ABO血型系统中Aw基因分子遗传背景的研究与分析

目的：研究一个含有Aw亚型中国汉族家系的ABO基因的遗传机制。方法：对1例血型血清学鉴定为Aw亚型的样本及有关家系，采用PCR-SSP扩增、DNA测序方法，以A101-致序列进行比对，对其ABO等位基因的第6外显子、第6内含子及第7外显子进行基因克隆和单倍体测序分析。结果：血清学为Aw型样本中ABO基因序列与ABO*A101相比有两个位点发生了突变(467C&;gt;T，543G&;gt;T)，文献中未见报道，为一个新的A等位基因，该样本的家系5人中，2人带有这个新变异的A等位基因。结论：543位突变倒致编码ABO糖基转移酶的156位氨基酸由脯氨酸(Pro)变为亮氨酸(Leu)，大大降低了酶活性；这个位点对转移酶的活性是至关重要的。     

复合型ABO糖基转移酶的分子生物学与酶动力学的研究

在输血医学最基本的AB0血型系统中，存在着为数不少的ABO抗原性减弱的表型。现在已对这些ABO血型弱表达现象的分子基础进行了广泛的研究，从基因和糖基转移酶水平阐明了部分亚型的调控机理。ABO血型中最为特殊是Cis—AB和B（A）。现已知道2者在基因上可以用相同的理论来解释，随着当前临床使用的商品化血型单克隆抗血清的普及，回顾以前的血清学案例，我们可以把这2个血型放在一起研究。Cis-AB和B（A）血型均具有双重复合糖基转移的功能。     

ABO血型基因研究进展

自1900年人类红细胞ABO血型被发现后的105年中,已至少检测出29个血型系统、240种以上的血型抗原。ABO是临床上最为重要的血型系统,它的应用已从临床输血扩展至生物学、遗传学、法医学和人类学等许多方面。血型研究百年历史大致可分为3个阶段:从1900年到上一世纪1950年代,使用血     

ABO血型变异与B糖基转移酶关系研究

目的研究ABO血型B亚型系统Bw亚型与B糖基转移酶的关系。方法运用血型血清学鉴定方法鉴定1个家庭2例ABO血型的Bw亚型,运用聚合酶链式反应的方法扩增糖基转移酶1~7号外显子,送到试剂公司测序。结果直接测序发现2例ABO血型的Bw亚型,其中B糖基转移酶基因第721位C〉T的转变,导致糖基转移酶多肽链Arg241Trp的转变。结论糖基转移酶基因第721位的C〉T的突变引起糖基转移酶活性的消失或者减弱,导致Bw亚型。     

Am新等位基因分子遗传背景的研究

目的鉴定ABO新等位基因,分析Am亚型的分子基础。方法对1例血清学鉴定为Am亚型的标本,PCR扩增ABO等位基因的第6、7外显子及侧翼内含子,PCR产物采用直接测序和克隆测序的方法,确定其基因型。结果在血清学鉴定为Am亚型的标本中发现一个突变的A等位基因,它与ABO*A105等位基因相比只有1个点突变(595C>T)。结论 595位突变导致编码A糖基转移酶的199位氨基酸由精氨酸(Arg)转变为半胱氨酸(Cys),极大降低了酶的活性,表明199位氨基酸对决定ABO糖基转移酶活性是十分关键的。     

ABO血型基因转录调控机制中微卫星序列的研究

目的研究与AB0血型基因转录机制中CBF／NF—Y调控因子黏附的AB0基因5’端微卫星序列。方法收集且筛选出已经AB0表达编码序列测定的AB0基因型血液DNA标本共计21例，其中包括A101／A101基因型的标本2个，A102／A102基因型的标本5个，B101／B101基因型的标本5个，001／001型3例，002／002型6例，设计引物，PCR扩增AB0基因5’端-nt3949至-nt3612住，产物经胶回收后，使用同样的引物进行直接序列测定。结果A101和A102等住基因在CBF／NF—Y黏附区域的微卫星序列只有一个43碱基长度的重复，B101，001，002等住基因在此区域是四个43个碱基长度的重复；且A101等住基因的这个43碱基的第nt41住为A，而B101等住基因的4个重复序列中nt41均为G，001和002的第1个重复中nt41为C，另外3个重复序列的nt41为G。结论转录调控因子黏附的ABO血型基因的微卫星增强子序列根据AB0基因的不同呈现变异，所有常见的AB0等住基因在此区域呈现多态性。     

中国人群ABO血型系统基因分型研究与应用

背景:ABO血型是输血医学中最重要的血型系统,血型血清学定型技术具有简单实用的特点已广泛应用于ABO血型中的鉴定中,但是血清学试验存在局限性,而基因技术在某种程度上克服了血清学试验的缺点.目的:研究中国人群ABO基因多态性,并将基因分型技术用于解决临床输注中血型血清学难题.设计:随机选取样品,与常规血型血清学结果相比较,分析基因型结果.单位:一所市级血液中心输血医学研究所.对象:选择2002-03/2002-12在深圳市血液中心参加捐血的无血缘关系的中国汉族无偿献血个体260人为研究对象,其中男110人,女150人,年龄18～50岁.1例血清学技术正反定型不符的标本来自本血液中心并调查其家系,6例血清学疑为A2型的标本来自第二人民医院等4个本市医院输血科.方法:快速盐析法提取外周血中的DNA,采用聚合酶链反应-序列特异性引物基因方法对ABO血型定型,并且在吸收放散试验、唾液血型物质凝集抑制等血清学试验基础上,用聚合酶链反应-序列特异性引物法扩增ABO血型的等位基因.主要观察指标:260人份样品ABO血型系统的基因型及疑难血型样品的血清型与基因型.结果:在中国汉族符合Hardy-Weinberg平衡的随机群体(260人)中,检出O1,B,A1O1(A467C)和A1O2/1O3(A467T)4种等位基因,其基因频率分别为0.582 7,0.184 6,0.009 6,0.223 1.在疑难血型鉴定中6份血清学定为A2的标本中,只有2例基因分型确定为A2O1O1,其余均为A1O2/A1O3O1型,在一家系疑难血型鉴定中,兄弟3人均为类孟买型,ABO基因分型分别为A1O2B,A1O2B,A1O2O1.结论:ABO聚合酶链反应-序列特异性引物基因分型是一种方便、快速、可靠的技术,可以弥补血型血清学鉴定方法的不足.     

异常ABO表型遗传的分子背景研究

ABO系统是人类最早发现的血型系统,其血清学分型简便、稳定.1925年Bernstein确定ABO血型遗传学说之后,开始被应用于法医学上真正科学意义的亲权关系鉴定.ABO血型的遗传符合经典的遗传规律,直到1964年cis-AB血型的发现,人们才开始进一步研究血型的遗传规律.到目前为止,国内外陆续报道了数个罕见家系,在DNA多态性分析结果显示不能排除或肯定其亲权关系的家族成员中,ABO血型表型遗传不符合孟德尔遗传规律,这引起了研究者对经典遗传规律的质疑.经过血型工作者对ABO血型的分子遗传背景深入研究,已能从ABO基因水平解释此异常现象.     

ABO血型系统B101-O02等位基因杂交导致的Bw亚型

目的 研究中国汉族个体红细胞ABO血型Bw亚型的分子遗传背景.方法 通过标准血型血清学方法 鉴定了1个家庭3例ABw亚型,PCR扩增样本基因组DNA的ABO基因增强子、启动子和外显子1～7及侧翼内含子序列,PCR产物经割胶纯化后直接测序,并将含有多态性位点的外显子7克隆到pcDNA3.1(-)质粒,转化DH5α后进行单倍体序列分析.结果 3例ABw亚型的直接序列分析发现其ABO基因均有A102、B101和002等3种等位基因部分序列特征,但无法直接确定其基因型.单倍体序列分析表明,其中1个等位基因为A102,另1个为B101-O02杂交等位基因,表现为B101等位基因基础上的646T>A,657T>C和681G>A变异.在110份随机样本中未发现该杂交等位基因.结论 B101和O02等位基因杂交可能是导致该Bw亚型的分子机制.     

ABO血型系统的基因分型

本文介绍了ＡＢＯ血型系统的分子基础及在此基础上对ＡＢＯ血型系统的基因分型的几种主要方法：ＰＣＲ－ＤＮＡ测序法、ＰＣＲ－限制性内切酶酶切法、ＰＣＲ－限制性片段长度多态性（ＲＦＬＰ）、ＰＣＲ－序列特异性引物（ＳＳＰ）、ＰＣＲ－单链构象多态性（ＳＳＣＰ）等。另外还介绍了基因分型技术在ＡＢＯ亚型研究中的应用。     

Nondeletional ABO*O alleles express weak blood group A phenotypes

BACKGROUND: Owing to a single-base deletion, the vast majority of ABO*O alleles encode for a truncated and catalytically inactive ABO glycosyltransferase, leading to the generation of a premature stop codon. Less frequent nondeletional ABO*O alleles such as ABO*O03, in contrast, have nonsynonymous mutations that may abolish the protein's enzyme activity by altering its sugar-binding site. STUDY DESIGN AND METHODS: Extensive ABO phenotyping and genotyping were performed in healthy blood group O donors with weak anti-A isoagglutinins and their relatives as well as in blood group O donors selected for the presence of ABO*O03. HeLa cells were used to transfect ABO expression plasmids. RESULTS: Donors or relatives carrying ABO*O03 and/or its rare variant ABO*Aw08 in homozygous (n = 2) or heterozygous (n = 14) form showed weak A antigen expression detectable only by adsorption-elution (n = 15) or by monoclonal anti-A typing (n = 1). The serum samples of most donors (n = 13) contained weak anti-A; in the remaining donors, anti-A isoagglutinin reactivity was in the normal range. In the transfection studies, weak A antigen expression on HeLa cells transfected with plasmids containing ABO*O03 or ABO*Aw08 expression constructs was detectable only by adsorption-elution. CONCLUSION: The data provide evidence that nondeletional ABO*O03-like alleles produce detectable amounts of A antigens.     

Evolution of the O alleles of the human ABO blood group gene

BACKGROUND: To date, at least 40 different alleles O have been characterized on the basis of exon 6 and exon 7 sequences but not always for intron 6. STUDY DESIGN AND METHODS: Among 415 individuals, from four continents (Africa, Europe, South America, and Asia), studied for exon 6 and exon 7 sequences, we selected 46 individuals (of respective phenotypes O [39], AB [3], B [3], or A [1]) for sequencing 1800-bp amplicons spanning exon 6, intron 6, and exon 7. The amplicons were characterized either by direct sequencing or after cloning when required. RESULTS: We defined 14 new intron 6 O allele sequences, including four recombinant alleles. Based on sequence comparison, a phylogenetic network was constructed. It confirmed recombinant allele origins and that most O alleles are derived by point mutations from the two worldwide distributed alleles O01 and O02. CONCLUSION: Allele O phylogenetic analysis suggests that the most frequent silencing mutation (deletion of a G in exon 6) appeared once in human evolution in the ancient O02 allele lineage and that allele O01 resulted from an interallele exchange between O02 and A101. Assuming constancy of evolutionary rate, diversification of the representative alleles of the three human ABO lineages (A101, B101, and O02) was estimated at 4.5 to 6 million years ago.     

ABO blood group in Kuwaitis: detailed allele frequency distribution and identification of novel alleles

BACKGROUND: The ABO blood group is clinically the most important blood group system and can now be genotyped easily by DNA-based methods without family studies. STUDY DESIGN AND METHODS: Samples (n = 166) from a Kuwaiti population were phenotyped by standard serologic techniques for the ABO blood group and genotyped for the ABO locus by an established multiplex polymerase chain reaction protocol followed by single-strand conformation polymorphism (SSCP) analysis. Nonstandard SSCP patterns were investigated by DNA sequencing of exons 6 and 7 and, if necessary intron 6. RESULTS: Standard SSCP patterns identified six classical alleles in this population: A101 (0.1115), A102 (0.0181), A201 (0.0301), B101 (0.1627), O101 (0.3103), and O201 (0.2500). One A, 1 B, and 8 O variant alleles were identified (total frequency, 0.1175). All variant alleles were each present in one or two chromosomes (< or =0.0060) in our samples except O109 (0.0813). Three of these 10 variant alleles were novel alleles defined by newly identified single-nucleotide polymorphisms in exon 7 (527G>A, 687C>T, and 1116G>A). One new base substitution result in amino acid change. CONCLUSIONS: This is the first study reporting the detailed distribution of ABO alleles and genotypes in Kuwaitis. Sixteen alleles were identified, including 3 novel alleles.     

Ael亚型的分子生物学研究

目的　研究汉族ABO血型系统Ael亚型分子基因基础。方法　在标准血清学鉴定的基础上 ,对 2例汉族Ael亚型进行PCR SSP基因分型。并根据第 6、7外显子及两侧内含子的保守序列设计引物进行扩增 ,PCR产物经割胶纯化后直接序列分析。结果　PCR SSP基因分型排除了其中一个等位基因为A2 、B、O1和O2 基因的可能。DNA序列分析表明 ,该Ael亚型基因与A1基因相比 ,有 (798～ 80 4 )G插入和C(I 5 / 5 32 )T两处突变 ,推测的蛋白质除羧基端 86个氨基酸残基与A1糖基转移酶不同外 ,还比A1转移酶多 37个残基。结论 (798～ 80 4 )G插入和C(I 5 / 5 32 )T两处突变揭示了Ael亚型的分子基础     

New and unusual O alleles at the ABO locus are implicated in unexpected blood group phenotypes

BACKGROUND: In the ABO blood group system mutations in the A gene may lead to weak A subgroups owing to a dysfunctional 3-alpha-N-acetylgalactosaminyltransferase. STUDY DESIGN AND METHODS: Blood and DNA were investigated to correlate weak A phenotypes with genotype, and an overrepresentation of the infrequent O2 allele was observed. Consequently, 57 available O2 alleles were examined in detail. RESULTS: Two new O2 alleles were identified having mutations resulting in Gly229Asp with or without Arg217Cys. A recently described O2 variant (488C>T; Thr163Met) was also found. Surprisingly, both the original and the variant O2 alleles were associated with either O or Aweak phenotypes. Three novel O alleles surfaced in six other samples with suspected A subgroups. These were A1-like alleles having nonsense mutations causing premature truncation at codons 56, 107, or 181. A second example of the rare O3 allele was also identified. A newly described O1 allele having 768C>A was found to be the third most frequent O allele among Swedish donors. Of the five novel O alleles, three were incorrectly interpreted as A1 following routine ABO genotyping. CONCLUSION: Apparent O alleles lacking 261delG may cause weak A expression on red blood cells and/or inhibit anti-A production. A hypothesis that exchange of genetic material between principally dissimilar O alleles during mitosis ("autologous chimerism") restores glycosyltransferase activity in some cells would explain this interesting phenomenon.     

1例罕见AB3亚型的分子机制

目的探讨1例罕见AB3亚型的分子机制。方法对1例ABO血型正反定型不符患者的血型通过血清学鉴定、PCR-SSP、ABO基因直接测序、TA克隆单体型分析等方法分析其分子机制。结果该患者血型鉴定为比较少见的A102/B301亚型,该亚型是由于ABO基因第七外显子存在1054C/T杂合导致R352W氨基酸改变所致。结论 ABO基因存在1054CT,该突变可能是导致B301亚型的分子遗传基础之一。关健词:     

献血者ABO血型正反定型不符检测结果分析

目的分析献血者ABO血型正反定型不符的情况,采用分子生物学技术准确鉴定血型,为安全输血提供保障。方法收集2016年6月至2017年6月本血站73例ABO血型正反定型不符标本,采用血型血清学方法检测ABO血型,PCR-SSP法及直接测序方法确定基因型。结果 73例正反定型不符标本中ABO血型正定型为A型,抗-B减弱标本56例,检出4种基因型分别为19例AO1、21例AO2、15例AA、1例A205O2为A2亚型;正定型为B型,抗-A减弱9例,检出2种基因型分别7例BO1、2例BO2;正定型为O型,抗-B减弱7例,检出3种基因型分别为2例BO1为B亚型、4例O1O2、1例O1O1;正定型为O型,抗-A减弱1例,检出基因型AO1为A亚型。其中,4例ABO亚型经基因测序结果分别为A205/O02、Bel03/O01、Bw17/O01、Ax01/O01。结论对于献血者正反定型不符时,应通过血清学与基因检测及DNA测序相结合的方法,正确鉴定血型,为临床提供安全的血液。     

ABO blood group antigens of human spermatozoa

ABO blood group antigens on the membrane of human spermatozoa were investigated with the peroxidase-labelled antibody test. Spermatozoa from O secretor were incubated with saliva or seminal plasma of A and B secretors, but the specific peroxidase staining was negative. This result indicates that blood group antigens on human spermatozoa originate from spermatozoon itself, but not from seminal plasma.     

8860名学生ABO血型分布及批量检测ABO血型错检原因分析

[目的]了解学生群体中的ABO血型分布情况,有利于临床医务人员及相关工作人员掌握血源概况,为血液血型贮备对策提供科学依据,并分析造成批量ABO血型错检的原因。[方法]运用玻片凝集法和试管离心法对8860名学生进行ABO血型鉴定,对可疑血液样本做盐水试管法的正反定型试验。[结果]血型分布为A型占27．75％,B型占31．65％,O型占29．65％,AB型占10．95％。[结论]8860名学生血型分布为B〉O〉A〉AB。当发现血型鉴定出现可疑时,首先应重复做试验一次,严格执行操作规程,细心观察结果,按步骤一步步排除错检的可能性。