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1.
Ruiz-Garcia  M.  Campos  H. A.  Alvaréz  D.  Kajon  A.  Diáz  S. 《Russian Journal of Genetics》2002,38(2):165-180
Until the present moment, only a scarce number of Latin American domestic cat populations have been studied from a population genetic standpoint. For this reason, the cat populations of La Havana (Cuba), San José (Costa Rica), Bogotá and Ibagué (Colombia), Asunción (Paraguay), Santiago (Chile) and Buenos Aires (Argentina) were sampled for several coat genes. The results obtained were as follows: (1) there was a strong genetic resemblence between several Hispanic American cat populations (especially, those of Buenos Aires, San José and the two Colombian populations studied) and those from South Western United States (California, Texas and Colorado), which adds suport to the suspicion that these populations probably have a common origin; (2) The cat population of Santiago (Chile), contrarily to the other Hispanic American populations studied, showed a strong genetic resemblance with some Anglo North American populations; and (3) The I (long hair) and d(dilution) alleles showed systematic higher frequencies in the Hispanic American populations than those observed in Spain. Although the Hispanic American populations were not identical to the current Spanish populations (with the exception of Asuncion), this historic genetic experiment was very different to that found for the British populations and their overseas colonies.  相似文献   

2.
Seven Artemia samples from three South American countries (Chile, Brazil, Peru) were studied by starch electrophoresis with the aim of comparing levels of genetic variation and genetic similarity to representative populations of A. franciscana (San Francisco Bay, California, USA) and A. persimilis (Buenos Aires, Argentina), which are species endemic to the New World. Based on the analysis of 22 loci, parameters measuring genetic variability were, for some populations, found to be among the highest reported for Artemia so far. The percentage of polymorphic loci varied from 31.8% (Piura, Peru; Buenos Aires) to 50% (Los Vilos and Salar de Atacama, Chile), while the observed heterozygosity varied from 0.025 (Piura) to 0.165 (Los Vilos, Chile). A dendrogram based on Nei's genetic distance (D) produced four major groups. The Argentinian form, A. persimilis; the San Francisco Bay strain together with samples from Brazil (Macau and Rio Grande do Norte) and Chile (Pichilemu and Salar de Atacama); two coastal populations from Chile (Los Vilos and Iquique) and the sample from Peru (Piura). These four groups have inter-group D values that are, in some cases, far above those normally associated with conspecific populations.  相似文献   

3.
The phenotypes of 295 stray cats seen in the capital area of Buenos Aires, Argentina, between March and December of 1989 were recorded. The corresponding mutant allele frequencies were as follows: O = 0.28, a = 0.83, Ta = 0.01; tb = 0.31; d = 0.45; I = 0.40; S = 0.28; W = 0.02. The allele frequencies calculated at the O locus were consistent with those expected for a randomly breeding population according to the formula for the Hardy-Weinberg equilibrium. The analysis of the genetic distances between Buenos Aires and several European cat populations revealed that the Spanish and, especially, those with a proven more ancestral genetic constitution, are the most closely related. When a similar analysis was carried out, including other Latin American cat populations, those of Spanish origin were found to show the highest degree of relatedness. These findings suggest that the Buenos Aires cat population was not genetically structured following the "two-stepping-stone" model and support the hypothesis that differential gene flows play a transcendental role in understanding the genetic composition of domestic cat populations.  相似文献   

4.
Blood donors (N = 150) at San José Hospital (Santiago, Chile) were typed for one VNTR locus (D1S80) and three STR loci (D18S849, D3S1744, D12S1090). A questionnaire was used to determine the socioeconomic level of the donors, because it is known that some genetic markers (e.g., the ABO and Rh groups) are differentially distributed between different socioeconomic strata. This methodology revealed that two of the three socioeconomic strata distinguishable in Santiago were present in our sample of blood donors, with stratum II representing the middle strata and stratum III the low strata. Allele frequency was determined for each locus and socioeconomic stratum, and it was found that the allele distributions of each locus in socioeconomic strata II and III were statistically similar. All loci conformed to the Hardy-Weinberg law and there was no evidence for association between the alleles of the four loci, allelic frequencies being similar to those found in North American Hispanic populations. The results support the view that the analysis of these loci may have useful applications in population genetics as well as in identity tests.  相似文献   

5.
M. Ruiz Garcia 《Genetica》1990,82(3):209-214
Two Catalan cat populations (Spain) were analyzed. The genetic profiles of these Catalan populations are very homogeneous. The low q (t b) values are the most outstanding factor. These populations and two British cat populations were compared with different colonial settlement cat populations. A close genetic relationship was found between Catalan populations and those of California, Texas, Colorado, Mexico and the North of South America (Caracas and Willemstad (Curaçao)).  相似文献   

6.
In this paper we identify new genetic profiles of eight Latin American cat populations. In addition, we combine data from the present study and previously published data on 70 other American and European populations to discuss (1) the points of introduction of mutant alleles for cat coat phenotypes from Europe into Latin America, (2) the heterozygosity levels at these loci in the current Latin American cat populations, (3) the level of genetic heterogeneity among Latin American cat populations, and how this compares with levels found in North American and European cat populations, and (4) how many different cat gene pools are currently present in Latin America. We also include in our purview historical records of human migrations from Europe to and within the Americas. Our analyses clearly support the view that the current genetic profiles and structuring of cat populations in Latin America can be largely explained by the historical migration patterns of humans. This work is dedicated to the memory of Dr Roy Robinson. May he rest in peace.  相似文献   

7.
Sesarini C  Remis MI 《Genetica》2008,133(3):295-306
Sinipta dalmani is an Argentine grasshopper whose chromosome polymorphisms have been widely studied through cytogenetic, morphometric, and fitness component analyses. The present work analysed molecular and morphometric variation in seven chromosomally differentiated populations from Entre Rios and Buenos Aires provinces to analyse population structure. Molecular studies were performed studying RAPD loci and morphometric analyses were carried out measuring five morphometric traits. Genetic variability was high in all studied populations and was characterized by a decrease in H as a function of latitude and temperature. Both conventional F(ST) analysis and Bayesian approach for dominant marker showed that there were significant genetic differences among all populations, between provinces, and among populations within provinces. Entre Rios populations showed higher mean numbers of migrants per generation as well as low genetic differentiation and high gene flow with almost all populations whereas Buenos Aires populations may be considered as a result of a more recently colonization. There is considerable morphometric variation between populations and this variation correlates with latitude and temperature. Our results suggest that selection contributes to phenotypic differentiation among populations by moulding the differences in trait means whereas genetic drift is responsible for differences in the matrix of variance-covariance. The gene flow detected is insufficient to prevent phenotypic and chromosome divergences.  相似文献   

8.
Aim Two species of the brine shrimp, namely Artemia franciscana Kellogg and A. persimilis Piccinelli and Prosdocimi, inhabit Chile. Most studies so far have shown that A. franciscana is the most widely distributed species in Chile, with A. persimilis present only in Chilean Patagonia. In general, there is good agreement between morphological and genetic comparisons of Chilean populations with respect to species discrimination. However, a number of results indicate an overlap with some populations tending to diverge from A. franciscana and/or resembling A. persimilis. Prior to the mid 90's the use of DNA markers in Artemia was rather limited, despite their successful application in numerous other species. In this study, we investigate whether the conclusions drawn from traditional comparative tools are congruent with the pattern of genetic divergence depicted by DNA analysis at the mitochondrial level. Location Eight sites in Chile and two reference samples of A. franciscana and A. persimilis from San Francisco Bay (USA) and Buenos Aires (Argentina), respectively. Methods Restriction fragment length polymorphism (RFLP) analysis of a 535 bp segment of the mitochondrial 16S rRNA gene with nine restriction enzymes in 240 individuals. Results No haplotype was shared between the two species. Five restriction enzymes produced species‐specific patterns, enabling the unambiguous assignment of populations to species. Very high (100%) bootstrap values supported the clustering of haplotypes in two groups corresponding to the two species. The two species were clearly differentiated with average sequence divergence of 12.3%. High genetic differentiation was also found among con‐specific populations of A. franciscana with an FST estimate of 91%. Main conclusions The mitochondrial DNA (mtDNA) results of this study show a broadly similar pattern to those of previous allozyme and nuclear DNA analyses, with the two New World species appearing as highly divergent. The presence of A. persimilis in southern Chile (Chilean Patagonia) was confirmed. Hence, a species previously regarded as geographically restricted mainly to Argentina, appears to have expanded its range. Populations of A. franciscana appear highly structured with a level of inter‐population genetic differentiation much higher for mtDNA than previously reported with allozymes. Clustering of these populations does not follow a clear geographic pattern. The identification of population‐specific genetic markers for A. persimilis and A. franciscana will help to tackle further aspects of the speciation patterns of these species.  相似文献   

9.
M. Ruiz Garcia 《Genetica》1990,82(3):215-221
New genetic profiles of domestic cat populations were studied in different parts of the Spanish Mediterranean coast. The t b frequency is the most outstanding differentiated factor between the populations analyzed. The low t b frequencies found in Barcelona and other Catalan localities are the most important characteristic of these populations and, probably, find an explanation in the extraordinarily high historical and commercial relationships between Barcelona and the Eastern Mediterranean (Greece, especially) during the 14th and 15th centuries. In other Spanish Mediterranean littoral cities the t b frequencies reach higher values and are more similar to those found in other Western European cat populations. Significant differences found in certain allelic frequencies (Orange and Blotched) caused by the urban-rural effect are discovered between Barcelona and two nearby rural cat populations.  相似文献   

10.
Kholin SK 《Genetika》2012,48(5):655-659
The frequencies of mutant coat color genes have been estimated in the cat populations of five settlements in Primorskii krai, Russia: two cities (Partizansk and Spassk-Dal'nii), a town (Khorol'), and two villages (Dmitrievka and Brovnichi). The genetic profiles of these populations have been found to be relatively homogenous and to correspond of the cat population of the city of Vladivostok studied earlier. No considerable differences in gene frequencies have been found between urban and rural cat populations. The data suggest a common origin of all domestic cat populations of Primorskii krai.  相似文献   

11.
《Anaerobe》1999,5(3-4):209-212
Little is known about the genetic relationship of pathogenic strains of Clostridium difficile from various parts of the world. We used Hind III restriction digestion of whole DNA to type isolates of C. difficile form hospitals in Argentina and Chile. The restriction pattern type of these South American isolates was classified according to the existing REA library of over 400 distinct REA types in over 90 groups, based on typing of more than 6000 clinical isolates. A total of 22 isolates of C. difficile was obtained and typed. The majority of isolates were matched to groups previously seen in North American and Europe. Three toxigenic groups, R, F, and Y, predominated in the isolates. Five isolates were found to be non-toxigenic and three belonged to group M, the most common non-toxigenic group found in North America. Several identical types were recovered from different hospitals, and types of the same group were found in both Buenos Aires and Santiago.  相似文献   

12.
The allelic frequencies of nine Mendelizing genetic characteristics that control coat colour, tabby and length and some skeletal abnormalities have been studied in four feral domestic cat populations, two in the north of Catalonia (Girona and Roses & L’Estartit, northeastern Spain) and two Adriatic Italian populations (Rimini and Venice). Using different genetic and multivariate analyses (Nei’s and Cavalli-Sforza and Edwards’s genetic distances, phenograms and cladograms using different algorithms, strict consensus trees, canonical population, principal coordinates and nonmetric multidimensional scaling analyses), I show the genetic relationships between these populations and other Western European cat populations previously studied. In the Western European area comprising Catalonia, Italy, France and Great Britain, I found significant spatial structure for thet b, l andW alleles and for the average correlogram for the seven alleles studied as a whole using a spatial autocorrelation analysis. The genetic distance matrices between these European cat populations also showed a significant correlation with the geographical distance between these populations using Mantel’s test. These analyses showed that in each of these countries, local cat populations have characteristic genetic profiles which were different to neighbouring populations in nearby countries. At least in this area of Western Europe, the geographical distances between cat populations (although the gene flow can be relatively high) is an important factor which can explain differences in allele frequencies between these populations.  相似文献   

13.
The carnivore community of the altiplano ecosystem of the high Andes, including the Andean mountain cat (Leopardus jacobita) and pampas cat (Leopardus colocolo), is one of the least studied in the world. We determined the origin of 186 carnivore samples (184 faeces and two skulls) collected above 3000 m above sea level in northern Chile, including 33 from the Andean mountain cat and 75 from the pampas cat using diagnostic molecular genetic sequence variation. We determined for the first time food habits, habitat and physiographic associations, and general patterns of molecular genetic variation of the Andean mountain cat and the pampas cat in Chile. Both species had narrow dietary niches dominated by small rodents and there was a wide overlap in diet composition (0.82), suggesting low levels of prey partitioning between species. The mountain viscacha (Lagidium viscacia) made up a large proportion of the biomass of the diet of both species, especially for the Andean mountain cat (93.9% vs. 74.8% for the pampas cat), underscoring the importance of further research and conservation focus on this vanishing prey species. Although the probability of finding Andean mountain cat scats increased with altitude and slope, there was substantial geographical overlap in distribution between species, revealing that the pampas cat distribution includes high-altitude grassland habitats. The Andean mountain cat had relatively low levels of mitochondrial DNA (mtDNA) genetic variation (two mtDNA haplotypes) compared with the pampas cat (17 mtDNA haplotypes), suggestive of a distinct evolutionary history and relatively smaller historic populations. These insights will facilitate and provide tools and hypotheses for much-needed research and conservation efforts on these species and this ecosystem.  相似文献   

14.
Although mitochondrial DNA mapping of Varroa destructor revealed the presence of several haplotypes, only two of them (Korean and Japanese haplotypes) were capable to infest Apis mellifera populations. Even though the Korean haplotype is the only one that has been reported in Argentina, these conclusions were based on mites sampled in apiaries from a specific geographical place (Buenos Aires province). To study mites from several sites of Argentina could reveal the presence of the Japanese genotype, especially considering sites near to Brazil, where Japanese haplotype was already detected. The aim of this work was to study the genetic structure of V. destructor populations from apiaries located in various provinces of Argentina, in order to determine the presence of different haplotypes. The study was carried out between January 2006 and December 2009. Phoretic adult Varroa mites were collected from honey bee workers sampled from colonies of A. mellifera located in Entre Ríos, Buenos Aires, Corrientes, Río Negro, Santa Cruz and Neuquén provinces. Twenty female mites from each sampling site were used to carry out the genetic analysis. For DNA extraction a nondestructive method was used. DNA sequences were compared to Korean haplotype (AF106899) and Japanese haplotype (AF106897). All DNA sequences obtained from mite populations sampled in Argentina, share 98% of similitude with Korean Haplotype (AF106899). Taking into account these results, we are able to conclude that Korean haplotype is cosmopolite in Argentina.  相似文献   

15.
We conducted surveys of mutant allele frequencies of four cat populations in Arkansas and Tennessee during 2002. Our calculations and analyses support that Southwestern cat populations were relatively more genetically similar to each other than compared to cat populations in other areas of North America. However, the cat population of Fort Smith is slightly different from the other cat populations studied in the Southwestern United States. Although there is a clear significant spatial geographic pattern for many mutant coat allele frequencies in the United States and Canada cat populations (d, l, S, and W), our results revealed that there is not a significant isolation-by-distance model affecting these cat populations. Our data also support the historical migration hypothesis because our calculated allele frequencies were genetically similar to cat populations located in ancestral areas of Europe. Different phenograms, including new European cat genetic profiles, showed that the Southwestern cat populations studied are of a clear British origin. Therefore, migration routes of early Arkansas and Tennessee settlers help explain the similarities of allele frequencies among domestic cat populations.  相似文献   

16.
Aequipecten techuelchus is an endemic scallop of the Argentine biogeographic province in the southwest Atlantic Ocean which supports a commercial fishery that has presented strong fluctuations since the 1960s. It is unclear if distinct localities constitute a single panmictic population. We used next-generation sequencing to obtain microsatellite loci that could be used to evaluate genetic diversity and differentiation among populations. We developed 30 polymorphic microsatellite loci, of which 13 meet the standard criteria required for population genetic analyses, including Hardy-Weinberg equilibrium, not being linked and with a low frequency of null alleles. The described microsatellite loci were used to estimate relatedness and effective population size, and to test for recent and historic population bottlenecks. Our results suggest that the population of the Tehuelche scallop from San Román, Gulf of San José, Patagonia shows a relatively large effective population size, high levels of genetic polymorphism, low levels of inbreeding and no signs of recent or historic drastic population reductions. These preliminary results should be confirmed with larger sample sizes and the inclusion of other nearby populations.  相似文献   

17.
To determine mutant allele frequencies, surveys of coat phenotypes of the domestic cat (Felis catus L.) were conducted from October 1982 to June 1985 in 23 urban and rural populations of Poland (N = 67-278). The seven gene loci studied included: sex-linked orange (O), agouti (A), tabby (T), full-color expression (D), long hair (L), piebald spotting (S), and dominant white (W). The mutant allele frequencies at these loci are: p(O) = 0-0.139, q(a) = 0.487-0.774, p(Ta) = 0, q(tb) = 0.132-0.451, q(d) = 0-0.332, q(l) = 0-0.220, p(S) = 0.242-0.620, and p(W) = 0. The coefficients of darkness estimated ranged from 0.51 to 0.75, showing no statistically significant differences between urban and rural populations. Of the gene loci studied, only A and S show such differences, with the incidence of alleles a and S being, respectively, significantly higher and lower for urban areas. The relatively great amount of genetic heterogeneity in the cat populations of Poland seems to reflect historical determinants. The Polish data are compared to those from Europe, northern Africa, and western Asia, and geographic patterns in distribution for all of the mutant alleles studied are described.  相似文献   

18.
Objective: To describe subjective oral health status and its association with overall health conditions and socioeconomic factors in the elderly (60 years and older) living in the capital cities with the oldest average populations in South America. Background: Oral diseases are a public health problem, frequently neglected in older adults. In recent years, the subjective assessment of psychological and social consequences of the problems related to oral health has been valued. One of the instruments used to estimate the Oral Health‐Quality of Life is the Geriatric Oral Health Assessment (GOHAI). Material and methods: Representative samples from SABE study (1999–2000) of Santiago (n = 1301), Buenos Aires (n = 1043), and Montevideo (n = 1450) aged 60 and over community‐dwelling people. We assessed OH‐QoL (GOHAI), self‐reported missing teeth, denture use, and self‐rated‐health, among other indicators. Logistic regression models(GOHAI < 58) for each city, adjusted by sex and age, were applied. Results: GOHAI average scores were higher in Montevideo (54.8 ± 6.1) than in Buenos Aires (53.1 ± 7.4) and Santiago (49.9 ± 8.6). A pronounced gradient of the oral condition and GOHAI scores were observed within the three‐cities. Denture use ‐less prevalent in Santiago and more common among women‐ is a protective factor against a poor OH‐QoL. Conclusion: Socioeconomic inequalities in oral health status and OH‐QoL are observed in the three cities. The increasing life expectancy emphasizes the need to integrate prevention and treatment efforts, as a way to improve OH‐QoL over the course of a lifetime.  相似文献   

19.
Despite the institution of multicultural policies and pluriethnic governments across Latin America, racist violence against Indigenous and Afro-descendant groups persists. Yet the racial facets of violence against non-ethnic campesinos remain unexplored. Integrating scholarship on race as a global structure and Latin American racial formations, I offer an account of racialization in Colombia. This article analyzes the racial dynamics of resistance to extractivism in Colombia's Campesino University, uniting Indigenous and campesino groups like the San José de Apartadó Peace Community. While the dominant race lexicon separates “campesinos” like San José's peasants from “Indigenous” and “Black” groups, I argue that the identifier campesino mestizo hides how San José's farmers were “de-indigenized” yet remain racialized as the less-than-human “Indigenous savage”. If racialization works to dominate but also divide the subaltern, then Campesino University participants’ cross-ethnic solidarity network against what they affirm is a shared experience of racist violence both unveils and counters racism.  相似文献   

20.
Two hundred seventeen male subjects from Costa Rica, Mexico, and the Hispanic population of the southwestern United States were studied. Twelve Y-chromosome STRs and the HVSI sequence of the mtDNA were analyzed to describe their genetic structure and to compare maternal and paternal lineages. All subjects are part of two NIMH-funded studies to localize schizophrenia susceptibility genes in Hispanic populations of Mexican and Central American ancestry. We showed that these three populations are similar in their internal genetic characteristics, as revealed by analyses of mtDNA and Y-chromosome STR diversity. These populations are related through their maternal lineage in a stronger way than through their paternal lineage, because a higher number of shared haplotypes and polymorphisms are seen in the mtDNA (compared to Y-chromosome STRs). These results provide evidence of previous contact between the three populations and shared histories. An analysis of molecular variance revealed no genetic differentiation for the mtDNA for the three populations, but differentiation was detected in the Y-chromosome STRs. Genetic distance analysis showed that the three populations are closely related, probably as a result of migration between close neighbors, as indicated by shared haplotypes and their demographic histories. This relationship could be an important common feature for genetic studies in Latin American and Hispanic populations.  相似文献   

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