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1.
In order to investigate the polymorphism of α-globin chain of hemoglobin amongst caprines, the linked Iα and IIα globin genes of Barbary sheep (Ammotragus lervia), goat (Capra hircus), European mouflon (Ovis aries musimon), and Cyprus mouflon (Ovis aries ophion) were completely sequenced, including the 5′ and 3′ untranslated regions. European and Cyprus mouflons, which do not show polymorphic α globin chains, had almost identical α globin genes, whereas Barbary sheep exhibit two different chains encoded by two nonallelic genes. Four different α genes were observed and sequenced in goat, validating previous observations of the existence of allelic and nonallelic polymorphism. As in other vertebrates, interchromosomal gene conversion appears to be responsible for such polymorphism. Evaluation of nucleotide sequences at the level of molecular evolution of the Iα-globin gene family in the caprine taxa suggests a closer relationship between the genus Ammotragus and Capra. Molecular clock estimates suggest sheep-mouflon, goat-aoudad, and ancestor-caprine divergences of 2.8, 5.7, and 7.1 MYBP, respectively.  相似文献   

2.
We have determined the apparent and actual spontaneous mutation frequencies and rates for different species and strains of the thermoacidophilic crenarchaeote Sulfolobus. The proportion of mutations caused by insertion sequences has also been analyzed. Mutation frequencies for S. islandicus (0.08–0.6 mutations per cell division and 107 cells) were below those determined for S. solfataricus and comparable to or lower than those for S. acidocaldarius. The proportion of insertion sequence mutations for the S. islandicus strains REN1H1 (9 out of 230) and HVE10/4 (0 out of 24) was found to be considerably lower than in S. solfataricus P1 and P2 and also low in comparison to other S. islandicus strains. Mutants defective in either the pyrEF genes or the lacS gene have been isolated. Their growth phenotype on selective and non-selective medium was examined and the inactivating mutations in either of the genes were determined. In addition the reversion frequencies for these mutants were measured and found to be in the range of <0.6–1.5 mutations per cell division and 108 cells. However, when being subjected to electroporation as a transformation procedure, increased reversion was observed.  相似文献   

3.
Blood samples were procured from the following populations of putatively pure Indians in Bolivia: 503 Aymará from the Altiplano and Yungas, 30 Chama, 11 Tacana, 14 Chácobo, 109 Itonama, 67 Moré, and 27 Sirionó from the Beni and lowland rainforest. Erythrocytes from these 761 specimens were tested for antigens in the A-B-O, M-N-S-s, P, Rh-Hr, Lutheran, Kell-Cellano, Lewis, Duffy, Kidd, and Diego systems, and for the Wright agglutinogen. The serum samples were tested for haptoglobins and transferrins; and hemolysates were prepared and examined for hemoglobin types. Results of these tests are presented as phenotypes and calculated gene frequencies on appropriate tables. A map is included to show the locations of the populations from which blood samples were obtained. Frequencies are generally high for the O gene, it being the only gene of the ABO system which appears in the Chama, Chácobo and Sirionó. The presence of A1, A2 or B genes in the Bolivian Indians is interpreted as being most probably of caucasoid introduction. Excepting the Sirionó the frequencies are high for M and low for N genes as is usual for Amerinds, the M gene being the only one detected in the Chama. The s gene frequency in high and the S low except in the small isolated Chácobo population in which S gene frequency is extremely high for Amerinds. Inbreeding and perhaps genetic drift in this small isolate may account for this aberrancy from normal. The Bolivian specimens presented the high frequencies for genes R1 (CDe) and R2 (cDE) and the low frequencies for genes r (cde) and R0 (cDe) usually observed in American Indians. The Lua factor was observed in only one of 120 Aymará at Santa Fe in the Yungas. The Lua factor, when observed in Amerinds, suggests foreign introduction of the responsible gene. Fya gene frequencies are consistently high and excepting the Aymará and Chama so also are Jka frequencies. Frequencies for the Diego (Dia) factor vary from 3.70% in 27 Sirionó to 73.33% in 30 Chama. No K, Mia, Vw or Wra antigens were demonstrable in the Indian blood samples from Bolivia. Phenotypes and calculated gene frequencies for haptoglobins and transferrins are presented. All Bolivian Indian bloods tested electrophoretically contained only hemoglobin (A) as a major component.  相似文献   

4.
Summary Glucose phosphate isomerase (E.C. 5.3.1.9) and phosphoglucomutase (E.C. 2.7.5.1) were found to be polymorphic in a laboratory colony of Aedes albopictus. The glucose phosphate isomerase locus is represented by two alleles resulting in three genotypes, while the phosphoglucomutase locus is represented by at least five alleles giving rise to a total of 15 genotypes. The inheritance of these two enzymes is of the Mendelian type with codominant alleles. Present data indicate that these genes are not linked.Of 105 mosquitoes analysed for these two gene-enzyme systems, the frequencies for glucose phosphate isomerase alleles are Gpi S=0.68 and Gpi F=0.32, while the frequencies for phosphoglucomutase alleles are Pgm A=0.16, Pgm B=0.11, Pgm C=0.19, Pgm D=0.30 and Pgm F= 0.24. The frequencies of the three glucose phosphate isomerase genotypes are in accord with Hardy-Weinberg expectations (X 1 2 =2.74). Similarly, the frequencies of the 15 phosphoglucomutase genotypes probably do not differ significantly from Hardy-Weinberg expectations (X 10 2 = 18.45).  相似文献   

5.
This paper reports haptoglobin testing of 2,029 serum specimens and transferrin typing of 1,911 specimens obtained from villages representing a wide range of environments and cultures in the Markham River Valley region of northeast New Guinea. The haptoglobin gene frequencies ranged from 90.0% to 61.4% for Hp1 and the frequency of the transferring gene Tfc ranged from 94.9% to 71.5%. Other transferrin genes present were TfD1 and, in low frequency, TfB Lae. Overall, no apparent correlations were found between the frequencies of these genes and altitudes, languages or distances of the villages studied up the valley. It was felt that the arguments put forward earlier emphasizing the role of genetic drift in determining gene distribution in New Guinea could be also applied to explain the distribution of the haptoglobin and transferrin genes in the Markham River Valley.  相似文献   

6.
Segregation Distorter (SD) associated with the second chromosome of D. melanogaster is found in nature at equilibrium frequencies lower than 5%. We report extremely high frequencies of SD (30–50%) in two selected strains, established in 1976, and show it to be responsible for the accumulation of deleterious genes in chromosome II. Samples of chromosomes extracted over a 4-year period were characterized with respect to distortion, sensitivity, lethality, sterility, and inversions. SD chromosomes were inversion-free as they have been shown to be in the Mediterranean area. The cosmopolitan inversion In(2L)t was found associated with SD + chromosomes. Lines polymorphic for SD have accumulated linked lethal and female-sterile genes approaching a near balanced system. It is proposed that deleterious genes linked in coupling to SD were accumulated by the balancing effect of distortion, while drift and restricted recombination account for the accumulation of deleterious genes linked in repulsion by a mechanism similar to Muller's ratchet. Our results should not be viewed as a particular case as SD chromosomes associated with detrimental genes and inversions are present in almost all populations around the world. The system could evolve in the way we describe whenever equilibrium conditions are broken down in small populations and lead to an increase in SD frequency.  相似文献   

7.
For the first time, microsatellite loci were used to study the genetic structure in Alectoris chukar cypriotes. Four of the ten tested microsatellite loci were found to be polymorphic in 33 individuals from four regions of Cyprus. The differentiation test between all the pairs of samples gave non-differentiation exact P values in every case (P>0.05). The posterior probability distribution on the number of source populations indicated only one population (P=0.977); also, a high Bayes factor value (130.020) was obtained. Posterior co-assignment probabilities (measures of similarity) for all pairs of individuals ranged from 0.984 to 1. The global FIS value was not found to be significant. A recent bottleneck of the Cypriot total partridge population is suggested and this is supported by a significant Wilcoxon test (P=0.031) under the Infinite Alleles Model (IAM) and shifted mode in the alleles frequencies distribution. The results suggest that all the individuals studied belong to only one randomly mating (panmictic) population, with low genetic variation and evidence of recent effective population size reduction (genetic bottleneck). A big hunting pressure exists on the island and about 200,000 captive-bred birds are released every year; these individuals are descendant from a small number of eggs collected in a small area of Cyprus in 1986 and this founder effect could explain the existence of a bottleneck and the low genetic variability.  相似文献   

8.
Summary The authors studied the phenotypic distribution of -L-fucosidase in a random sample of the population of the area of Rennes (France). The frequencies of Fu 1 (0.64) and Fu 2 (0.36) genes are significantly different from the frequencies observed in New York whites and blacks.  相似文献   

9.
Summary Simultaneous subtyping of two genetic markers—group-specific component (Gc) and transferrin (Tf)—by electrofocusing enabled us to compute the following gene frequencies for the Tunisian population: Gc IS .0.525; Gc IF , 0.260; Gc 2, 0.215; Tf CI , 0.770; Tf C2 , 0.215; Tf D1 , 0.015.The frequencies of Tf D , Tf C2 , and Gc 1 are higher than those found in Caucasoid populations and can be explained by Negroid contribution. A selective advantage related to the metabolic role of this vitamin D-binding protein does not seem very likely for any particular Gc type or subtype. It is postulated that the differences in the frequencies of the Gc alleles might be related to selective advantage for genes belonging to other genetic systems originally closely linked to either Gc 1 or to Gc 2 alleles.This work was supported in part by the Faculté de Pharmacie et de Médecine Dentaire of Monastir and by a grant from the Ambassade de France in Tunisia  相似文献   

10.
Summary Genetic polymorphism of uropepsinogen group A (PGA) was characterized in human urine using a technique involving both polyacrylamide gel isoelectric focusing and immunoblotting with an anti-PGA antibody. PGA was clearly separable into five fractions, termed I to V in order of decreasing anodal mobility. The most slowly migrating fraction V was composed of F (fast) and/or S (slow) band(s). The population frequencies of the three patterns of fraction V (F, FS, and S) and family studies indicated that PGA V is controlled by a pair of alleles, PGA V * F and PGA V * S, at a single autosomal locus, and that both are codominant. The frequencies of the genes are 0.07 for PGA V * F and 0.93 for PGA V * S.  相似文献   

11.
Abstract A comprehensive study on the Bemisia tabaci (biotype B) resistance to neonicotinoid insecticides imidacloprid, acetamiprid and thiamethoxam, and pyrethroid bifenthrin was conducted in Cyprus. The resistance level to eight field‐collected B. tabaci populations was investigated. The activities of enzymes involved in metabolic detoxification and the frequencies of pyrethroid and organophosphates target site resistance mutations were determined. Moderate to high levels of resistance were detected for imidacloprid (resistance factor [RF] 77–392) and thiamethoxam (RF 50–164) while low resistance levels were observed for acetamiprid (RF 7–12). Uniform responses by the Cypriot whiteflies could be observed against all neonicotinoid insecticides. No cross‐resistance between the neonicotinoids was detected as well as no association with the activity of the P450 microsomal oxidases. Only imidacloprid resistance correlated with carboxylesterase activity. Low to extremely high resistance was observed for insecticide bifenthrin (RF 49–1 243) which was associated with the frequency of the resistant allele in the sodium channel gene but not with the activity of the detoxification enzymes. Finally, the F331W mutation in the acetylcholinesterase enzyme ace1 gene was fixed in all B. tabaci populations from Cyprus.  相似文献   

12.
German Landrace pigs (n= 1500) were halothane-tested and blood samples were taken for the determination of A-O and H blood types as well as for the determination of PHI and 6-PGD isozymes. The pigs originated from two generations (7th and 8th) of a selection experiment ‘selection for activity of NADPH-generating enzymes in backfat of pigs’. The selection lines are E-, E+ (selection for low and high enzyme activity), U- (selection for low ultrasonic backfat thickness) and K (control). Preliminary results show an average proportion of halothane-susceptible animals of 49 %. The frequencies of halothane-positive pigs amount to 60 %, 46 %, 70 % and 30 % in lines E-, E+, U- and K, respectively. The investigation shows a non-random combination of the marker genes caused by linkage disequilibrium, especially in line E-. Recombination frequencies between the loci vary from 0 % to 18 %.  相似文献   

13.
One of the many potential uses of the HapMap project is its application to the investigation of complex disease aetiology among a wide range of populations. This study aims to assess the transferability of HapMap SNP data to the Spanish population in the context of cancer research. We have carried out a genotyping study in Spanish subjects involving 175 candidate cancer genes using an indirect gene-based approach and compared results with those for HapMap CEU subjects. Allele frequencies were very consistent between the two samples, with a high positive correlation (R) of 0.91 (P<<1×10−6). Linkage disequilibrium patterns and block structures across each gene were also very similar, with disequilibrium coefficient (r 2) highly correlated (R=0.95, P<<1×10−6). We found that of the 21 genes that contained at least one block larger than 60 kb, nine (ATM, ATR, BRCA1, ERCC6, FANCC, RAD17, RAD50, RAD54B and XRCC4) belonged to the GO category “DNA repair”. Haplotype frequencies per gene were also highly correlated (mean R=0.93), as was haplotype diversity (R=0.91, P<<1×10−6). “Yin yang” haplotypes were observed for 43% of the genes analysed and 18% of those were identical to the ancestral haplotype (identified in Chimpazee). Finally, the portability of tagSNPs identified in the HapMap CEU data using pairwise r 2 thresholds of 0.8 and 0.5 was assessed by applying these to the Spanish and current HapMap data for 66 genes. In general, the HapMap tagSNPs performed very well. Our results show generally high concordance with HapMap data in allele frequencies and haplotype distributions and confirm the applicability of HapMap SNP data to the study of complex diseases among the Spanish population. Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.  相似文献   

14.
This paper reports the distribution of blood groups, A-B-H secretors, haptoglobins, transferrins and hemoglobin types among Indians of the Gila River Valley in Arizona. Specimens were procured from the following putative full-bloods: 909 Pima, 37 Papago, and 124 Maricopa; and from the following known mixed-bloods: Pima-Papago 134, Pima-Maricopa 26, Pima-Other Indian 41, Pima-Caucasian 33. These 1304 samples were tested for factors in the A-B-O, M-N-S-s, P, Rh-Hr, Lutheran, Kell-Cellano, Lewis, Duffy, Kidd and Diego blood group systems, and for additional blood factors (Wra), Doa, Vel, Yta, Coa, Gya, Sav, and L. W. Serum samples were tested for haptoglobins and transferrins. Hemolysates, prepared from whole blood, were tested for hemoglobin types. The results are presented on appropriate tables as number and per cent of phenotypes for the various blood group antigens and their calculated allele frequencies. Locations of the populations from which blood samples were procured are shown on a map (fig. 1). Tests made by earlier workers on the blood of Arizona Indians and related tribes are presented for comparison and discussed. The usual high frequencies for allele O reported in Amerinds was found among the putatively full-blood Gila Indians; the 124 Maricopa presented the maximum frequency of 1.000. High frequencies were reported generally for M, s, P1, R1 (CDe), R2 (cDE), k (100%) Fy, and Doa alleles. Low frequencies were reported for N, S, r (cde), R° (cDe), fy, Le1w and Dia (Pima only). There was a wide variation in frequencies for jk, and Hp1, and there were 17 Transferrin Tf B1C observed in 270 Pima samples tested. All the remaining were classified as Tf C except two Tf B;C from mixed-bloods. All samples tested for Vel, Yta, Coa, Sav, and Hemoglobin (A) showed the maximum frequency (1.000) for their genes. The following antigens were completely absent: Lua, Mia, Vw, Mta, p, Pk, ry (CdE), K, and Wra. The results of this study suggests that the Papago tribe presents fewer genes of non-Indian origin than the Pima, and the Maricopa least of the three populations.  相似文献   

15.
This seventh and last paper in a series on the distribution of blood groups among Indians in South America reports the findings among Amerinds in Argentina. Blood specimens were procured from putative full-bloods of the following tribes: 38 Diaguita (Calchaqui), 230 Mataco, 90 Chiriguano, 142 Choroti, 51 Toba, 120 Chané, 96 Chulupi (Ashluslay), and 178 Araucano (Mapuche). These 945 samples were tested for blood factors in the A-B-O, M-N-S-s, P, Rh-Hr, K-k, Lewis, Duffy, Kidd, and Diego systems. Serum samples were tested for haptoglobins and transferrins. Hemolysates prepared from whole blood were tested for hemoglobin types. The results are presented in tables as phenotype distribution and calculated allele frequencies. Locations of the populations from which blood samples were procured are shown on a map of North and Central Argentina. High frequencies are reported for the O allele. Allele frequencies are high also for M, s, R1 (CDe), R2 (cDE), k, LeH and Fy. They are usually low or absent for alleles B, N, S, Mia, Vw, Ro (cDe), r (cde), K, Le1, and fy. The Di allele ranged from 0.013 in the Araucano (Mapuche) to 0.192 in the Toba. Allele frequencies aberrant for Indians were observed more often in the Araucano (Mapuche) and Diaguita tribes, due probably to greater inflow of non-Indian genes into their gene pool and perhaps also to genetic drift in small inbred populations. Hp1 allele frequencies varied from 0.43 in the Choroti to 0.80 in the Diaguita. All samples tested for transferrins except six contained the variant Tf C; the six were B1 C present in samples from one Mataco and six Araucano persons. All the specimens tested electrophoretically for hemoglobin types contained only (A) as a major component.  相似文献   

16.
The colonization patterns of oceanic islands are often interpreted through transmarine dispersal. However, in islands with intense human activities and unclear geological history, this inference may be inappropriate. Cyprus is such an island, whose geotectonic evolution has not been clarified yet to the desired level for biogeographical reconstructions, leaving the questions of ‘how the Cypriote biota arrived’ and ‘does the dispersal have the formative role in patterns of its diversification’ unanswered. Here, we address these issues through a reconstruction of the evolutionary history of six herptiles (Ablepharus budaki, Ophisops elegans, Acanthodactylus schreiberi, Telescopus fallax, Pelophylax cf. bedriagae, and Hyla savignyi) by means of mitochondrial DNA (cytochrome b and 16S rRNA), applying a Bayesian phylogenetic, biogeographical, and chronophylogenetic analyses. The phylogeographical analyses show that the colonization history of those species in Cyprus started in the late Miocene and extended into the Pliocene and Pleistocene, with geodispersal, transmarine dispersal, and human‐mediated dispersal having their share in shaping the diversification of Cypriote herptiles. The revealed patterns could be divided into three biogeographical categories: old colonizers that arrived in Cyprus during the late Miocene or early Pliocene either by a land bridge (geodispersal) which connected Cyprus with the mainland or by transmarine dispersal, younger colonizers that reached the island through transmarine dispersal from the Middle East, and new settlers that arrived through human‐induced (voluntary or not) introductions. This work advances our knowledge of the biogeography of Cyprus and highlights the need to consider both geo‐ and transmarine dispersal when dealing with islands whose associations do not have a straightforward interpretation. © 2013 The Linnean Society of London  相似文献   

17.
Ankylosing spondylitis (AS) is a rhematoid arthritis, which is a common autoimmune disease with a complex genetic etiology. Although HLA-B27 has been identified to be associated with AS, a number of other genes may also be involved in the disease. Fc receptor-like 3 (FCRL3) gene has been shown to be associated with rheumatoid arthritis in Japanese population. Here we aim to explore the association FCRL3 gene and susceptibility to human leukocyte antigen (HLA)-B27-positive AS in Han Chinese population. Among 169 AS patients, the frequencies of C and T (rs7522061) in FCRL3 gene were 38.7 and 61.3%, respectively; in 184 controls (HLA-B27-positive), the frequencies of C and T were 38.6 and 61.4%, respectively. The frequencies of alleles and genotype are not of statistically significant difference in two groups (χ2 = 0.000, P = 0.983; χ2 = 0.099, P = 0.952, respectively),but the distribution of HLA-B27 subtypes are statistically significant difference between cases and controls (χ2 = 8.214, P = 0.042). Our data reveal that the FCRL3 gene does not appear associated with susceptibility to HLA-B27-positive AS in Han Chinese population.  相似文献   

18.
Summary Two closely linked mutations, U20 and M87, in the deletion group V. of the transferase gene of the galactose operon in E. coli were crossed against a set of other mutations in the epimerase, transferase and kinase genes of the galactose operon by P1 transduction. U20 is an amber mutation. Its Gal + frequencies are higher by a factor of 2 to 10 than those of M87. Two double mutants of U20 with other gal mutations do not show these Gal + frequencies in similar crosses. The results can be explained on the assumption that in heteroduplexes U20 is repaired to yield wildtype at higher rate than is M87.  相似文献   

19.
Summary Electrofocusing and agarose electrophoresis techniques both reveal polymorphism of ESD 2, which may be subdivided into two different proteins, coded for by genes allelic to ESD *1. After agarose electrophoresis, ESD 2 is slightly more anodally located than ESD 5, while the latter is considerably more acidic as revealed by electrofocusing in polyacrylamide gel slabs. Family studies have confirmed that each of the allele products behave as Mendelian characters: and the gene frequencies in a Norwegian population material are about 0.08 and 0.02 for the ESD *2 and ESD *5 alleles, respectively.  相似文献   

20.
The aim of the present work is to estimate the usefulness of microsatellite genetic markers analysis to characterize and analyze the possible differences between a captive reared population and a wild one from the same species. The first sample consists of 27 chukar partridges (Alectoris chukar) bred in one farm in Argentina. The second one is composed of 31 chukar partridges coming from a wild Cyprus population (A. chukar cypriotes). We analyzed seven microsatellite loci: MCW135, MCW225, MCW276, MCW280, MCW295, LEI31, and ADL0142. The Argentina group showed higher genetic variation than the Cyprus did. Significant global F IS value was found in the Argentina sample. Significant genetic differentiation exists between both groups (F ST=0.394; p<0.01). The Argentina group did not show any signs of bottleneck. Results from Factorial Correspondence Analysis (FCA) suggest that the 58 partridges could be split into two distinct genetic clusters (Cyprus and Argentina). Nevertheless, in the light of PARTITION results, three Argentina individuals might be related to Cyprus. STRUCTURE is unable to assign these three animals to any of the two groups. This could be due to a single or repeated introduction of external individuals into the original Argentina group, so that these results would point to more than one origin for this population. This admixture of individuals could explain the high genetic variation observed in the Argentina farm. Global F IS value would probably be higher without these immigrations; on the other hand, these admixtures could have prevented bottlenecks.  相似文献   

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