the father′s allele C*010201 and C*120202, it could deduce that the recombinant a/b haplotype derived from a recombination event occurring between the paternal chromosome 6 during meiosis.The crossover site was between genomic nt273 and nt330 of HLA-C alleles, which created a HLA-C new allele and the fifth haplotype of the family, and inherited it to the patient.The full length sequences of the new allele had been submitted to Genbank, and officially named C*0121 by WHO nomenclature committee.Conclusion This study demonstrates a rare inter-allelic recombination event occurring in the HLA-C locus within a Chinese Han family and illustrates the process of novel allele and haplotype, and provides direct theory for further studying the mechanisms of gene recombination and HLA polymorphism.     

反向PCR—SSOP技术行HLA—AB分型与临床应用

建立快速,准确的DNA分型技术并用于临床移植前HLA-AB配型,以弥补血清学分型技术的局限性。采用反向聚合酶链反应-序列特异寡核苷酸探针杂交技术（反向PCR-SSOP）进行DNA分型,可检出HLA-A（*0101-8001）和B（*07021-8201）等等位基因。结果表明,发现利用反向PCR-SSOP技术对所有样本分型均获成功,无假阳性和假阴性结果出现;美国洛杉矶加州大学（UCLA）质控细胞DNA分型结果与UCLA公布的测序结果一致。血清学与基因分型相比。血甭学结果HLA-A错检率6.4%和HLA-B错检率为7.4%。2例白血病病人分别有一个HLA抗原血清学方法不能检出。结论提示,反向PCR-SSOP技术用于HLA分型分辨率高,简单快速。结果直观、准确。分型结果较血清学方法更加精确,可适用于临床应用。     

广东汉族人群HLA-B~* 15等位基因分布

目的了解广东献血者汉族人群HLA-B*15等位基因的多态性。方法从1 691名广东汉族献血者中采用中/低分辨分型获得带有HLA-B*15基因型466例样本,进一步应用PCR-SBT技术进行测序分型,获得广东汉族人群B*15高分辨分型结果。应用PyPop软件计算HLA-B*15各等位基因频率,同时与其他人群资料进行比较。结果共检测到16种已知HLA-B*15等位基因,其中以B*15∶02(64.75%)最常见,其次为B*15∶01(13.26%),B*15∶25(4.554%),B*15∶27(4.158%),B*15∶12(3.960%),这5种等位基因占B*15等位基因家族的90.69%。在B*15等位基因家族中,表达B75抗原的等位基因B*15∶02、B*15∶11和B*15∶21共占67.92%,但表达B62抗原的B*15等位基因多态性最强,共检出6种等位基因。结论广东汉族人群中HLA-B*15等位基因表现出高度的多态性及其特有的分布特征。     

四川骨髓库汉族人群HLA-B~* 15等位基因分布

目的采用聚合酶链反应-序列分析基础上的HLA分型(polymerase chain reaction-sequence based typ-ing,PCR-SBT)方法,研究中国造血干细胞捐献者资料库(以下简称为中华骨髓库,CMDP)四川分库中四川籍汉族人群HLA-B*15组等位基因的分布特点。方法从四川骨髓分库中汉族人群中/低分辨分型HLA-B*15阳性样本中按不同血清学特异性分层抽取107例样本,应用PCR-SBT技术进行测序分型,获得四川籍汉族人群B*15组高分辨分型结果。应用方根法计算HLA-B*15各等位基因频率,同时与其他人群资料进行比较。结果共检测到16种已知HLA-B*15等位基因和1例未知等位基因。本研究中检出的16种等位基因有:B*15010101(B62),B*1502(B75),B*1503(B72),B*1505(B62),B*1507(B62),B*151101(B75),B*1512(B76),B*1513(B77),B*1517(B63),B*1518(B71),B*1525(B62),B*1527(B62),B*1529(B15),B*1532(B62),B*1546(B72),B*1558(B62)。其中以B*1502(36.2%)最常见,其次为B*15010101(21.6%),B*151101(9.5%),B*1518(6.9%),B*1525(6.0%),这5种等位基因占B*15等位基因家族的80%。在B*15等位基因家族中,表达B75抗原的等位基因B*1502和B*151101共占45.7%,但表达B62抗原的B*15等位基因多态性最强,共检出7种等位基因。此外,本研究发现1例未知等位基因,该等基因序列与目前所有已知的B*15或B*46等位基因序列均不相同,在外显子3的116位处存在1个点突变C->T。结论研究表明在四川籍汉族人群中HLA-B*15等位基因水平表现出丰富的多态性和特有的分布特征。     

中国北方汉族造血干细胞捐献者人类白细胞抗原-A、B、DRB1基因和单倍型高分辨水平的多态性研究

目的 从高分辨率水平研究中国北方汉族人群人类白细胞抗原(Human Leukocyte Antigens,HLA)-A、B、DRB1基因和单倍型的多态性.方法 采用聚合酶链反应-测序分型方法(Polymerase Chain Reaction-Sequence Based Typing,PCR-SBT)对631名随机北方汉族个体的HLA-A、B、DRB1基冈进行序列分析,进而采用最大似然性方法计算等位基因和单倍型的分布频率.结果 30个HLA-A等位基因中,频率高于0.05的5种常见等位基因A*1101、A*2402、A*0207、A*0201和A*3303的频率总和为69.26%;64个HLA-B等位基因中,频率高于0.05的4种常见等位基因B*4001、B*4601、B*5801和B*1502的频率总和为38.11%,41个DRB1等位基因中,频率高于0.05的7种常见等位基因DRB1*0901、DRB1*1501、DRB1*1202、DRB1*0701、DRB1*0803、DRB1*1101和DRB1*0405的频率总和为59.98%.499条A-B、659条BDRB1和2 426条A-B-DRB1单倍型中,分别有38、39和31条单倍型频率高于0.005,其频率总和分别为59.82%、53.69%和32.38%,A*0207-B*4601、B*4601-DRB1*0901和A*0207-B*4601-DRB1*0901分别为其最主要单倍型.结论 中国北方汉族人群高分辨水平的HLA-A、B、DRB1等位基因和单倍型的多态性数据可作为人类学、法医学、移植配型和疾病相关性研究和应用的参考数据.     

双精子嵌合体致ABO血型正反定型不符1例简

目的 对1例正定型呈混合凝集的ABO正反定型不符样本进行鉴定.方法 采用微柱凝胶法进行ABO、RhD血型鉴定、直接抗球蛋白试验和不规则抗体筛查,PCR-SSP法进行ABO基因分型,并分析外周血染色体核型.结果 先证者ABO正定型为红细胞混合凝集,反定型检出抗-A1;母亲和父亲分别为O型和AB型.先证者ABO基因座位存在O1、A201和B三个等位基因,其中O1来自母亲,A201和B来自父亲.核型分析显示先证者血液中存在46,XX和46,XY两种细胞,而父母核型正常.结论 先证者为孤雌分裂产生的两个相同的卵子被两个精子受精后所产生的嵌合体.     

HLA新等位基因HLA-B~＊5145的确认

背景：作者在用美国onelamba试剂公司生产的HLA低分辨试剂进行分型实验时,将反应结果导入HLA数据分析软件,发现HLA-B位点反应格局异常,且阴性磁珠和阳性磁珠反应情况良好,但是分析软件并未给出相应结果,怀疑有新基因的可能。目的：发现和认定1个HLA新等位基因。方法：采集中华骨髓库造血干细胞捐献者血样,应用PCR-SSO基因分型技术筛选可能的新等位基因,PCR产物测序和DNA基因克隆测序,分析基因序列。结果与结论：PCR-SSO基因分型显示,供者HLA-A位点基因型为A＊02XX,A＊33XX;HLA-DRB1位点基因型为DRB1＊1202,DRB1＊1302,HLA-B位点反应格局异常,不能指定任何HLA-B位点的等位基因,提示B＊44XX,B＊53XX;90FN,91FP,调整不合理,故进一步用其他试剂（Dynal,PCR-SSO）分型方法进行分析,也显示无法判定的结果。等位基因HLA-B＊5145是HLA-B＊5106的变异体,该基因和B＊5106的差异在第3外显子的339位碱基A→G,引起相应编码氨基酸113位上的N（天冬酰胺,Asn）→D（天冬氨酸,Asp）,346位碱基A→C,引起相应编码氨基酸115位上的Y（酪氨酸,Tyr）→S（丝氨酸,Ser）,362位碱基A→G,则不引起相应编码氨基酸120位上的K（赖氨酸,Lys）的变化。该基因为新等位基因,2006-10被世界卫生组织HLA因子命名委员会正式命名HLA-B＊5145。     

HLA-B新等位基因B*3936的确认和测序分析

本研究确认HLA新等位基因HLA—B％3936并分析其序列。先证者为脐血造血干细胞捐献者，样本DNA抽提采用PEL—FREEZ抽提试剂盒，利用单链特异性引物PCR方法扩增先证者HLA—B基因的第2—4外显子，对PCR产物直接进行第2、3、4外显子双向测序分析。结果显示：先证者样本中存在2个HLA—B等位基因，其中1个等位基因为HLA—B％4002，另1个经Blast验证确定为新的等位基因，新的等位基因序列已递交GenBank（DQ242650，DQ24265l，DQ242652）。与最接近的B％3901等位基因比较，新的等位基因在第3外显子上有4个核苷酸的差异，其中第527位T→A、第538位C→T、第539位T→G、第544位A→G，这引起氨基酸第152位缬氨酸（Val）→谷氨酸（Glu）、第156位异壳氨酸（Ile）→色氨酸（Trp）、第158位苏氨酸（Thr）→丙氨酸（Ala）。实验结果提示该等位基因为新的HLA-B等位基因，已被世界卫生组织HLA因子命名委员会正式命名为HLA—B％3936。     

4082名上海骨髓库汉族无关供者HLA-A、B、DRB1高分辨等位基因及单体型多态性研究

目的 了解上海地区汉族人群HLA-A、B、DRB1在高分辨分型水平上的等位基因及单体型频率分布特征.方法 采用PCR-测序分型技术(Sequence-based typing,SBT)对4 082名随机、无血缘关系、健康的中华骨髓库上海分库汉族造血干细胞捐献者进行HLA-A、B、DRB1高分辨基因分型,利用计数法和最大似然性原理方法分别计算HLA-A、B 、DRB1等位基因及单体型频率.结果 4082例样本中,共观察到204个HL4等位基因,其中频率＞0.1的HLA-A、B、DRB1等位基因分别有A*11:01、A*24:02、A*02:01、B*46:01、DRB1* 09:01、DRB1* 15:01.841条A-B单体型中,70条单体型呈现显著的连锁不平衡(ALD ＞0,HF≥3.67 ×10-4,x2 ＞3.84),8条表现为强连锁不平衡(RLD ＞0.40),17条单体型的频率高于0.01;1 027条B-DRB1单体型中,99条单体型呈现显著的连锁不平衡(ALD＞0,HF≥3.67×10-4,x2＞3.84),12条表现为强连锁不平衡(RLD＞0.40),12条单体型的频率高于0.01;3 344条A-B-DRB1单体型中,681条单体型是“可靠的”(频率≥3.67×10-4),单体型频率高于0.001有135条.结论 获得上海地区汉族人群HLA-A 、B、DRB1高分辨等位基因频率和单体型分布数据及相关遗传参数,为临床移植供者的选择、中国人群CWD表的制订、骨髓库最适库容的评估及人类遗传学研究提供参考数据.     

云南地区肾移植受者BK 病毒感染与HLA 等位基因相关性分析

目的　研究云南地区肾移植受者BK 病毒（BK virus，BKV）感染与人类白细胞抗原（human leukocyteantigen，HLA）等位基因HLA-B,HLA-DR 抗原分布频率，探讨肾移植受者BKV 感染与HLA-B，HLA-DR 抗原之间的相关性。方法　选取昆明市第一人民医院自2017 年6 月～ 2020 年12 月肾移植受者399 例为研究对象，按照BKV感染与否分为BKV 感染组(n=126) 和BKV 未感染组(n=273)。应用聚合酶链反应序列特异性引物技术（polymerasechain reaction sequence specific primer，PCR-SSP）检测HLA-B 和HLA-DR 等位基因，用SPSS 软件分析肾移植受者BKV 感染尿液阳性HLA-B 和HLA-DR 抗原分布频率，比较HLA-B 和HLA-DR 抗原与BKV 感染不同结局的关系。结果　BKV 未感染组检出的HLA-B 等位基因有33 种，占比大于10% 的基因型有7 种，分别为 HLA-B*13（16.85%），HLA-B*46（19.41%），HLA-B*51（10.62%），HLA-B*55（10.62%），HLA-B*60（17.58%），HLA-B*62（24.91%）和HLA-B*75（16.48%）；BKV 感染组中检出的 HLA-B 等位基因有25 种，其中占比大于10% 的基因型有5 种，分别为HLA-B*46（24.60%），HLA-B*55（10.32%），HLA-B*60（24.60%），HLA-B*62（22.22%）和HLA-B*75（15.87%）。BKV 未感染组检出的HLA-DR 等位基因有14 种，其中占比大于10% 的基因型有7 种，分别为 HLA-DR*4（30.40%），HLA-DR*8（15.75%），HLA-DR*9（20.15%）， HLA-DR*11（12.45%），HLA-DR*12（42.12%）, HLA-DR*14（20.15%）和HLA-DR*15（25.27%）；BKV 感染组中检出的 HLA-DR 等位基因有14 种，其中占比大于5% 的基因型有8 种，分别为 HLA-DR*4（27.78%）， HLA-DR*8（18.25%）， HLA-DR*9（16.67%）， HLA-DR*11（11.11%），HLA-DR*12（42.86%），HLA-DR*13（11.90%），HLA-DR*14（23.81%）和HLA-DR*15（19.84%）。HLA-B*13 等位基因在BKV 未感染组检出率高于BKV感染组（χ2=4.642，P=0.031）；HLA-DR*17 等位基因在BKV感染组的检出率高于BKV未感染组（χ2=4.791，P=0.029）。结论　云南地区肾移植受者 HLA-B*13 等位基因可能是抗BKV 的保护因子；而HLA-DR*17 等位基因可能与BKV 感染的机会呈正相关。     

HLA测序技术在非亲缘性脐血移植应用价值探讨

1998年6月至2004年7月，广州脐血库向国内21家移植中心54例患者提供了非亲缘性异基因脐血。为了探讨非亲缘性脐血移植供／受者HLA等位基因及其亚型与脐血移植GVHD发生率的关系，对54例非亲缘性脐血移植病例中，半年后有反馈随访资料的48例，利用盐析或柱提法提取移植的非亲缘性脐血的DNA及移植病例的全血DNA，采用HLA—SBT方法分别对HLA—A、B、DRB1位点进行了高分辨分型，并与我库脐血收集常规采用的HLA—SSP（HLA—Sequencing specific primers）低分辨结果进行了比较分析。结果发现，HLA不合位点不多于2个和HLA不合位点不少于3个的病例GVHD的发生率具有统计学显著性差异（P〈0．05）。在对HLA—A、B、DRB1等位基因高分辨单因素分型结果中，HLA—B和HLA-DRB1等位基因匹配全相合的病例GVHD发生率显著低于不完全相合病例GVHD的发生率（P=0．000，P=0．005）。结论：PCR—SBT技术在非亲缘性脐血移植HLA配型方面具有重要的临床应用价值。     

新的HLA-B*4061等位基因的核苷酸序列分析

本研究探讨HLA新的等位基因HLA-B＊4061的分子基础。采用盐析法抽提样本DNA，利用PCR方法扩增先证者HLA-B基因的第1-8外显子，PCR产物直接经TOPO克隆到质粒载体中得到单链，对所得克隆进行HLA-B基因第2、3、4外显子双向测序分析。应用PCR-SSP方法证实测序所发现的突变。结果表明：先证者样本克隆测序得到2个等位基因，其中1个等位基因为B＋4601，另1个经blast验证其为新的等位基因，新的等位基因序列已递交GenBank（DQ089628，DQ089629，DQ089630）。与最接近的B＊400101等位基因序列相比，新的等位基因仅在第2外显子上有1个核苷酸不同，即第272位C→A，导致第67位氨基酸Ser→Tyr。结论：HLA-B＊4061等位基因为新的HLA-B等位基因，已荣获世界卫生组织HLA因子命名委员会正式命名。     

Incidence of abacavir hypersensitivity and its relationship with HLA-B*5701 in HIV-infected patients in Taiwan

OBJECTIVES: To describe the incidence of hypersensitivity to abacavir and frequency of human leucocyte antigen (HLA)-B*5701 in HIV-infected Taiwanese persons. METHODS: Medical records of 337 HIV-infected Taiwanese in whom abacavir-containing combination antiretroviral therapy (CART) was prescribed from 1 May 2001 to 31 December 2006 were reviewed, and HLA typing of the patients was performed in 320 patients (232 receiving abacavir and 88 not receiving abacavir) with available blood samples. HLA class I and II polymorphisms were determined by PCR with specific primers. HLA-B*5701 was further confirmed by sequence-based typing. RESULTS: Of the 337 patients, median CD4 count was 166.5 cells/mm3 (range, 1.0-1914.0) and 83 patients (24.6%) had AIDS-defining opportunistic infections. Thirty-eight patients (11.3%) discontinued abacavir within 6 weeks of starting abacavir-containing CART. Among them, 10 patients had successful abacavir re-challenge and another 11 patients had other specific reasons for abacavir discontinuation. Therefore, 14 patients (4.2%) were classified as cases in whom abacavir hypersensitivity could not be excluded, and 3 patients (0.9%) met the criteria of abacavir hypersensitivity. Of the 320 patients undergoing HLA typing, HLA-A02 was the most common allele and only one individual (0.3%) expressed HLA-B*5701. Along with some differences in allele distributions, there was a significant difference in the genetic frequency of HLA-B57 in our patients compared with those of previous studies in other Chinese populations. CONCLUSIONS: Abacavir hypersensitivity was less frequently encountered in HIV-infected Taiwanese initiating abacavir-containing CART than in Caucasians, which might be explained by the low frequency of the HLA-B*5701 allele.     

6965名汉族骨髓供者HLA多态性分析

目的　分析中国汉族骨髓供者的人类白细胞抗原 (HLA)多态性 ,并寻找和鉴定新的HLA等位基因。方法　采用序列特异性引物聚合酶链反应、DNA测序技术以及分子克隆等以DNA为基础的HLA基因分型技术。结果　共鉴定 6 96 5人份无关汉族骨髓供者的HLA A、B、DRB1座位上的等位基因 ,其中 4 70 7人份为南方汉族个体 ,2 2 5 8人份为北方汉族个体。在受检群体中共检出 72种HLA特异性 ,包括过去很少在汉族人群中被检测到的HLA A2 5、A34、A74、B4 1、B4 2、B5 3、B73、B81等。HLA A、B、DRB1座位上尚未被检测出的空白基因频率分别小于 0 .2 0 % ,0 .2 5 %和 0 .70 %。发现 3个新等位基因 ,已被WHO命名为HLA A 0 2 5 3N ,HLA A 1114和HLA B 5 6 10。结论　在骨髓供者HLA分型中使用以DNA为基础的基因分型技术 ,可以得到精确可靠的基因频率以及发现新的等位基因。一些HLA基因在南北汉族人群中的分布有明显的差异 ,为了能最大限度地募集到带有不同HLA分型的骨髓供者 ,有必要在我国南北多个地区筛选骨髓供者