RESUMO
The age-related dynamics of chromosomal instability and germination capacity of welsh onion (Allium fistulosum L.) seeds have been studied under two different storage temperatures during six years after harvesting. Seeds that were kept at the room temperature (14-28 degrees C) during 6 years of storage have lost their germination capacity. The frequencies of aberrant anaphases grew from 2% on the first month of storage up to 80% on the 75th month of storage. The germination capacity of seeds kept at the lower temperature (4-9 degrees C) was 73-77% on the 6th year of storage and the frequency of aberrant anaphases remained within the limits of 2-4%. Thus, storage of welsh onion seeds during 6 years at the lower temperature allows to retain germination capacity and restrains the augmentation of chromosomal instability in root meristem cells of seedlings during this period.
Assuntos
Allium/genética , Instabilidade Cromossômica/genética , Cromossomos de Plantas , Allium/crescimento & desenvolvimento , Germinação/genética , Cinética , Sementes/genética , Sementes/crescimento & desenvolvimento , Temperatura , Fatores de TempoRESUMO
The results of study of micronuclei (MN) frequencies among the participants of Ukrainian school biological olympiads are presented. Totally 266 persons have been inspected. The distribution of MN frequencies correspond to the Poisson's distribution with lambda = 2.5. The average frequency of micronuclei in males was 2.4 +/- 0.15%, in females it was 2.7 +/- 0.14%. The difference of the average MN frequencies for these two groups was statistically insignificant. The individual micronuclei frequencies varied from 0 to 8.3%, the average MN frequency in the general group was 2.5 +/- 0.11%, (limits 2-5%). The micronuclei frequencies in different age groups of males and females were compared. Significantly higher MN frequencies in females than in males at the age of sixteen were detected. The age-related changes of micronuclei frequencies (14-18 age) were different for females compared to males.
Assuntos
Envelhecimento/genética , Instabilidade Genômica , Micronúcleos com Defeito Cromossômico , Mucosa Bucal , Caracteres Sexuais , Adolescente , Feminino , Humanos , Masculino , Micronúcleos com Defeito Cromossômico/estatística & dados numéricos , Testes para Micronúcleos , Mucosa Bucal/citologia , Distribuição de Poisson , UcrâniaRESUMO
The chromosome aberrations in root meristem cells of welsh onion (Allium fistulosum L.) seeds after gamma-irradiation (5 and 10 Gy) of different-aged seeds (7, 19, 31, 43 and 55 months of storage) were studied. The irradiation dose of 5 Gy significantly increased the frequency of aberrant anaphases (FAA) for 31- and 43-months seeds; the dose of 10 Gy significantly increased the FAA in seeds of all age groups. The irradiation of young (7 months) seeds resulted in decreasing of the fraction of bridges to the control level of the old (55-months) seeds for the dose of 5 Gy and below the control level of the old seeds--for the dose of 10 Gy. Some peculiarities of cytogenetic parameters of genome instability and the germinating capacity of the seeds made it possible to suppose that the third year of storage is a critical period for the welsh onion seeds.
Assuntos
Allium/crescimento & desenvolvimento , Instabilidade Cromossômica/efeitos da radiação , Raios gama , Allium/genética , Allium/efeitos da radiação , Instabilidade Cromossômica/genética , Cromossomos de Plantas/genética , Cromossomos de Plantas/efeitos da radiação , Relação Dose-Resposta à Radiação , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/efeitos da radiação , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/efeitos da radiação , Fatores de TempoRESUMO
RAPD analysis was used to examine the extent of genetic polymorphism in two populations of Gentoo penguin (Pygoscelis papua) from Antarctic Islands (Petermann and Livingston). The chosen two of three 10 mer oligonucleotide primers accordingly to preliminary results showed different levels of polymorphism in Gentoo penguins at Petermann Island (from 23.53 to 42.86%) and Livingston Island (from 52.94 to 57.14%). Nei's similarity coefficients were in range from 0.5606 (when Gentoo genome profiles were compared with RAPD profiles of two related penguin species: Pygoscelis adeliae (Adelie) and Pygoscelis antarctica (Chinstrep)) to 0.9281 among observed Gentoo penguin populations. Nei's distances values ranged from 0.0746 to 0.5787 among the populations and species. The obtained results will be used for further estimation of genetic diversity of Gentoo penguins and determination of their taxonomic status.
Assuntos
Genética Populacional , Polimorfismo Genético , Spheniscidae/genética , Animais , Regiões Antárticas , Classificação , DNA/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Spheniscidae/sangue , Spheniscidae/classificaçãoRESUMO
The average number of aberrations per aberrant cell was concluded to carry out information on chromosome instability peculiarities induced by different mutagens as it was shown in our previous work. The purpose of the current study was to present comparative analysis of intercellular distribution of number of aberrations and their theoretical approximations. Distribution of numbers of aberrations per cell in Allium cepa L. and Allium fistulosum L. root tip cells induced by different mutagenic factors (gamma-irradiation, thiotepa, formaldehyde and seed aging) have been studied. The results were approximated to theoretical Poisson, geometric and negative binomial distributions. The intercellular distribution of aberrations did not correspond to any of the used theoretical distributions when A. cepa seeds were gamma-irradiated. There was some, but not regular, accordance with theoretical distributions when chemical mutagens thiotepa in A. cepa and formaldehyde in A. fistulosum and seed aging in both species were evaluated. During seed aging frequency of aberrant cells increased more quickly in A. fistulosum in comparison with A. cepa.
Assuntos
Allium/genética , Instabilidade Cromossômica/genética , Cromossomos de Plantas/genética , Raios gama , Meristema/genética , Mutagênicos/toxicidade , Allium/efeitos dos fármacos , Allium/efeitos da radiação , Aberrações Cromossômicas/estatística & dados numéricos , Meristema/efeitos dos fármacos , Meristema/efeitos da radiação , Modelos Genéticos , Distribuição de PoissonRESUMO
The estimation of individual variability and group dynamics of micronuclei rate in buccal cells of participants of transatlantic march of the VIIth Ukrainian Antarctic expedition (Sevastopol--UAS "Akademik Vernadsky"--Sevastopol) was carried out. The general average rate of micronuclei was 2.20 per thousand. Individual values of micronuclei frequencies varied in wide limits. The maximum value of CV was 92.4% and the minimal one was 48.4%. Individual averages of micronuclei rates varied from 1.70 to 2.78 per thousand. Dependence of individual and group dynamics of micronuclei rates on environmental factors (temperature, atmospheric pressure and storm activity) was tested. No significant correlation of these parameters was found.
Assuntos
Adaptação Fisiológica/fisiologia , Expedições , Micronúcleos com Defeito Cromossômico , Adulto , Idoso , Regiões Antárticas , Humanos , Masculino , Testes para Micronúcleos , Pessoa de Meia-Idade , Mucosa Bucal/citologia , Reprodutibilidade dos Testes , UcrâniaRESUMO
Analysis of chromosome instability (CI) is of great importance in view of pollution of the environment by genotoxic factors. Frequency of aberrant cells, spectrum of chromosome aberrations, damages of aberrant cell and distribution of aberrations in the cells are the most conventional parameters of CI. We have carried out the comparative analysis of the frequency of aberrant cells and the dynamics of aberrant cell damages induced by different mutagenic factors (alpha-irradiation from 241Am, gamma-irradiation from 60Co and tioTEPA) in Allium-test. This comparative analysis denotes that the studied parameters have different dynamics characterizing different mechanisms of CI in Allium cepa L.
Assuntos
Aberrações Cromossômicas , Mutagênicos , Allium/efeitos dos fármacos , Allium/genética , Allium/efeitos da radiação , Partículas alfa/efeitos adversos , Amerício/toxicidade , Antineoplásicos Alquilantes/efeitos da radiação , Radioisótopos de Cobalto/efeitos da radiação , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Raios gama/efeitos adversos , Tiotepa/efeitos da radiaçãoRESUMO
Large-scale estimation of micronuclear index in the population of different physical-geographic regions near Chernivtsi was performed for the first time. The authors managed to reveal the correlation between the rate of genetic changes in children from Bukovyna and the level of soil and water contamination with heavy metals and aluminum in settlements examined.
Assuntos
Micronúcleos com Defeito Cromossômico , Mutação , Alumínio/toxicidade , Criança , Humanos , Metais Pesados/toxicidade , Poluentes do Solo/toxicidade , Ucrânia , Poluentes da Água/toxicidadeRESUMO
A model of correlative variability of AB0 blood groups and a quantitative trait (mad-model) was analysed. Statistics for evaluation of additive and non-additive effects of alleles IA, IB and i on quantitative trait were developed. Restrictions of the model application are discussed. The obtained results may be used in genetic epidemiology for study of sensitivity or resistance to different diseases.
Assuntos
Sistema ABO de Grupos Sanguíneos , Marcadores Genéticos , Característica Quantitativa Herdável , Humanos , Modelos GenéticosRESUMO
Statistics for estimation of additive and non-additive effects of marker gene on quantitative trait are developed from the mad-model of a quantitative trait for three-allelic codominant marker locus. All they may be obtained directly from population data, without any hybridological experiments.
Assuntos
Alelos , Variação Genética/genética , Modelos Genéticos , Animais , Genes Dominantes/genética , Marcadores Genéticos/genética , Genótipo , Humanos , Vigor Híbrido/genética , Modelos EstatísticosRESUMO
The effect of duration of cultivation of lymphocytes of human UV-irradiated peripheral blood on the chromosomal aberration rate was studied. Under prolonged cultivation the more irradiated blood samples revealed higher level of chromosomal aberrations. The existence of UV-induced delayed chromosomal instability is supposed that may be found under prolonged cultivation. The mechanisms of this phenomenon are discussed.
Assuntos
Aberrações Cromossômicas/genética , Linfócitos/efeitos da radiação , Raios Ultravioleta , Técnicas de Cultura de Células/métodos , Células Cultivadas , Distribuição de Qui-Quadrado , Humanos , Metáfase/efeitos da radiação , Mitose/efeitos da radiação , Fatores de TempoRESUMO
The influence of thymogene on the frequency of spontaneous and formaldehyde-induced chromosome aberrations in human peripheral blood lymphocytes was detected. High thymogene concentration (1000, 100, and 10 micrograms/ml) significantly decreased the proliferative activity of lymphocytes in culture. Low thymogene concentrations (1.0; 0.1; 0.01; and 0.001 microgram/ml) didn't decrease the mitotic activity of culture and hadn't mutagenic activity. Thymogene concentrations 1.0; 0.1; and 0.001 microgram/ml significantly decreased the frequency of formaldehyde-induced chromosome aberrations in lymphocytes. Possible mechanisms of gene protection by thymogene is discussed.
Assuntos
Adjuvantes Imunológicos/farmacologia , Aberrações Cromossômicas , Dipeptídeos , Linfócitos/efeitos dos fármacos , Peptídeos/farmacologia , Células Cultivadas , Relação Dose-Resposta a Droga , Formaldeído/farmacologia , Humanos , Linfócitos/ultraestrutura , Metáfase/efeitos dos fármacos , Mutagênicos/farmacologiaRESUMO
Peculiarities of interdependent variation of monogenic and polygenic traits were analyzed using a one-locus diallelic model of a monogenic, dominantly inherited trait. The possibility of determining the mean genotypic value of the trait (m) and also the additive (a) and nonadditive (d) effects of the interaction between alleles of a monogenic trait on a quantitative trait is considered. It is shown that a and d can differ from zero even if the mean values in the groups with dominant and recessive phenotypes are equal. Equations are presented that allow the direct use of data obtained in population studies for determining m, a, and d, as well as corresponding standard errors under the conditions of codominance and dominance of the monogenic trait. Another group of equations allows determination of the sample size necessary for calculating m, a, and d. The problem concerning the ambiguity of m, a, and d values calculated using the proposed equations is discussed. This ambiguity depends on the fact that identification of genotypes in the case of a dominantly inherited monogenic trait is impossible.
Assuntos
Evolução Biológica , Genes Dominantes , Genes Recessivos , Variação Genética , Alelos , Mapeamento Cromossômico , Marcadores Genéticos , Genótipo , Matemática , Modelos Genéticos , Mutação , Fenótipo , Reprodutibilidade dos Testes , Seleção GenéticaRESUMO
The aim of the work was to analyse some regularities of correlative variability of qualitative and quantitative characters. The simplest classical model of quantitative character was used for study of the dependence of mean (X) and variance (V) of quantitative character on the genotypic composition of the group, on peculiarities of alleles relations with quantitative character and on the allele frequencies (q). Two types of the genotypic groups were discriminated: homogeneous and heterogeneous ones. In homogeneous groups V = 0; X and V are independent of the q. In heterogeneous ones V > 0 and both of X and V depend of the q. Specific contribution of additive and dominant allelic effect on the group genotypic composition and also on the q. It is possible to determine the expected value of X and V for any group of known genotypic composition on the base of data calculated from direct measures of individuals in the sample. The expected differences of variances in homogeneous group of heterozygotes and heterogeneous ones of homozygotes (1/1 + 2/2) become significant since expected genotypic variance of last group is equal or more than 0.4VE, where VE--nongenotypic variance. The need of taking into consideration expected X and V under comparing quantitative character in groups with different genotypic compositions is discussed.
Assuntos
Alelos , Variação Genética , Modelos Genéticos , Mapeamento Cromossômico , Frequência do Gene , Genes Dominantes , Genótipo , Homozigoto , Humanos , Polimorfismo GenéticoRESUMO
Two fractions of rat liver nuclei with different buoyant density have been obtained. The electrophoretic analysis of the oligonucleosome patterns of DNA out of nuclei of these two fractions revealed different levels of activity in endonucleases. In case of inhibition during the extraction of activity in Ca, Mg-dependent endonucleases, the average size of high polymeric DNA is larger for nuclei with bigger buoyant density (fraction I) than for nuclei with smaller ones (fraction II). This finding is evidence of in situ existence of two pools of liver nuclei with different endogenic nuclease activities. In nuclear chromatin fraction I DNA is torsionally stressed; in fraction II it is relaxed that correlates with larger activity of endonucleases and smaller buoyant density of this fraction. A hypothesis on a possible role of endonucleases in chromatin structure organization has been put forward. According to this hypothesis a modulation of activity in nuclear endonucleases can determine different packaging and activity of chromatin from different pools of cellular nuclei.
Assuntos
Cromatina/química , Desoxirribonucleases/química , Animais , Fracionamento Celular/métodos , Núcleo Celular/química , DNA/análise , DNA/isolamento & purificação , Desoxirribonucleases/análise , Fígado/química , Ratos , Ratos Wistar , Espectrometria de Fluorescência/métodosRESUMO
The relationships of heterozygosity with the mean and variance of quantitative character were considered under neutrality, additivity and overdominance of polymorphic loci. Attention was drawn to dependence of the patterns of relationships on the number of polymorphic loci (which varied from 1 to 10) and on the type of polymorphic loci, both homogeneous (polymorphic loci are of the same type) and heterogeneous (polymorphic loci are of the two types) samples of 10 polymorphic loci and their combination. It is shown that increase in the number of polymorphic loci is accompanied with extension of the limits of corresponding relations, whereas the patterns of these relations depend on the type of connection of separate polymorphic locus with the quantitative character and on the ratio of different loci in the set of polymorphic loci. It is assumed that the relationship of heterozygosity with quantitative characters, displayed in the number of experimental works, may contain a component mediated by similar statistical effects. It is inferred that the discrepancy between different authors' experimental data on existence or lack of some relationships between multiplicative heterozygosity and morphological variability of quantitative characters can be explained by different types of relations of polymorphic loci to quantitative characters encountered in their works.
Assuntos
Heterozigoto , Modelos Genéticos , Alelos , Matemática , Polimorfismo GenéticoRESUMO
The term "pseudopolymorphism" refers to a situation, where there is no simple correspondence between genotype and phenotype: a single genotype may be moulded into several phenotypes. It is known that broad substrate specificity of enzymes may be one of the causes for pseudopolymorphism. This article deals with the other cause for this phenomenon--a consequence of post-translation modifications, such as limited proteolysis. Variability of some enzymes of grass carp Ctenopharyngodon idella Val. (Pisces, Cyprinidae) was studied by gel electrophoresis. It was found that variability of isozyme patterns of lactate dehydrogenase (LDH), glucose-6-phosphate dehydrogenase (G-6-PDH), malic enzyme (ME) and esterase (EST) is connected with the differences in protease activity of grass carp liver homogenates. The fish isozyme patterns of high (and, partially, intermediate) proteinase activity had some anomalies: displacement of fractions, one or several additional fractions, decreased activity of single fractions or the whole spectrum. In some cases, this variability looked like a classical polymorphic system specified by two alleles of one locus. The effect of enzymes' and proteins' modifications on electrophoretical pseudopolymorphism is discussed.