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1.
以普通小麦A552为父本、IRS/IBL黑麦和小麦易位系早抗为母本的杂种S3063,经C-分带和原位杂交鉴定,发现丢失了母本的黑麦成分,同时又发生了小麦种内易位,变成了5BS/7BS、5BL/7BL臂间双易位系。与此同时,白粉病抗性和一些农艺性状也发生了变化,此已己连续3年对白粉病免疫,且免疫条锈、叶锈和高抗黄矮病,每公顷5523千克,接近北京推广品种京冬6号  相似文献   

2.
本文采用计算机模拟的方法,对有限群体中基因频率的概率分布进行了研究。The probability distribution of gene frequency was studied by simulative method in finite population.  相似文献   

3.
兴安盟3个民族10对性状的基因频率   总被引:24,自引:3,他引:24       下载免费PDF全文
调查了内蒙古兴安盟汉、蒙古、朝鲜族的10对遗传性状,并计算了各民族每一性状的基因频率,同时也进行了民族间基因频率的比较。比较结果显示:汉族-朝鲜族间差异较大,蒙古族-朝鲜族间次之,汉族-蒙古族间差异较小。Abstract:Ten genetic traits were investigated in Han,Mongol and Chaoxian nationalities in Xing'an League of Inner Mongolia.The gene frequency of the traits was calculated in each nationality and compared between the nationalities.The result indicated that the difference of gene frequency between Han and Chaoxian nationalities was significant,followed by between Mongol and Chaoxian ones,whileit was relatively insignificant between Han and Mongol ones.  相似文献   

4.
中国人群基因频率的主成分分析   总被引:1,自引:0,他引:1  
对中国人群中38个基因座的130个等位基因的频率进行了主成分分析, 绘制了主成分分布地图和主成分综合地图. 结果显示, 汉族人群的第1主成分分布反映了南方蒙古人种与北方蒙古人种间遗传结构差异的梯度变化, 而其第2主成分分布则反映了蒙古人种与高加索人种间的基因流动. 中国少数民族人群的第1主成分分布与汉族中的第2主成分相似, 而第2主成分分布则与汉族中的第1主成分相似. 当将中国汉族与少数民族的基因频率放在一起分析时, 所得出的主成分分布基本上与少数民族的相似. 中国人群基因频率的第3, 4主成分的分布则可能反映了古代某些地区人口骤增而向外扩展的历史事件. 中国人群基因频率主成分综合地图明显地显示出: 在亚洲的南、北方蒙古人种间有一明显的分界线--长江. 猜测: 如果中国现代人确实起源于非洲, 则南、北方蒙古人种的祖先在进入亚洲以前已经分开, 南方蒙古人种的祖先自非洲或中东沿海岸向东迁徙、扩展、直至东南亚, 然后折向北, 至华南, 再直至长江, 甚至可能有一段时间曾占据过长江以北的一些地区. 北方蒙古人种的祖先则在帕米尔以北地区自西向东, 直至东北亚, 再扩展至美洲、日本等地, 同时向南, 直至长江. 在近二三千年内, 北方蒙古人种才不断向长江以南扩展、渗透.  相似文献   

5.
新疆四个民族八对遗传性状的基因频率   总被引:15,自引:1,他引:14  
在调查新疆维吾尔、哈萨克、柯尔克孜、塔吉克族8对遗传性状的基础上分别计算出8对遗传性状在上述4个民族中的基因频率, 并进行了4个民族之间基因频率的比较。比较结果表明:塔吉克与其他3个民族之间基因频率的差异显著,而哈族与柯族之间的差异不显著。Abstract:Acoording to the investigation of eight pairs of genetic traits among four minorities in Xinjiang (Uygur,Kazak,Kirgiz and Tajik),the gene frequencies of these traits were respectively calculated and compared.The results indicated that the difference of gene frequencies between Tajik and other three populations significant,while it is insignificant between kazak and Kirgiz.  相似文献   

6.
本文调查了中国汉族及荷兰高加索群体中人类vWF基因内含子40 nt 31/2 215~2 380 区域 HUMFA 31(C) 遗传多态性的基因频率及基因型频率分布。并对两群体之间的分布以拟然比方法进行比较。对9个等位基因片段测序的结果表明, 在nt 31/2 234~2 265区域也有变异存在。提示该座位当被测等位基因DNA片段长度相同时,仍可能存在遗传差异。Abstract The allele frequencies and phenotype distribution of humanvWFgene intron 40 in the region of nt 31/2 215~2 380 (HUMFA 31(C)) were investigated in the population of the Netherlands and China. The data between two populations were compared by likelihood ratio test. Nine alleles were sequenced and the polymorphism of region of nt 31/2 234~2 265 was revealed.  相似文献   

7.
云南省三个地方鸡种血液淀粉酶多态性分析   总被引:3,自引:0,他引:3  
采用垂直平板聚丙烯酰胺凝胶电泳法,测定了版纳斗鸡、武定鸡、尼西鸡的血液淀粉酶(Amy)。发现云南3个地方鸡种Amy-1的AA、BB型纯合子基因型频率很低, 其中尼西鸡为0,而AB型杂合子基因型频率很高,杂合子显著过量,均偏离Hardy-Weinberg平衡。在版纳斗鸡少数个体中还发现控制血液淀粉酶的另一位点Amy-2。Abstract:Blood amylase polymorphism in 3 Yunnan local chicken breeds(Banna ganme chicken,Wuding chicken.Nixi chicken)was determined with polyacrylamide gel electrophoresis,It was found that frequen cies of both AA and BB homozygous genotype were very low,while AB heterozyote genotype frequency was very high in 3 Yunnan local chicken breeds and that Amy-1 distribution in these breeds was widely deviated from Hardy-Weinberg equilibrium proportion.We have also found that there is another locus Amy-2 which controls the amylase in a few Banna game chickens.  相似文献   

8.
中国人群的等位基因地理分布图   总被引:11,自引:2,他引:11  
发表了我国首批绘制的人类基因地理分布图,包括12个等位基因,即ABO系统的I^B,I^O,MNS系统的m,Rh-D,HLA系统的A1与A11,人体免疫球蛋白的Gm^1;21与Gm^1,3;5,AK^1,G6PD缺陷型,以及PTC味盲基因。这些基因地理不仅显示了等位基因的地理分布状况,也可用于研究某些等位基因的起源与扩散,基因流动以及某些环境因子通过选择对某些等位基因频率的影响。  相似文献   

9.
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To test gene exchange between Equatorial and Mongolian populations in ancient continental China, Equatorial racial characters are examined and average frequencies of Equatorial racial characters are calculated for each of 8 cranial sample groups in this study. The results indicate that: 1) Equatorial racial characters can be found in the samples from ancient and modern China , and gene exchange events occurred in ancient continent China as early as 3000~2000 years BP. 2) The average frequencies of Equatorial racial characters decrease in the ancient populations from eastern to western, and appear a reverse pattern when compared with their average frequencies of Eurasian racial characters. An overlapping model, opposite gene flows occurring during the periods of 3000~2000 BP, is proposed.  相似文献   

10.
为探讨中国大陆古代人群与赤道人种人群之间的基因交流情况,本项研究对赤道人种的若干特征在中国古代人群头骨中的出现情况作检测。检测的材料包括3800~1200年前生活在新疆、青海、宁夏和河南安阳的12组人群的头骨以及现代华北和云南的人类头骨。结果表明:1)赤道人种若干特征能够在我国古代多个地区的人群中和现代华北和云南人群中检测到,表明中国大陆至少在3000~2000年前已存在赤道人种基因流入蒙古人种的人群之中的现象;2)赤道人种特征平均出现率在中国古代人群中很可能在地理上大致是由东向西递降,与当时这些人群中的欧亚人种特征平均出现率的地理上分布趋势呈相反方向,提示了在中国大陆至少在距今3000-2000年期间已经存在两个相反流向的外来\"基因流\"。  相似文献   

11.
Summary A method for quantifying mating behavior in clonal seed orchards of forest tree species is presented. It involves the estimation of effective numbers of pollen parents from seed samples collected from individual ramets in such orchards. These effective numbers are variance effective numbers for populations of male gametes that are successful in uniting with ovules to produce viable seed. Three such effective numbers are defined for clonal seed orchards:N p (a) for male gamete populations for ramets within clones,N p (b) for male gamete populations for clones, andN p (c) for male gamete populations for entire orchards. Estimators for these effective numbers and for standardized variances of allele frequencies in the male gametic populations are presented. Expressions are also given for the confidence intervals for each of the three effective numbers. Estimates of these parameters and the corresponding confidence intervals for two seed orchards are presented and interpreted.  相似文献   

12.
中国地方鸡种血液淀粉酶Amy-1多态性   总被引:15,自引:1,他引:14  
本文用聚丙烯酰胺水平凝胶电泳法测定了我国 10个地方鸡种的血液淀粉酶Amy-1多态性,发现我国地方鸡种Amy-1的AA、BB型纯合子基因型频率很低, AB型基因型频率很高,杂合子显著过量,且普遍存在Amy-1分布不平衡。还发现Amy-1A和Amy-1B两个等位基因频率在所有10个鸡种中几乎均为0.5。Abstract:Blood amylase-1 polymorphism in 10 Chinese native chicken breeds was determined with polyacrylamide horizontal gel electrophoresis.It was found that both AA and BB genotype frequencies were very low,but AB genotype frequency was very high in Chinese native chicken breeds and that amylase-1 distribution in these breeds was widely deviated from Hardy-Weinberg equilibrum proportion.Both Amy-1A and Amy-1B gene frequencies were nearly 0.5 in all 10 breeds.  相似文献   

13.
The frequency of cyanogenesis of 48 species of vascular plants was examined by testing 30 individuals from five populations of each species for release of cyanide. The rate at which cyanide was released and the amount of cyanide released varied widely among individuals of a population and among populations of a species. For many taxa, the frequency of cyanogenesis was highly variable among populations. Of the species examined, 20 have not been reported previously as being cyanogenic.  相似文献   

14.
Rau M. E. 1979. The frequency distribution of Hymenolepis diminuta cysticercoids in natural, sympatric populations of Tenebrio molitor and T. obscurus. International Journal for Parasitology9: 85–87. Natural, sympatric populations of Tenebrio molitor and T. obscurus were examined for cysticercoids of Hymemlepis diminuta. The distribution of cysticeroids in both species and both sexes conformed to the negative binomial. Cysticeroids were more prevalent and the mean intensity of infection was higher in T. obscurus than in T. molitor. No differences in the intensity of infection were detected between the sexes. Larvae of both beetle species were always very lightly infected. The significance of these factors in the transmission of the infection to the rat definitive host is discussed.  相似文献   

15.
The first rare Jk(a-b-) type in China was found in Han, Henan Province, but no moreJk(a-b-) in the proband's family. Her parents and sibs were Jk(a+b-) type and her hu-sband and children were Jk(a-b+) type. The second Jk(a-b-) was found in Hakka, MeiCounty, Guangdong Province, four months later. This proband is a young unmarried woman.No antibody was found in both of these two proband' sera. Up to now Jk(a- b- ) phenotypefrequency in Chinese is 0.03%, and the gene frequency is 0.0202.  相似文献   

16.
在河南汉族中发现了国内首例稀有的JK(a-b-)红细胞血型。家系调查未发现第二例。先证者父母及同胞均为Jk(a+b-)型,丈夫及儿子均为Jk(a-b+)型。四个月后在广东梅县客家人中又发现一例JK(a-b-)型,先证者为一未婚女子。两位先证者血清中均无抗体。到目前为止,JK(a-b-)型在中国人群中的分布频率为2/6391(0.03%)Jk基因频率为0.0202。  相似文献   

17.
From 420 records of ethnic locations and movements since 2000 B. C., we computed vectors describing the proportions which peoples of the various European language families contributed to the gene pools within 85 land-based 5 × 5-degree quadrats in Europe. Using these language family vectors, we computed ethnohistorical affinities as arc distances between all pairs of the 85 quadrats. These affinities are significantly correlated with genetic distances based on 26 genetic systems, even when geographic distances, a common causative factor, are held constant. Thus, the ethnohistorical distances explain a significant amount of the genetic variation observed in modern populations. Randomizations of the records by chronology result in loss of significance for the observed partial correlation between genetics and ethnohistory, when geography is held constant. However, a randomization of records by location only results in reduced significance. Thus, while the historical sequence of the movements does not seem to matter in Europe, their geographic locations do. We discuss the implications of these findings. © 1993 Wiley-Liss, Inc.  相似文献   

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