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排序方式: 共有136条查询结果,搜索用时 15 毫秒
1.
目的比较大耳白黑眼兔(WHBE兔)与日本大耳白兔(JW兔)和新西澜兔(NZW兔)血液蛋白的多态性,从分子水平了解WHBE兔特殊性状的遗传背景。方法采用聚丙烯酰胺凝胶电泳对WHBE兔、JW兔和NZW兔血液中的前白蛋白(Pr),后白蛋白(Po),前转铁蛋白1(Prt1),前转铁蛋白2(Prt2),转铁蛋白1(Tf1),转铁蛋白2(Tf2),后转铁蛋白(Ptf),慢α球蛋白(Sag)、血红蛋白(Hbα、Hbβ)和白蛋白(Alb)共11个蛋白位点进行检测。结果Pr、Ptf、Hbα、Hbβ、Alb、Po、Sag和Prt2在所有实验兔个体中的表型一致,而Tf1、Tf2和Prt1的表型在各实验兔品系间存在显著差异。在Tf1位点,NZW兔以BC表型为主,无AA型;JW兔只有AA型,而WHBE兔以AB型为主。在Tf2位点,NZW兔有AA型,而JW兔和WHBE兔无AA型。在Prt1位点,NZW兔无AB、BB和BC表型而有AC表型。NZW兔蛋白位点的平均杂合度大于JW兔和WHBE兔。JW兔与WHBE兔的遗传距离最近。结论Tf1、Tf2和Prt1可作为区分NZW兔、JW兔和WHBE兔的特征标记,并且与WHBE兔特殊性状形成有关。JW兔与WHBE兔的亲缘关系最近。 相似文献
2.
Naofumi Nomura Kento Fujiwara Tokushiro Takaso Motomi Ito Koichi Uehara Hiroaki Setoguchi 《Conservation Genetics》2009,10(4):1093-1095
Eight microsatellite loci for the perennial herb Farfugium japonicum, including the rheophytic variety luchuense endemic to riparian areas of the Ryukyu Islands, Japan, were isolated and characterised. The number of alleles ranged from
5 to 14. The expected (H
E) and observed (H
O) heterozygosities were 0.344–0.885 and 0.121–0.754, respectively, from 69 individuals in one population. Six loci exhibited
significantly fewer heterozygotes than expected under Hardy–Weinberg equilibrium (P < 0.05). The primers amplifying microsatellite sequences in F. japonicum may provide a population genetics tool useful in the establishment of a conservation strategy. 相似文献
3.
大河猪76个STR基因座的遗传多态性 总被引:4,自引:1,他引:3
大河猪是中国西南中海拔地区代表性猪种之一,长期以来在当地养猪生产中发挥了重要作用。为了阐明其群体遗传变异情况,为进一步有效保护和合理利用提供科学依据,采用分布在家猪19对染色体上的76个微卫星标记对该猪种60个随机抽样个体进行了微卫星PCR–聚丙烯酰胺凝胶电泳检测。共检测到347个等位基因,所有座位都呈现出多态性,每个座位的等位基因数在3—10个之间,平均每个座位等位基因数4.57个,有效等位基因数3.50个,群体平均杂合度及平均多态信息含量分别为0.696 2±0.071 6和0.644 1±0.091 4。结果表明,大河猪群体遗传多样性较丰富,选择潜力较大。 相似文献
4.
Frugivorous animals frequently generate clumped distributions of seeds away from source trees, but genetic consequences of this phenomenon remain poorly resolved. Seed dispersal of the palm Oenocarpus bataua by long-wattled umbrellabirds Cephalopterus penduliger generates high seed densities in leks (i.e., multi-male display sites), providing a suitable venue to investigate how dispersal by this frugivore may influence seed source diversity and genetic structure at local and landscape levels. We found moderate levels of maternal seed source diversity in primary seed rain across five leks in northwest Ecuador (unweighted mean alpha diversity α = 9.52, weighted mean αr = 3.52), with considerable variation among leks (αr range: 1.81–24.55). Qualitatively similar findings were obtained for allelic diversity and heterozygosity. Higher densities of O. bataua adults around leks were associated with higher values of αr and heterozygosity (non-significant trends) and allelic diversity (significant correlation). Seed source overlap between different leks was not common but did occur at low frequency, providing evidence for long-distance seed dispersal by umbrellabirds into leks. Our findings are consistent with the idea that seed pool diversity within leks may be shaped by the interaction between density of local trees, which can vary considerably between leks, and umbrellabird foraging ecology, particularly a lack of territorial defense of fruiting trees. Taken as a whole, this work adds to our growing appreciation of the ways resource distribution and associated frugivore foraging behaviors mechanistically shape seed dispersal outcomes and the distribution of plant genotypes across the landscape. 相似文献
5.
Campbell RB 《Bulletin of mathematical biology》2007,69(7):2249-2259
This work studies the coalescent (ancestral pedigree, genealogy) of the entire population. The coalescent structure (topology)
is robust, but selection changes the rate of coalescence (the time between branching events). The change in the rate of coalescence
is not uniform, rather the reduction in the time between branching events is greatest when the coalescent is small (immediately
after the common ancestor is the only member of the coalescent) with little change when the coalescent is large (immediately
preceding when that common ancestor becomes fixed and the size of the coalescent is N). This provides that the reduction in the coalescent time due to selection is much greater than the reduction in the cumulative
size of the coalescent (total number of ancestors of the present population after and including the most recent common ancestor)
due to selection. If Ns≫1, the coalescent and fixation times are approximately equal to
, which is much less than the value N which would result from neutral drift (N rather than the canonical haploid neutral fixation time 2N is the appropriate comparison for the model considered here), in particular, it is 70% less for Ns=10 and 95% less for Ns=100. However, for those values of Ns, and N ranging between 103 and 106, the reduction in the cumulative size of the coalescent of the entire population compared to the neutral case ranges from
17% to 65% (depending on the values of N and s). The coalescent time for two individuals for Ns of 10 and 100 is reduced by approximately 70% and 94%, respectively, compared with the neutral case. Because heterozygosity
is proportional to the coalescent time for two individuals and the number of segregating alleles is proportional to the cumulative
size of the coalescent, selection reduces heterozygosity more than it reduces the number of segregating alleles. 相似文献
6.
Lindsey Nielsen Dawn Meehan-Meola Annelisa Kilbourn Acacia Alcivar-Warren 《Conservation Genetics》2008,9(1):239-242
As the population sizes of the black and white rhinoceroses continues to decline, more efforts are needed in multiple areas
to help with the conservation efforts. One area being explored is the use of genetic diversity information to aid conservation
decisions. In this study, we designed 21 microsatellite primers for white and black rhinoceroses, 16 and 17 of which amplified
bands in the white and black rhinoceros, respectively. Out of these primers all 16 were polymorphic in the white rhinoceros
and 12 of the 17 were polymorphic in the black rhinoceros. The mean number of alleles was 3.31 and 2.12, the expected heterozygosities
were 0.420 and 0.372, and the observed heterozygosities were 0.436 and 0.322 for the white and black rhinoceroses, respectively.
Seven of the primers produced different allele sizes and variations that distinguished between black and white rhinoceroses.
Further genetic analyses with larger wild population sample sizes and markers are recommended to obtain a better understanding
of the genetic structure of the black and white rhinoceros populations in order to be useful in the conservation efforts of
these critically endangered species.
A. Kilbourn—In memoriam. 相似文献
7.
We examine the relationship of the inbreeding coefficient (f) and molecular estimates of inbreeding (IR, sMLH) in the Icelandic sheepdog. The breed experienced a severe genetic bottleneck and near extinction in the last century. Molecular
estimates and the inbreeding coefficient are significantly correlated despite the moderate number of markers and individuals
used in this study. This is most likely an effect of the extreme relatedness and relatively high variance in individual inbreeding
coefficients in the population. There is a significant relationship between inbreeding (f) and the occurrence of hip dysplasia. However, the molecular measures did not detect hip dysplasia as an inbreeding effect. 相似文献
8.
Cheng-Yu Hung Yi-Yen Chen Tsai-Wen Hsu Tsurng-Juhn Huang Tzen-Yuh Chiang 《Conservation Genetics》2008,9(5):1337-1339
Suzukia shikikunensis Kudo is an endemic plant in Taiwan and suffers habitat destruction caused by human overexploitation. In this study, we developed
12 microsatellite primer pairs for genetic study. These markers were screened for 24 samples collected from wild populations distributed in Taiwan, and for a sister species
S. luchuensis collected from Yonaguni and Lutao Islands. The number of alleles ranged from 5 to 14. The expected (H
E) and observed (H
O) heterozygosities were 0.65–0.922 and 0–0.625, respectively. All loci were significantly deviated from Hardy–Weinberg equilibrium
due to the heterozygote deficiency. These primers amplifying microsatellites in the two species may provide a useful tool
for population genetics to establish conservation strategy. 相似文献
9.
In this study, we used genetic-based approaches to estimate population size and structure of Eurasian otter along the Drava River in Hungary, and compared these results to traditional survey-based methods. The relative spraint density of otter was estimated based on the number of fresh (Df) and total number (Dt) of spraints collected on standard routes over a 2-year period. Nine microsatellite loci were screened, generating 17 individual otter genotypes composed of 45 different alleles. The expected heterozygosity ranged from 0.53 to 0.89 and observed heterozygosity from 0.25 to 0.92. The mean density (Dg) estimated over six different sites was 0.17 individuals per km of shoreline. A close correlation was found between the number of genotypes and spraint counts along a standard route (fresh spraints: rP=0.85, P<0.01; total spraints rP=0.76, P<0.05). All genotypes found within the 50 km-long study area were closely related (Dm ranged between 0.08 and 0.21). 相似文献
10.
Crespel L Gudin S Meynet J Zhang D 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2002,104(2-3):451-456
Two dihaploid Rosa hybrida L. genotypes, derived through parthenogenesis by using irradiated pollen, were crossed with clonally propagated plants of
the diploid species Rosa rugosa Thunb. and Rosa wichuraiana Crép., respectively. Three progeny groups were obtained which contained numerous polyploids, as determined by flow cytometry.
Production of fertile 2n female gametes is apparently very common in one of these R. hybrida dihaploid derivatives, whereas the other one is able to produce fertile 2n pollen. Hence, an amplified fragment length polymorphism
(AFLP) study was performed on the parental plants and the resulting hybrid offspring in order to estimate (1) the respective
genomic parental contributions, and (2) the level of heterozygosity transmitted by the 2n unreduced gametes. Comparison of
the levels of transmitted parental heterozygosity revealed that two types of 2n gametes were produced simultaneously, presumably
resulting from restitution at the first and at the second meiotic division, respectively.
Received: 15 February 2001 / Accepted: 22 May 2001 相似文献