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1.
Eight wild populations of the High Sierra golden trout, Salmo aguabonita, and one domestic stock of rainbow trout, Salmo gairdneri, were examined for biochemical-genetic variation in eight protein systems. Variation within the eight systems was determined by at least 10 loci in both golden and rainbow trout and all the alleles identified in rainbow trout were observed as electro-phoretically identical phenotypes in golden trout. Variation was observed at an average of 51 percent of the loci in the golden trout samples and for five of the 10 loci in the rainbow trout. Average heterozygosity ranged from 12.6 to 13.9 percent for seven of the golden trout populations with one showing a low value of 5.4 percent. A comparable estimate of 12.1 percent was found for the rainbow stock. On the basis of genetic variation and allele frequencies at three loci, the eight golden trout populations were divided into two distinct groups. Three populations sampled from the Little Kern River basin tended to be genetically distinct from two additional Little Kern River basin populations and from three geographically distinct populations sampled from the eastern Kern River area. The former three populations were hypothesized to be of a recent rainbow-golden hybrid origin. Trout in the other two Little Kern River basin populations, sampled in head-waters of a stream tributary to the Little Kern River, were considered to be the threatened Little Kern golden trout, S. a. whitei Evermann, due to their high degree of genetic similarity to the geographically distinct subspecies S. a. aguabonita sampled from the eastern Kern River area. The finding of substantial genetic variation in the wild golden trout populations indicates that this threatened species is not at present genetically impoverished and thus does not appear to be in immediate danger of extinction through lack of adaptive capability.  相似文献   

2.
A series of 1,187 blood samples from eight population groups in the Eastern Highlands of Papua New Guinea were tested for genetic variation in blood groups, serum proteins and red cell enzyme systems. The populations belonged to the language groups Gahuku-Asarc-Bena Bena, Kamano, Yagaria, Keiagana, Fore, Agarabe, Auyana and Tairora. Polymorphic variation was found in the ABO, MNS, P1, Rh, Hp, Tf, SEP, 6-PGD, ADA, MDH, and PGM genetic systems. East to West variation was shown in the language groups; the O, S, R2, and R0 genes increase in frequency from East to West and the A, R1, and M genes decrease in the same direction. In the East higher frequencies were found for the Du antigen, for the PGM21 gene and for a PGM second locus variant. The MDH 3 variant was found in all the populations, its highest value being in the Tairora.  相似文献   

3.
Red cell samples from persons belonging to four Amerindian linguistic groups in Colombia were investigated for genetic variants in eight blood group systems: for three of the groups investigations were extended to ten red cell enzyme and four serum protein systems. The groups studied are the Noanama (including six Empera) of the Rio Siquirisua and Rio Docampado on the Pacific lowlands and the Cofan, Ingano and Siona Indians of the Upper Rio Putumayo and its tributaries to the east of the Andes. Only blood group O was present among two of the groups and the same groups were 100% Kp(b +), k in the Kell system. Di(a +) frequencies were high in three groups and there was marked variation between groups for the MNS, Rh, P, Lewis and Duffy systems. Polymorphism in all the three linguistic groups studied for serum proteins and red cell enzymes was present only in the red cell acid phosphatase, phosphoglucomutase (locus-1) and haptoglobin systems. 6-phosphogluconate dehydrogenase was polymorphic in the Noanama, and caeruloplasmin was polymorphic in the Ingano linguistic group. In addition two persons belonging to the Cofan linguistic group revealed the presence of an “atypical” component in the lactate dehydrogenase system. No variation was found in the other six red cell enzyme and two serum protein systems. Comparison with published data on red cell enzyme and serum protein groups for other South American Amerindian populations shows the Colombian populations studied here most closely resemble the Cayapo of Brazil.  相似文献   

4.
珊瑚菜居群遗传多样性的SRAP分析   总被引:1,自引:0,他引:1  
利用SRAP对伞形科单种属珊瑚菜7个野生居群和1个栽培居群进行了研究。结果表明:共筛选出8个引物组合,在珊瑚菜8个居群中共扩增出168条条带,其中多态性条带为118条,多态性比率为70.23%;平均每对引物扩增的多态性条带为14.75。各居群之间珊瑚菜遗传相似性系数范围为0.8306~0.9836,遗传距离范围为0.0165~0.1856。聚类分析表明,以相似性系数大于0.8并结合地理分布来看,所研究的野生珊瑚菜居群可以大体分为3类,辽宁大连的野生居群为一类,山东威海—山东青岛的居群为一类,而山东日照—广州深圳之间的为一类。  相似文献   

5.
Nine Carib and eight Tupi groups were studied for a minimum of eight common polymorphic systems and compared in terms of genetic distances using the methods of Nei and Edwards. Two levels of genetic information were distinguished, one with a maximum of 20 loci and another with a maximum of 12 loci considered. The dendrograms produced consistent, reproducible results, independent of the method used, when a minimum of ten polymorphic systems were included in the analysis. Irrespective of the number of systems or the method used, the Tupi showed two to three times higher average interpopulation genetic distances than the Carib groups, which may be due to their lower average population sizes, allowing for the action of genetic drift and/or founder effects, as these two sets of populations do not differ significantly in geographic range, years of contact with non-Indians, or degree of acculturation.  相似文献   

6.
Bemisia tabaci (Hemiptera: Aleyrodidae) is a haplo‐diploid species with a global distribution demonstrating strong geographical structure with eight recognizable genetic groups. Fifteen microsatellite loci (335 alleles, 6–44 alleles per locus) were derived from four of the eight groups and were then screened across 33 populations. These loci clearly differentiate the populations. The microsatellites amplified best in individuals from genetic groups rep‐resenting the Mediterranean, Middle East, Asia (three groups) and Australasia/Oceania and amplified less well with populations from sub‐Saharan Africa and the New World. This differential amplification pattern is a direct result of the relatedness to the microsatellite source material.  相似文献   

7.
The variations of blood groups and biochemical polymorphisms in the populations of the two miniature pig strains reared in Japan were investigated in this report. The variations in eight blood group systems were investigated by using serological techniques, and five serum protein systems by using starch gel electrophoresis. The Pitman-Moore strain showed no variations in K, O, Tf, Cp and Am systems, but showed plymorphisms in A, E, F, G, H, L, Pa and Hpx systems. The Ohmini strain showed no or little variations in E, F, G, Tf, Pa and Cp systems, but showed polymorphisms in A, H, K, L, O, Hpx and Am systems. From the results of investigation of genetic similarities among nine pig populations including various breeds, it was made clear that the two miniature pig strains were very different genetically, and the Pitman-Moore strain was genetically closer to European large pig breeds than to East Asian native pigs, while the Ohmini strain was close to Thai and Philippine natives.  相似文献   

8.
Within a study of the genetics of Balkan populations, four DNA-STR systems and 19 classical markers were examined in seven samples: Romanians (two groups), Albanians, Greeks and Aromuns (three groups). The results for the DNA-STR systems have been compared with data from the literature. The results show four clear separated groups: sub-Saharan black populations, North-African, Japanese and European populations. The large Balkan populations, except the Greek sample, are genetically more homogenous than the Aromun populations. A second Neighbor-joining tree based on all 23 analyzed systems, show a particular trend of the Aromun groups, which indicates a particular genetic structure.  相似文献   

9.
J. S. F. Barker 《Genetica》1994,92(3):165-175
Sequential electrophoresis, using three different buffer systems on cellulose acetate gels, was used to characterize the allelic variation for esterase-2 in two populations of D. buzzatii in Australia that are separated by 550 km. Twenty-five alleles were detected, of which nine were unique to one population, eight unique to the other, and only eight were common to both populations. Allele frequencies within each population were significantly different between the two major chromosome sequences (standard and j inversion), and for each chromosome sequence allele frequencies were significantly different between populations. Observed allelic frequency distributions were not significantly different from those predicted for selective neutrality using the homozygosity test statistic. However, estimates of the effective sizes of the populations derived from their observed differentiation, together with the history of the species in Australia, provide support for some form of balancing selection affecting at least some of the alleles.  相似文献   

10.
This study used polymerase chain reaction (PCR) and dideoxy direct sequencing methods to analyze the genetic structure of the chukar partridge (Alectoris chukar) in the Longdong Loess Plateau, northwestern China. A total of 491 nucleotides of mitochondrial DNA from the control region gene were sequenced for 78 chukar partridges from eight different populations. The 24 variable positions defined 25 haplotypes. The high gene flow (Nm=3.75) implied little genetic differentiation between the eight populations. All the populations shared the haplotype C1, which suggested that they all came from a common ancestor. The 25 haplotypes were spread through the populations, but could be clustered into two groups. The haplotype similar index between the two groups was only 0.15, with a genetic distance of 0.43%. The genetic variation was significantly different between the two groups, which had been isolated for all of recorded history. The genetic structure of chukar partridge populations in the Plateau appears to be the result of the synergistic effect of a glacier, along with debris flow and human activities since the middle of the Pleistocene.Communicated by F. Bairlein  相似文献   

11.
入侵植物薇甘菊种群的遗传分化   总被引:5,自引:0,他引:5       下载免费PDF全文
利用简单重复序列区间(Inter simple sequence repeat, ISSR)分子标记技术分析了入侵植物薇甘菊(Mikania micrantha)8个种群的遗传多样性及遗传分化。12个引物共扩增出171个位点,其中多态位点有103个,多态位点百分率(P%)为60.23%,Shannon信息指数(I)为0.281 8,Nei指数(h)为0.184 9,薇甘菊在物种水平具有较高的遗传多样性。AMOVA显示薇甘菊具有较高的遗传分化,36.49%的变异发生在种群间,63.51%的变异发生于种群内,基因分化系数(GST)为0.352 4。种群间的基因流较高,为0.918 7。薇甘菊8个种群之间的遗传相似性很高,平均为0.915 5;遗传距离很小,平均为0.088 4。采用UPGMA法对8个种群进行聚类,可以将8个种群分为两大类群,即内伶仃岛为一个类群,而深圳与东莞内陆种群组成另一类群。薇甘菊现有遗传结构的形成与其生活史特性及入侵生态学特性有关。  相似文献   

12.
The genus Bidens (Asteraceae) has undergone extensive adaptive radiation on the Hawaiian Islands. The 19 species and eight subspecies endemic to Hawaii exhibit much more morphological and ecological differentiation than the continental members of the genus. However, the Hawaiian taxa have the same chromosome number and retain the capacity to interbreed in all possible combinations. Twenty-two populations of 15 Hawaiian taxa and four populations of American taxa were compared at 21 loci controlling eight enzyme systems. Populations of Hawaiian taxa are highly polymorphic. However, little genetic differentiation has occurred among taxa in spite of the high levels of genetic variability. Genetic identities calculated for pairs of populations show that populations of the same taxon are genetically more similar than are populations belonging to different taxa, but all values are high. The level of genetic differentiation that has occurred among the species of Hawaiian Bidens is comparable to the level of genetic differences found among populations within single continental plant species. Moreover, there is no correlation between the isozyme data and morphological data. No groups of taxa are evident in the genetic data, although morphological groups exist. Genetic differentiation at isozyme loci has not occurred at the same rate as the acquisition of presumably adaptive morphological and ecological characters in Hawaiian Bidens. Adaptive radiation may be limited to a few genes controlling morphological and ecological characters.  相似文献   

13.
Pickling cucumbers stored at five temperatures and four relative humidities were examined for growth of eight microbial groups, the activities of two enzyme systems (pectinolytic and cellulolytic), and weight loss. Twenty-four storage tests for 6 days each were conducted during the 2-year study. In general, microbial populations of the eight groups increased rapidly at the higher temperature (>21 C) and humidity (>70%) treatments. Moisture loss of the cucumbers was rapid with combinations of high temperatures and low humidities. The results suggest that the best environmental conditions for storage or transport of cucumbers would be a combination of low temperature (10 C) with high relative humidity (about 95%). These conditions minimized undesirable microbial, enzymatic, and physical changes of stored, pickling cucumbers.  相似文献   

14.
The distribution of genetic markers of blood groups (ABO, Rhesus, MNSs, P, Duffy, Kell-Cellano), plasma proteins (Hp, Gc, Tf, C'3) and red-cell enzymes (AcP, EstD, GLO-1), and also ABH secretion among 10 populations of Western Georgia has been studied. The common characteristic of distribution of gene frequencies for the markers studied was obtained as a whole in Georgia. The Georgians were compared for these markers with some populations of the Caucasus, Europe and West Asia. Among Caucasian populations, Georgians are most similar to Abkhasians. According to some systems, Georgians are close to European groups (ABO, Dubby, GLO-1, EstD), while they are similar to West-Asian groups, as judged by other systems (ABH secretion, AcP). According to Rhesus and MNSs systems, Georgians differ both from populations of Europe and from populations of West Asia.  相似文献   

15.
The genetic polymorphism of eight red cell antigenic systems was examined in two population samples from Cantabria (north Spain). No significant differences were found between the autochthonous and the resident populations. The results obtained are compared with those for other populations in the north of Spain. The low frequency of the B allele of the AB0 system and the high frequency of the 'cde' haplotype of the Rh system in the Cantabrain and Asturian population suggests that the anthropological characteristics of these two systems, which hitherto have been attributed to the Basques, also apply to the western neighbouring regions.  相似文献   

16.
The isozymes of nine enzyme systems were screened and the frequencies of the flavone glycosylating genes were determined in an outdoor experiment with 70 populations of European S. pratensis and an indoor experiment with 30 populations of the same species. Cluster analysis (using Ward's cluster criterion) were performed on all data sets. In the outdoor experiment, cluster analysis of the flavonoid data gave the same pattern that we obtained in an ealier survey of a larger set of populations and showed clearly that there are eight chemical races in European S. pratensis. No comparable geographic distributiion could be found in the isozyme data set, although the dendrogram showed two very clearly separated groups. The two groups represented the two years in which the populations were grown. This result indicates that isozyme variation in European S. pratensis is largely determined by environmental factors. Observations on changes in isozyme patterns during ontogeny and on differences between indoor and outdoor grown plants of the same F2 crosses confirm this. Differences in isozyme patterns can be caused by very small differencs in environment as is shown by the results of the indoor experiment, in which a slight gradient in environmental conditions was present in the greenhouses. The cluster analysis of the isozyme data from the indoor experiment revealed three distinct groups of populations that could be related to location within the greenhouses. As in the outdoor experiment, the dendrogram for the flavonoids gave the same geographic pattern as found with the earlier survey.  相似文献   

17.
Using horizontal starch gel electrophoresis, ten enzyme systems were surveyed in ten populations of Tetramesa reared from eight species of grass collected from different sites in Britain. Eight species of Tetramesa were recognized on the basis of the number and relative mobilities of electromorph bands for larvae, pupae and adults. No differences were found between populations of T. hyalipennis (Walk.) reared from Elymus repens (L.) and E.farctus (Viv.) or between populations of T. eximia (Gir.) reared from Calamagrostis epigejos (L.) Roth and Ammophila arenaria (L.) Link. Experiments on mate-choice and host preference also supported the electrophoretic results for populations of T. hyalipennis and T. eximia.  相似文献   

18.
利用ISSR标记,对来源于中国7个省(市)的44个扁蓿豆居群的亲缘关系进行了分析。从80条ISSR引物中筛选出多态性强、重复性好的16条引物,对44个扁蓿豆居群基因组DNA进行扩增,共扩增出133条谱带,平均每个引物扩增出8.31条带,其中多态性带115条,多态性位点百分率为87.08%。扁蓿豆种质间遗传相似系数变化范围在0.436~0.908之间。利用UPGMA聚类分析,44个扁蓿豆居群被划分为8个类群,与地理来源有较高的相关性。  相似文献   

19.
Viola odorata has been cultivated for cosmetics and medicine in Europe since antiquity. The spread by humans has expanded its distribution considerably beyond its original range in parts of the Mediterranean region, south‐western Europe, and western Asia. One hundred and sixty‐five plants of V. odorata from 52 collection sites from throughout most of its native range were analysed for seven isoenzyme systems. Twenty‐eight allozymic markers were obtained, twenty‐five of which were geographically variable. A profound east–west differentiation separating Anatolian and Caucasian populations from European populations was detected, with Greek and Sicilian populations somewhat intermediate. Western European populations were rather homogeneous, suggesting a common origin, which also included the Canarian var. maderensis and the naturalized Scandinavian (and British?) populations. Cretan and Cypriot populations were apparently recruited from more westward stations. The possibility that the two allozymic groups of V. odorata reflect isolated Pleistocene refugia is discussed. V. odorata appears to possess more geographically structured variation than has been found in other cultivated and human‐spread species in southern Europe. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society, 2006, 151 , 563–571.  相似文献   

20.
BACKGROUND Congenital malformations (CMs) are a leading cause of infant disability. Geophysical patterns such as 2-year, yearly, half-year, 3-month, and lunar cycles regulate much of the temporal biology of all life on Earth and may affect birth and birth outcomes in humans. Therefore, the aim of this study was to evaluate and compare trends and periodicity in total births and CM conceptions in two Israeli populations. METHODS Poisson nonlinear models (polynomial) were applied to study and compare trends and geophysical periodicity cycles of weekly births and weekly prevalence rate of CM (CMPR), in a time-series design of conception date within and between Jews and Muslims. The population included all live births and stillbirths (n = 823,966) and CM (three anatomic systems, eight CM groups [n = 2193]) in Israel during 2000 to 2006. Data were obtained from the Ministry of Health. RESULTS We describe the trend and periodicity cycles for total birth conceptions. Of eight groups of CM, periodicity cycles were statistically significant in four CM groups for either Jews or Muslims. Lunar month and biennial periodicity cycles not previously investigated in the literature were found to be statistically significant. Biennial cycle was significant in total births (Jews and Muslims) and syndactyly (Muslims), whereas lunar month cycle was significant in total births (Muslims) and atresia of small intestine (Jews). CONCLUSION We encourage others to use the method we describe as an important tool to investigate the effects of different geophysical cycles on human health and pregnancy outcomes, especially CM, and to compare between populations.  相似文献   

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