广东汉族人群补体C2 , Bf, C4的遗传多态现象

对110例广东汉族人血清作了补体C2, Bf, C4的测定,其基因频率分V1为：C2*C'0.9500, C2*B: 0.0227,C2-,4:0182, C2*QO:O．0091;Bf*S：0．8364, Bf^`F:0．1409, Bf*S07：0．0091, Bf *S025： 0.009i,Bf*S055：0,0045; C4*A3：0.6327,C4*A4：0．1327,C4*_00：0．1020, C4*A5：0．0255 （一4*A2: 0·0918,C4*,41：0．0053;C4*B1：0．4569, C4*B2：0．4416, C4*QO:O．0558,C4*B5：0．0152,C4"}B96： 0.0152, C4*B3:0.0102, C4*B92:0.0051。木调查在我国首次发现一例C2*QO纯合子。     

两种构祀植物花药培养单倍体的诱导

对110例广东汉族人血清作了补体C2, Bf, C4的测定,其基因频率分V1为：C2*C'0.9500, C2*B: 0.0227,C2-,4:0182, C2*QO:O．0091;Bf*S：0．8364, Bf^`F:0．1409, Bf*S07：0．0091, Bf *S025： 0.009i,Bf*S055：0,0045; C4*A3：0.6327,C4*A4：0．1327,C4*_00：0．1020, C4*A5：0．0255 （一4*A2: 0·0918,C4*,41：0．0053;C4*B1：0．4569, C4*B2：0．4416, C4*QO:O．0558,C4*B5：0．0152,C4"}B96： 0.0152, C4*B3:0.0102, C4*B92:0.0051。木调查在我国首次发现一例C2*QO纯合子。     

云南肺癌易感性与HLA-A，HLA-B，DRB1，DQB1等位基因频率的相关性研究

目的:测定云南肺癌患者人类白细胞抗原(human leukocyte antigen,HLA)-A、B、DRB1、DQB1等位基因出现频率,探讨HLA各等位基因位点与云南省肺癌发病易感性的相关性。方法:采用病例-对照相关分析方法,选取云南籍肺癌患者和健康个体各30例,应用序列特异性引物聚合酶链反应(polymerase chain reaction-sequence specific primer,PCR-SSP)对HLA-A、HLA-B、HLA-DRB1及HLA-DQB1等位基因频率进行测定,与正常组对比测算相对危险因子(relative risk,RR)。结果:肺癌组的HLA-A~*02频率为90.0%(A~*0201为主),B~*46频率为40.0%,DRB1~*15频率为40.0%,较对照组的43.30%、0%、10.0%明显升高(Pc0.05,RR1)。肺癌组的HLA-A~*31频率为3.30%,A~*33频率为6.70%,B~*27频率为3.30%,B~*52频率为6.70%,DRB1~*03频率为0%,DRB3~*01频率为60.0%,DQB1~*02频率为0%,DQB1~*06频率为0%,较对照组的23.30%、26.70%、26.70%、26.70%、23.30%、86.70%、23.30%、26.70%降低明显,(RR1,Pc0.05)。结论:云南肺癌易感性可能与HLA-A~*02的频率(90%)具有相关性;而HLA-A~*31、HLA-A~*33、HLA-B~*52、HLA-B~*27、HLA-DRB1-~*03、HLA-DRB3~*01、HLA-DQB1~*02及HLA-DQB1~*06在肺癌患者中的频率较低,在云南肺癌发病中可能具有遗传拮抗作用。     

湖南地区HBV患者MHC-Ⅰ类链相关基因A第五外显子微卫星多态性研究

分别提取湖南汉族人群108例慢性乙肝病毒(hepatitis B virus,HBV)患者、96例HBV携带者和142例健康对照者外周血基因组DNA,利用聚合酶链反应和基因扫描技术分别对它们的主要组织相容性复合体Ⅰ类链相关A(major histocompatibility complex class Ⅰ chain related A,MICA)基因第5外显子进行微卫星多态性分析;应用DNA测序分析对不同的基因型进行验证,同时应用PCR/SSP技术进行MICA*Del检测,确定MICA基因第5外显子基因型.发现本研究的三组中分别检出A4、A5、A5.1、A6、A9五种等位基因,且以A5和A5.1为主;在HBV携带组和健康对照组中分别检出MICA* Del基因.结果同时显示慢性HBV患者组MICA*A5.1/A9基因型频率、慢性HBV患者组的MICA*A9等位基因频率、慢性HBV患者组MICA* A9表型频率和HBV携带组MICA*A5.1/A9基因型频率均低于相应的健康对照组;而湖南地区汉族人群HBV携带者和慢性HBV患者间的基因型频率、等位基因频率和表型频率无显著性差异;因而推测MICA*A5.1/A9基因型和MICA*A9等位基因可能是抗HBV感染的一种保护性等位基因.为今后进一步研究HBV的感染、预防和治疗提供参考依据.     

中国3个地区汉族人群补体C6的遗传多态性研究

运用聚丙烯酰胺凝胶等电聚焦(PAGIF)和免疫吸引技术,研究了3个地区汉族人群的C6多态性。得到的基因频率如下:漳州市——C6*A:0.4634、C6*B:0.5000、C6*R:0.0366(C6*B2:0.0317);成都市——C6*A:0.4975,C6*B:0.4484,C6*R:0.0545(C6*B2:0.0395);哈尔滨市——C6*A:0.4708,C6*B:0.5219,C6*R:0.0073(C6*B2:0.0073)。蒙古人种的C6*A频率一般都低于0.5,高加索人种的C6*A频率一般都高于0.6。黑人则介于两者之间。蒙古人种与高加索人种的另一个区别在于前者的C6*B2频率在0.03到0.07之间,而后者几乎没有C6*B2。     

补体第六成分（C6）在汉族5个群体中的多态分布

用聚丙烯酰胺等电聚焦技术和免疫酶标法,调查分析了汉族5个群体补体第六成分(C6)的遗传多态性,得出基因频率如下。郑州汉族:C6*A 0.4521、C6*B 0.5228、C6*B_2 0.0183、和C6*R 0.0068。兰州汉族:C6*A 0.4612、C6*B 0.5218和C6*B_2 0.0170。呼和浩特汉族:C6*A 0.4452、C6*B 0.5286、C6*B_2 0.0214和C6*R 0.0048。西安汉族:C6*A 0.4899、C6*B 0.4874、C6*B_2 0.0126和C6*R 0.0101。广东梅州客家人:C6*A 0.4569、C6*B 0.5152和C6*B_2 0.0279。C6*R为罕见等位基因之频率。     

单体异附加系花药培养创制小麦- 中间偃麦草纯合易位系

利用单体异附加系花药培养细胞工程途径,诱导小麦与中间偃麦草发生染色体易位,通过细胞学分析、荧光原位杂交(F ISH)和SSR鉴定出纯合易位系.研究结果表明,经单体异附加系花药培养创制出1个小麦-中间偃麦草纯合易位系99-803;其花粉母细胞(PM C s)减数分裂中期I染色体构型为18.42个环状二价体 2.57个棒状二价体 0.01个单价体;中间偃麦草的7A i-1染色体与小麦7A或7B染色体发生了非罗伯逊易位,且中间偃麦草易位片段较小;通过该途径获得纯合易位系的频率约为2%.以上结果表明,单体异附加系花药培养是一条向小麦转移异源染色体小片段(基因)的快速高效途径.     

中国维、苗、瑶、壮四个少数民族补体C4的遗传多态现象的检测报告

使用国际第四届补体遗传学会议推荐的方法及薄层激光扫描技术,检测了我国维吾尔族、苗族、瑶族、壮族的补体组分4(C4)的多态性,并与我们以往检测过的汉族的C4多态性一起进行了比较。结果发现,在C4A座位上,以C4A3频率最高,以下在汉族、苗族、瑶族、壮族中依C4A2、Q0、4、1次序降低。在C4B座位上,频率最高的均为C4B1。其它基因频率的依次排列,汉与维为2、Q0、3,苗与壮为92、Q0、2、3,瑶为Q0、2、92等。民族间的差异比较集中地存在于C4A2、C4B2、C4AQ0、C4BQ0等4个基因。本文还对中国汉族、日本人、白种、黑种人群的C4同种异型差异进行了对比与讨论。     

内蒙古地区蒙古族HLA-A、B、DRB1基因座多态性分析

应用序列特异性寡核苷酸探针反向斑点杂交技术对内蒙古地区蒙古族106名无关健康个体的HLA-A、B和DRB1 基因座进行基因分型, 以研究内蒙古地区蒙古族人群HLA-A、B、DRB1基因座的等位基因及其组成的单倍型频率分布特征。 采用最大数学预期值算法计算HLA基因座的等位基因频率和单倍型频率。106 名内蒙古地区蒙古族个体的HLA-A、B、DRB1基因座分别检出13、29、13个等位基因。高频单倍型分别为 HLA-A*02-B*46 (0.0510); HLA-A*02-B*13(0.0495); HLA-A*02-B*51(0.0442); HLA-B*13-DRB1*07 (0.0555); HLA- B*46-DRB1*09(0.0378); HLA-B*35-DRB1*13(0.03300); HLA-A*02-B*13-DRB1*07(0.033019); HLA-A*02-B*46- DRB1*09(0.031985)。研究表明: 内蒙古地区蒙古族人群HLA基因座的等位基因和单倍型具有较高的遗传多态性。HLA- A*24-B*14, HLA-A*32-B*63在该民族具有极强的连锁不平衡。     

第25届国际生物学奥林匹克竞赛试题 理论A-4

正遗传与进化31.野生型果蝇分别和3种隐性纯合突变体:b(黑体)、sc(亮红眼)和vg(残翅)进行正交。所获得的F1代果蝇分别与对应的纯合突变体回交,所得F2代表型和比例如下表所示:请指出下面的描述正确与否。A.将2个F2代,仅体色为黑体,其他性状正常的果蝇杂交将获得不同的翅膀表型B.b和vg基因位点的相对距离小于20 cM C.b和sc为杂合,vg为纯合的果蝇将产生等比例的4种不同基因型的配子D.如果vg和sc杂合个体进行杂交,所得后代     

Polymorphism of the fourth component of complement in Turks

An analysis of polymorphism in the fourth component of human complement (C4) was performed on EDTA-plasma from 142 unrelated, randomly selected Turks without collagen-vascular disease or recurrent infections. Plasma samples treated with neuraminidase and carboxypeptidase-B were subjected to high-voltage agarose gel electrophoresis followed by immunofixation. C4B allotypes were further detected in some samples by Western blots with monoclonal antibody 1228 (anti-C4B/Ch1 reactivity). The frequencies of C4A and C4B alleles were determined. Allele C4B*5, which has been found to be relatively common in Asian (Oriental) populations, was not detected in this study. No specific predilection could be noted among the rare variants. C4A*3-C4B*1 was the most common haplotype (n = 40/142, or 28%) but was found less frequently than in Caucasian populations. This finding may be the result of the limited number of samples examined. C4A and/or C4B null allotypes were seen in 49 of 142 (34.6%) subjects. The most frequent C4 null allotype seen was C4B null (37/142, or 26%): 28 subjects had one C4B null allele; 1 had a homozygous deficiency of C4B (C4B*QO, *QO) and 7 had C4A*QO C4B*QO, a double heterozygous haplotype. Frequencies of homozygous haplotype C4A*Q0-C4B*Q0 in the population studied were found to be 0.007. The results of this study demonstrate that the genetic composition of the Turkish population exhibits both similarities and differences with the European population, and ranges between Caucasian and Mongoloid (Asian) populations.     

Genetic control of C6 polymorphism and C6 deficiency in rabbits

The genetic control of the sixth component of complement (C6) in rabbits has been studied by quantitation of C6 functional and antigenic levels and identification of polymorphism by isoelectric focusing (IEF) in gels. Patterns of inheritance of C6 variants in families carrying a silent gene for C6 were examined, and it was found that 3 common plasma phenotypic variants, C6 A, C6 B, and C6 QO were under the genetic control of allelic genes, C6*A, C6*B, and C6*QO. In IEF patterns, C6 A could be identified by its isoelectric point that was slightly more acidic than that of C6 B. C6 QO was undetectable because it lacked functional and antigenic activity. The C6*A/C6*B genotype displayed a mixed IEF pattern with bands characteristic of both C6 A and C6 B. Functional and antigenic levels of C6 that were found in heterozygous C6*A/C6*QO and C6*B/C6*QO rabbits were approximately one-half of the C6 levels found in the corresponding homozygous animals. The phenotypic variation closely resembles that previously observed in humans and rhesus monkeys, as well as preliminary data in rabbits. The patterns of inheritance indicated that the two common C6 structural genes and the deficiency gene were allelic variants at the same genetic locus.     

Deletion of complement C4 and steroid 21-hydroxylase genes in the HLA class III region

Molecular maps have been prepared of the HLA region on human chromosome 6 that includes the complement C4 and steroid 21-hydroxylase genes (21-OH), using DNA of individuals deficient (QO) in either of the two forms C4A or C4B. In all, 18 haplotypes with C4A QO were examined by Southern analysis and two had deletions of 28-30 kb that included both the C4A and 21-OHA genes. Of six C4B QO haplotypes, one had a deletion that included both the C4B and 21-OHA genes. Thus, some of the C4 null alleles are due to deletion of the gene but the majority in this sample are not. Deletion occurred in two common haplotypes suggesting that in the population as a whole, C4A deficiency is due to deletion in about one-half the C4A QO haplotypes. As duplication of C4A or C4B genes does occur, the possibility that unequal cross-over could explain the C4 deletion was examined by preparing cosmid clones from the DNA of an individual typed C4A QO. A cloned genomic fragment containing the single C4B gene was isolated and found to be similar to the homologous region of a cosmid from a normal individual carrying a C4A gene. This suggests that if a cross-over has occurred it is in a region where the two genes are identical. The biological significance of the rather frequent occurrence in the population of haplotypes with C4A or C4B deletion together with the accompanying deletion of the 21-OHA gene is discussed.     

Genetics of the quantitative Lp(a) lipoprotein trait

The Lp(a) lipoprotein is a complex particle composed of a low density lipoprotein (LDL)-like lipoprotein and the disulfide bonded Lp(a) glycoprotein. The complex represents a quantitative genetic trait. SDS gel electrophoresis under reducing conditions of sera followed by immunoblotting with affinity-purified polyclonal anti-Lp(a) demonstrated inter- and intra-individual size heterogeneity of the glycoprotein with apparent Mr in the range 400-700kDa. According to their relative mobilities compared to apo B-100 the Lp(a) patterns were categorized into phenotypes F, B, S1, S2, S3 und S4 and into the respective double-band phenotypes. This size heterogeneity seems to be controlled by multiple alleles designated LpF, LpB, LpS1, LpS2, LpS3, LpS4 and a null allele (LpO) at a single locus. Phenotype frequencies observed in 441 unrelated subjects were in good agreement with those expected from the genetic hypothesis. Comparison of Lp(a) lipoprotein concentrations in the different phenotypes revealed a highly significant association of phenotypes B, S1 and S2 with high, and phenotypes S3 und S4 with intermediate Lp(a) concentrations. A third mode is represented by the null phenotype were no Lp(a) band is detected upon immunoblotting and Lp(a) lipoprotein is low or absent. We conclude that the same gene locus is involved in determining Lp(a) glycoprotein phenotype and Lp(a) lipoprotein concentrations in plasma. This major gene seems to be the Lp(a) glycoprotein structural gene locus.     

Human MHC class III genes, Bf and C4. Polymorphism, complotypes and association with MHC class I genes in the Finnish population

Electrophoretically detected genetic polymorphism of human MHC class III genes, factor B (Bf) and complement C4A and C4B, was studied in the Finnish population. Bf alleles were determined in a panel of sera from 70 unrelated individuals. The common Bf alleles, Bf*S and Bf*F, had frequencies of 73% and 26%, respectively. Only in 1 individual was another allele, Bf*F1, detected. The frequencies of the C4A and C4B alleles were based on studies of 254 unrelated individuals. In this panel, five different alleles were detected at the C4A locus and four at the C4B locus. At both loci an allele without a gene product, i.e. a 'null' allele, was observed with high frequency, 11% for C4A 'null' and 17% for C4B 'null'. The association of complotypes to HLA haplotypes was analyzed in 70 chromosomes. The most common combination, defined by class I and class III alleles, was HLA-B7-S31 (13%), followed by HLA-B35-F20 (8.4%) and HLA-B8-S03 (7.1%). Some HLA-B specificities, for example B15, B27 and B40, were associated with a variety of complotypes. The importance of complotyping in HLA genetics is discussed.     

Restriction fragment analysis of duplication of the fourth component of complement (C4A)

The two genes encoding the fourth component of complement (C4A and C4B) reside between HLA-B and HLA-DR on human chromosome 6. Two kilobases downstream from each C4 gene lies a 21-hydroxylase gene (CA21HA and CA21HB, respectively). Utilizing the method of Southern blotting and a 5'-end 2.4-kb BamHI/KpnI fragment of the C4 cDNA, we have analyzed TaqI-digested DNA from four pedigrees with one or more extended haplotypes containing a C4A duplication, as demonstrated by protein electrophoresis and segregation analysis. Two C4A protein duplications (C4A*2,A*3,C4B*QO and C4A*3,A*5,C4B*QO) segregated with two large TaqI DNA restriction fragments (7.0 and 6.0). In pedigree Fi, one individual homozygous for HLA-A3,B35,C4,DR1,DQ1,BFF,C2C,-C4A2,3,C4BQO had TaqI 7.0- and 6.0-kb restriction fragments with equal hybridization intensities as measured by two-dimensional densitometry (7.0/6.0 kb = 0.83, SD = 0.12, N = 7). A hybridization probe for the 21-hydroxylase gene also demonstrated equal gene dosage (CA21HA/CA21HB = 1.01). DNA from another individual (Ma I-2) with a different C4A gene duplication (C4A*3,A*5,C4B*QO) also had equal densitometry measurements (7.0/6.0 kb = 1.07). We conclude that two extended haplotypes from unrelated pedigrees have two C4 genes and both C4 genes encode separate C4A alleles. These findings are compatible with a gene conversion event of C4B to C4A.     

Gene organization of haplotypes expressing two different C4A allotypes

Summary The gene organization of C4 haplotypes expressing two different C4A allotypes with a C4B null allele (C4A3A2-BQ0 and C4A3A6BQO) was studied using Southern blot analysis with cDNA probes and restriction enzymes which give C4A and C4B locus-specific restriction fragments. These haplotypes were shown to have both a C4A and a C4B locus present, suggesting that the C4B locus expresses a C4A protein. The finding of a 21-OH A and a 21-OH B gene on the C4A3A6BQO haplotype further suggests that this haplotype has the common gene organization C4A, 21-OH A, C4B, 21-OH B. A model explaining C4 null alleles on haplotypes found to have two C4 loci is presented.     

Polymorphism of pig serum alpha-protease inhibitor-3 (PI3) and assignment of the locus to the Pi1, Po1A, Po1B, Pi2, Igh linkage group

Polymorphism of an alpha-protease inhibitor, PI3, in pig serum samples was detected using 2D agarose gel (pH 5.4)--polyacrylamide gel (pH 9.0) electrophoresis. Evidence was obtained that the five variants observed (A, B1, B2, C and D) are under genetic control by codominant alleles (Pi3A, Pi3B1, Pi3B2, Pi3C and Pi3D) at one autosomal locus. Variants A, B1, B2 and C inhibited chymotrypsin; there was no appreciable inhibition of trypsin and papain. Variant D did not inhibit chymotrypsin, and therefore its classification as a PI3 variant was put in question. PI3 typing was not possible in about 50% of the studied pigs since in those cases the PI3 variants were either too weak or absent. On the basis of backcross matings and haplotyping in complete families for protease inhibitor loci Pi1, Po1A, Pi2 and Pi3 it was proved that the Pi3 locus belongs to the protease inhibitor gene cluster, and the position of the locus in the linkage group was proposed as being Pi1-Po1A-(Po1B)-Pi3-Pi2-(Igh1, Igh2, Igh3, Igh4).     

C8A and C8B polymorphisms in Norwegians and Norwegian lapps

C8 inheritance patterns in 364 mother-child pairs formed the basis for evaluation of the existence of silent alleles (null alleles) in the genes determining the two known polymorphic C8 systems. While evidence for such alleles was not found in C8A (alpha-gamma complex), two observations of null allele segregation in C8B (beta chain) indicate a C8BQ*0 allele frequency of about 0.07. Two population samples comprising 150 Lappish and 1,264 non-Lappish Norwegians were examined for phenotype distributions in C8A and C8B. The phenotype distributions were mainly in accordance with the expected Hardy-Weinberg distribution. The results for C8A indicated simple, codominant inheritance of two frequent and several rare alleles. Allele frequencies were similar in the two populations. The C8A B gene frequency in Norwegians was significantly lower than that in FRG and higher than that in Negroes. C8B allele frequencies were also calculated from gene counts in the population material, but with due corrections for the C8BQ*0 frequency observed in the mother-child material.     

Definitive RFLPs to distinguish between the human complement C4A/C4B isotypes and the major Rodgers/Chido determinants: Application to the study of C4 null alleles

Definitive restriction fragment length polymorphisms (RFLPs) representing the exact locations responsible for isotypicity between the human complement components C4A and C4B, and their generally associated major Rodgers (Rg1) and Chido (Ch1) antigenic determinants, have been designed. By means of a C4d-specific genomic probe for Southern blot analysis, a C4A gene can be defined by the presence of the 276 bp and 191 bp N 1 a IV fragments, while a C4B gene can be defined by a single 467 bp N1aIV fragment. In addition, an Rgl-expressing C4 gene can be represented by a 565 bp EcoO 109 fragment, and a Chl-expressing C4 gene by a 458 by EcoO 109 fragment, under the same conditions. All these polymorphic restriction fragments can be unambiguously and conveniently detected. In combination with the Taq I polymorphic patterns specific for the C4 loci and for the neighboring 21-hydroxylase genes, the nature and structure of the tandem C4,21-hydroxylase gene complex can be elucidated. In this study, it is inferred that the null allele of the HLA haplotype B44 DR6 C4A3 C4BQO is not a C4B allele, but probably encodes another C4A 3 allotype at the second C4 locus.Abbreviations used in this paper C4 (long) - C4 gene of 22 kb, with a 6–7 kb intron - C4 (short) - C4 gene of 16 kb, without a 6–7 kb intron; complotype SCO1, factor B S, C2 C, C4A QO; C4B 1 Dedicated to the memory of our teacher, the late Professor Rodney Porter C. H. F. R. S.