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1.
P. Bijma  JAM. Van-Arendonk    H. Bovenhuis 《Genetics》1997,145(4):1243-1249
Under gynogenetic reproduction, offspring receive genes only from their dams and completely homozygous offspring are produced within one generation. When gynogenetic reproduction is applied to fully inbred individuals, homozygous clone lines are produced. A mixed model method was developed for breeding value and variance component estimation in gynogenetic families, which requires the inverse of the numerator relationship matrix. A general method for creating the inverse for a population with unusual relationships between animals is presented, which reduces to simple rules as is illustrated for gynogenetic populations. The presence of clones in gynogenetic populations causes singularity of the numerator relationship matrix. However, clones can be regarded as repeated observations of the same genotype, which can be accommodated by modifying the incidence matrix, and by considering only unique genotypes in the estimation procedure. Optimum gynogenetic sib family sizes for estimating heritabilities and estimates of their accuracy were derived and compared to those for conventional full-sib designs. This was done by means of a deterministic derivation and by stochastic simulation using Gibbs sampling. Optimum family sizes were smallest for gynogenetic families. Only for low heritabilities, there was a small advantage in accuracy under the gynogenetic design.  相似文献   

2.
运用RAPD技术对连续二代人工雌核发育鲢的遗传多样性及异源遗传物质的整入进行了分析 ,结果表明 :一代雌核发育鲢 ,个体间遗传相似度为 0 94 5— 0 995 6 ,多样性指数为 0 175 ;二代雌核发育鲢 ,个体间遗传相似度为0 96 15— 1 0 0 ,平均为 0 985 2 ,多样性指数为 0 0 6 2。研究揭示经过连续二代人工雌核发育后 ,其遗传多样性明显减少 ,种质进一步纯化。通过对雌核发育鲢二代、亲本鲢和雄鲤的RAPD扩增比较 ,发现雌核发育鲢含有少数与父本相同的特异DNA扩增带 ,而亲本鲢没有 ,在基因水平上表明雌核发育鲢整入了雄鲤的遗传物质  相似文献   

3.
草鱼雌核发育后代不同群体的微卫星遗传分析及指纹识别   总被引:2,自引:0,他引:2  
以紫外线灭活的团头鲂精子激活草鱼卵子,冷休克抑制第二极体排出的方法诱导出长江水系优良F2代草鱼减数雌核发育子代。在后代中不仅存在雌核发育后代,还存在草鲂杂交后代,雌核发育后代的体型与草鱼一致,而草鲂杂交后代的体型介于草鱼与团头鲂之间。Partec CyFlow倍性分析仪测定结果显示:普通草鱼与雌核发育草鱼的相对DNA含量分别为23.01和22.72,二者的DNA含量接近;而高体型子代的相对DNA含量为25.38,介于草鱼与团头鲂(DNA含量28.21)之间,属于草鲂杂交后代。选取17个微卫星标记对草鱼群体、雌核发育草鱼群体和草鲂杂交后代的遗传多样性进行了检测,共检测出59个等位基因,其中43.18个有效等位基因。草鱼对照群体、草鲂杂交后代和雌核发育草鱼群体的平均等位基因依次为3.57、2.86和2.79,平均有效等位基因依次为2.93、2.37和1.96,平均期望杂合度在依次为0.6502、0.5573和0.3775,多态信息含量(PIC)平均值依次为0.5738、0.4649和0.3791。与草鱼对照群体相比,雌核发育草鱼群体的遗传多样性显著下降,表明通过减数雌核发育方法可获得纯合性较高的草鱼个体。构建了草鱼后代不同群体的DNA指纹模式图,筛选到不同群体的9个特异微卫星标记,为草鱼优良群体的选育提供了基础资料。  相似文献   

4.
Second-generation gynogenetic channel catfish were characterized by molecular and immunologic assays to determine if they were isogenic at major histocompatibility complex loci. Southern blot analyses, using channel catfish MHC class II B and class I A gene probes, revealed identical banding patterns among second-generation gynogenetic fish. In contrast, banding patterns from outbred fish differed not only from gynogenetic animals, but also among themselves. Nucleotide sequence analysis of the MHC class II β1 domain, which encompasses the peptide binding region, from four randomly selected gynogenetic fish showed a single DNA sequence. In contrast, analysis of the same region from three outbred fish showed sequences that differed not only among themselves, but also from those of gynogenetic animals. In cytotoxic assays, peripheral blood leukocytes from outbred fish lysed both gynogenetic and allogeneic targets, whereas those from gynogenetic fish lysed only allogeneic targets. Taken together, these results suggest that this group of second-generation gynogenetic channel catfish is isogenic at MHC loci and may provide an excellent system with which to study cell-mediated immunity in teleosts. Received September 11, 1998; accepted January 14, 1999  相似文献   

5.
Gynogenesis was used to map eight loci to their centromeres in Xenopus laevis. Several loci remote from their centromeres were identified. This information may be useful in distinguishing gynogenetic diploid progeny produced by suppression of second polar bodies from gynogenetic diploid progeny homozygous at all loci produced by suppression of first cleavage of gynogenetic haploids.  相似文献   

6.
杨江义  李旭锋 《植物学报》2002,19(5):552-559
对单倍体的用途和来源作了简略的概括。回顾了通过离体诱导获得雌性单倍体的研究历程,并分析了这一方法的优势。离体诱导雌性单倍体的效果受到供体植株的基因型、供体植株的生理状态、胚囊发育时期、材料预处理、花器附属物、培养基、培养方式、培养条件等一系列因素的影响。对这些影响因子的有关研究进行了系统的总结。在雌性单倍体的个体发育方面,对一些有代表性的实验结果进行了总结。  相似文献   

7.
Grass carp (Ctenopharyngodon idellus) eggs were activated by UV-irradiated diploid sperm of allotetraploid hybrids derived from red crucian carp (♀)?×?common carp (♂) and then duplicated by cold shock in 4-6°C water for 10-12 min. Different cold shock initiation times resulted in two types of diploid gynogenetic grass carp: meiotic gynogenetic (meiG) and mitotic gynogenetic (mitG). Over a 5-year period, a total of 17,170 meiG and 1,080 mitG fry were produced and 6,862 meiG and 372 mitG grass carp survived. The gynogenetic fish were confirmed by morphological characteristics, chromosome examination, and microsatellite DNA analysis. The morphological traits of the gynogenetic grass carp were similar to those of wild diploid grass carp. Normal gynogenetic fish were identified as diploid with 48 chromosomes by chromosomal metaphases examination, while nonviable abnormal embryos were detected as haploid with 24 chromosomes. Microsatellite DNA analysis indicated that after one generation of gynogenesis, the genetic purity of meiG and mitG grass carp was significantly increased over that of wild grass carp. In addition, both meiG and mitG grass carp groups were 100% female, and 88% of these showed normal ovary development. Thus, the sex determination mechanism in female grass carp was homogamety. The ability to establish pure all-female groups of meiG and mitG grass carp should be a valuable contribution to both fish genetics and grass carp breeding.  相似文献   

8.
杨书婷  桂建芳 《遗传》2000,22(4):221-224
以雌核发育银鲫和两性生殖彩鲫的成熟卵为材料,分离卵壳,经处理得到卵壳可溶性蛋白组分。SDS-PAGE梯度凝胶电泳分析在雌核发育银鲫中揭示出3条较明显的差异蛋白带。同时,采用相同处理方法对受精前后卵壳蛋白组分进行比较分析后发现,这些差异蛋白带在受精后发生了变化,其带纹表现为减弱或消失,表明这些差异蛋白可能与受精过程相关。 Abstracts:Egg chorions were isolated from unfertilized and fertilized eggs of gynogenetic silver crucian carp and gonochoristic color crucian carp by homogenization and further purification techniques.Then,soluble proteins were extracted from the isolated egg chorions,and were analyzed by gradient SDS-PAGE.Three differential protein bands were revealed between the gynogenetic silver crucian carp and gonochoristic color crucian carp.Furthermore,these differential proteins were demonstrated to undergo obvious changes during fertilization.It was suggested that these differential proteins should be related to the special fertilization process in gynogenetic silver crucian carp.  相似文献   

9.
两个人工雌核发育红白锦鲤群体的RAPD标记分析   总被引:23,自引:3,他引:20  
采用PAPD方法,对两个人工雌核发育红白锦鲤群体进行了多态性及分子标记分析。结果表明,同一雌核发育群体具有基本一致的扩增产物,而不同雌核发育群体间的扩增产物则有较大不同;并从30个随机引物的扩增谱带中找到了7个引物(Opo-7,Opo-9,Opo-12,Opo-14,Opj-4,Opj-8和Opj-10)的扩增谱带可以作为两个不同雌核发育群体间的遗传标记。由UPGMA聚类法构建的分支系统树清晰地反映了两个雌核发育群体及其个体间的相互关系。  相似文献   

10.
植物雌性单倍体的离体诱导   总被引:7,自引:0,他引:7  
杨江义  李旭锋 《植物学通报》2002,19(5):552-559,574
对单倍体的用途和来源作了简略的概括。回顾了通过离体诱导获得雌性单倍体的研究历程 ,并分析了这一方法的优势。离体诱导雌性单倍体的效果受到供体植株的基因型、供体植株的生理状态、胚囊发育时期、材料预处理、花器附属物、培养基、培养方式、培养条件等一系列因素的影响。对这些影响因子的有关研究进行了系统的总结。在雌性单倍体的个体发育方面 ,对一些有代表性的实验结果进行了总结  相似文献   

11.
组织移植对银鲫不同雌核发育系的遗传监测   总被引:11,自引:1,他引:10  
采用脾移植实验对银鲫3个不同的雌核发育系进行了遗传分析。在3个同系移植的组合中,移植物被接受的个体数平均达95%,表明同一雌核发育系的大多数个体具有一致的基因型。在不同雌核发育系间的移植,移植物在7—14天被排斥(21—30℃)。从而用组织移植证明这些雌核发育系是存在的,并与遗传标记所鉴别的结果一致。文中对同系移植中出现少数排斥现象的原因进行了讨论。    相似文献   

12.
Survival, growth and sex ratios of gynogenetic diploid honmoroko   总被引:1,自引:0,他引:1  
Survival, growth and sex ratios of gynogenetic diploid honmoroko Gnathopogon caerulescens induced by blocking the release of the second polar body were examined. Mean survival of gynogenetic juveniles at 130 days after hatching was about 33% lower than that of the controls. No significant difference was seen in early growth between control and gynogenetic diploids. Standard length and body weight in six groups of gynogenetic progeny were significantly greater but in two groups were significantly smaller than in the controls. Although 69% of gynogenetic diploids had well-developed gonads, the remaining 30% had undeveloped gonads (small in size or thread-like), and those gonads were divided into four types. The mean proportion of females in the 10 gynogenetic groups was 87·2% which was significantly ( P <0·01) higher than in the controls (44·7%). Gynogenetic diploids included 3·0–35·3% males. Most of those males produced a high proportion of female progeny, but the proportion of male offspring varied widely. From these results, the sex determining mechanism in honmoroko was presumed to be female homogamety, but other factors resulted in the production of males.  相似文献   

13.
两个雌核发育白鲢群体同工酶分析及遗传标记的确定   总被引:4,自引:0,他引:4  
取源于武汉两个不同渔场两尾白鲢的卵子,经紫外照射遗传物质失活的鲤鱼精子刺激雌核发育和热休克诱导第二极体保留的基因组操作技术,获得了两个不同的人工雌核发育白鲢群体。采用聚丙烯酰胺垂直板电泳技术,分析了这两个不同人工雌核发育白鲢群体(分别称为Hy-G1和Hy-G2)内不同个体的肝脏、肌肉组织以及红细胞中乳酸脱氢酶(LDH)、苹果酸脱氢酶(MDH)、酯酶(EST)、超氧化物歧化酶(SOD)等几种同工酶的表达谱式,并与普通繁殖的同龄白鲢进行了比较。结果表明,各个雌核发育白鲢群体内不同个体间的酶谱表现出很大程度的一致性,具较高的纯合度,而两个不同雌核发育群体Hy-G1和Hy-G2之间表现有明显差异。特别是肝脏和肌肉组织迁移率较快的酯酶谱带等以其稳定的差异,建议作为区分这两个人工雌核发育白鲢群体的生化遗传标记。    相似文献   

14.
N B Cherfas 《Genetika》1975,11(7):78-86
Mass lost of diploid gynogenetic carp offspring were obtained with the use of fish-farm method of reproduction. The average yield of gynogenetic diploids in usual experiments was 0.1% (from fertilized eggs). The cooling of unfertilized spawn (at the stage of metaphase II) to 8--10 degrees C during 3.5--4.5 hours in 50% of cases permitted to increase by tens of times (in the most successful experiments up to 8%) the yield of gynogenetic diploids. The rate of survival of carps remained relatively low during the first two years of life, particularly during the first hibernation that is a critical period. No specific depression of growth in gynogenetic diploid carps was observed. A high yield of gynogenetic diploids (3.9% of fertilized eggs) and their relatively high rate of survival were observed in the second generation of artificially induced gynogenesis.  相似文献   

15.
结合差速离心法、饱和酚/氯仿/异戊醇抽提等技术.提取并纯化了雌核发育草鱼近交F.代的线粒体DNA(mtDNA).用8种限制性内切酶对mtDNA酶切分析.结果表明:雌核发育草鱼近交Fl代mtDNA分子大小为16、77kb,除无sail酶切位点外,其余7种酶EcoRI、BalI、。YbaI、BarnHI、PstI、XhoI各产生4、4、3、3、3、2、2个切点。与已报道的普通草鱼一致.雌核发育草鱼近交F1代与普通草鱼间未检测出限制性片断长度多态性差异、这表明,雌核发育草鱼F。代与普通草鱼mtDNA遗传结构具有同一性、  相似文献   

16.
The production of Atlantic salmon gynogenomes by the combined use of a novel method for sperm irradiation and differently timed high hydrostatic pressure shocks is described. Sperm solutions were exposed to UV irradiation in a temperature-controlled flow-through device. Eggs fertilised with such sperm were exposed to shocks of 9500 psi at 30 min or approximately 7 h after fertilisation in order to produce meiotic and mitotic gynogenomes respectively. Yields of meiotic gynogenomes were generally high (up to 95%); those of mitotic gynogenomes were lower (range 2–20%). Analyses of the offspring by ploidy status and fingerprinting confirmed their gynogenetic origin. Small numbers of mitotic gynogenetic fish were grown on for 2 years in fresh and salt water. S1/S2 ratios were lower in gynogenetic fish and mean age at maturity was greater. Of the presumptive gynogenetic fish subjected to destructive sampling (n = 87) all were female.  相似文献   

17.
锦鲤4个人工雌核发育家系的微卫星标记研究   总被引:33,自引:4,他引:33  
利用Crooijmans et al.(1997)分离的包含CA重复单元的普通鲤鱼(Cyprinus carpio L.)的8个微卫星DNA标记,对从锦鲤(Cyprinus carpio L.)的红白,大正和昭和3个不同品系中所获得的4个不同人工雌核发育家系的20尾个体进行PCR扩增。电泳结果表明,8对引物在20尾个体中均能重复稳定地扩增出相应的同源序列。随引物不同,各等位基因数为1-11个,大小在68-264bp。在MFW4,MFW7,MFW19,MFW20,MFW23和MFW24 6个微卫星的扩增结果中,20尾个体的扩增图谱呈现了高度的遗传多态性,不同雌核发育家系内个体的遗传异质性也较大。其中大正(TaS)和红白1(RW1)的个体不仅花色分化显著,而且个体间的平均遗传距离分别高达0.28。通过对微卫星等位基因和基因型分析发现,由于锦鲤品系中的每一个体是通过不断地杂交选育而获得,基因组来源复杂,基因高度杂合。因此,只进行1代的人工雌核发育,其家系内仅部分个体的部分座位出现纯合。所获得的人工雌核发育锦鲤为后续的色素遗传调控机制研究提供了必要的实验材料;同时,所鉴定的微卫星分子标记为进行锦鲤的分子标记育种的基因组作图提供了理想的工具。  相似文献   

18.
To study immunological and immunogenetical parameters related to resistance against viral haemorrhagic septicaemia (VHS), attempts to make gynogenetic strains of rainbow trout selected for high and low resistance to VHS were initiated in 1988. The first gynogenetic generation of inbreeding resulted in the more resistant offspring E8 and the low resistance offspring K3; the K3 offspring having the same high mortality as the susceptible reference strain of outbred trout in infection trials. A second gynogenetic generation derived from the E8 strain resulted in some low resistance offspring, and two gynogenetic families in which all, or nearly all, fish survived challenge with VHS virus. In this study, an attempt to associate the distribution of different MHC class II genotypes with low and high resistance gynogenetic offspring was performed. Two different MHC haplotypes could be distinguished, and in both low and high resistance families all three genotypes were found, which could be explained by the fact that the mother fish carried the heterozygous genotype. Although no significant differences in MHC II genotypes were found between the high and low resistance offspring, a significantly different distribution of haplotypes in the low resistance offspring was observed, that could not be explained by a one- or two-locus model.  相似文献   

19.
雌核发育团头鲂的形态和遗传特征分析   总被引:2,自引:0,他引:2  
利用团头鲂(Megalobrama amblycephala)正常二倍体群体作为对照组, 对团头鲂减数分裂雌核发育二倍体群体的形态特征、染色体组型、性腺发育及遗传特征进行了分析. 结果表明: 雌核发育群体与正常群体在外部可数、可量性状上没有显著性差异(P0.05); 但雌核发育群体出现了尾鳍条数为12的畸形个体, 与正常个体之间有较大的差异; 两个群体的染色体条数都是48, 核型均为18 m+26 sm+4 st; 观察了20尾雌核发育个体的性腺, 均为雌性个体且卵巢发育良好; 采用10个微卫星标记对2个群体的遗传多样性分析, 结果表明正常群体和雌核发育群体平均等位基因数分别为3.8个和1.7个, 雌核发育群体的多态性显著低于正常群体, 表明减数分裂雌核发育二倍体具有高度的遗传相似性, 可作为一个很好的育种材料.    相似文献   

20.
DNA content and chromosome numbers were studied in gynogenetic and normal carp embryos. Gynogenetic embryos showed the haploid chromosome number; the occurrence of spontaneous diploidization was rare. Early cold shock treatment of the gynogenetic zygotes resulted in the retention of the second polar body producing a much higher proportion of normally developing viable larvae. The appearance of large numbers of aneuploid embryos in the cold-treated gynogenetic group is explained by the loss or breakdown of chromosomes that are caused in their turn by the absorbtion of the second polar body through the cold treatment.  相似文献   

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