Genetika最新文献

The aim of this study was to determine the effect of genotype and induction medium in anther culture of wheat (Triticum aestivum L.). Ten F1 winter wheat genotypes were tested in anther culture (AC) to compare the two most frequently applied induction media (W14mf and P4mf). Androgenesis was induced during the treatment of each tested genotypes and green plants were produced from them using both media. Based on statistical analysis, the genotypes significantly influenced (at the 0.001 probability level) the efficiency of AC (embryo-like structures (ELS), albinos, green plantlets and transplanted plantlets) and the media also had a significant effect on the number of ELS and albino plantlets. Both media can be used for AC in wheat doubled haploid (DH) plant production. The production of ELS and green plantlets was higher in P4mf medium (48.84 ELS/100 anthers, 4.82 green plantlets/100 anthers) than in W14mf medium (28.14 ELS/100 anthers, 4.59 green plantlets/100 anthers). However, the green plant regeneration efficiency of the microspore-derived structures was 16.9% when using W14mf medium, while this value was 9.6% in the case of ELS induced with P4mf medium. The application of W14mf medium thus proved to be time- and labour-saving medium in the large-scale production of DH wheat plants. In our experiments, 267 DH plants were produced for our winter wheat breeding program. The spontaneous rediploidization rate was 32.72%.

Authentic identification of fish species is essential for conserving them as a valuable genetic resource in our environment. DNA barcoding of living beings has become an important and ultimate tool for establishing their molecular identity. Among cyprinids, Barilius is an important genus having nearly 23 species in Indian region whose morphological identification is often difficult due to minute differences in their features. Five species collected from Indian waters and primarily identified as Opsarius bakeri (syn. Barilius bakeri), B. gatensis, B. vagra, B. bendelisis and B. ngawa were authenticated by their DNA barcoding based on mitochondrial COI gene sequences. Five individuals of each species were taken for barcode preparation by COI gene sequencing which yielded one barcode for B. ngawa, two barcodes each for O. bakeri, B. gatensis, B. bendelisis and three barcodes for B. vagra. The order of inter and intra-specific variation was estimated to know a preliminary status of variation prevailing in these cold stream fish species significant for evolution and conservation of these valued species of our ichthyofauna. Average variation within genera was found to be 13.6% with intra-specific variation ranging from 0.0% (B. ngawa) to 0.6% (B. gatensis). These distance data are in the same order found by various researchers globally using COI barcode sequences in different fish species. Phylogenetic relatedness among Barilius species and some other cyprinids validate their status of individual species as established by conventional taxonomy.

In the present study, the frequencies of genotypes and alleles of candidate genes with respect to polymorphisms associated with increased pregnancy loss in the first trimester of pregnancy, including MMP1–1607insG, MMP9 A–8202G, and TIMP1 С536T, were reported. The frequency of homozygotes for allele MMP9 A–8202 was increased by a factor of two among women with miscarriage in the first trimester compared to the control. Significant models of interaction of genes MMPs and TIMP1 were revealed. The genotypes of genes MMP1 (rs1799750), MMP9 (rs11697325), and TIMP1 (rs11551797) increasing the risk of pregnancy loss in the first trimester were determined.

Integration of the methods of contemporary genetics and biotechnology into the breeding process is assessed, and the potential role and efficacy of genome editing as a novel approach is discussed. Use of molecular (DNA) markers for breeding was proposed more than 30 years ago. Nowadays, they are widely used as an accessory tool in order to select plants by mono- and olygogenic traits. Presently, the genomic approaches are actively introduced into the breeding processes owing to automatization of DNA polymorphism analyses and development of comparatively cheap methods of DNA sequencing. These approaches provide effective selection by complex quantitative traits, and are based on the full-genome genotyping of the breeding material. Moreover, biotechnological tools, such as doubled haploids production, which provides fast obtainment of homozygotes, are widely used in plant breeding. Use of genomic and biotechnological approaches makes the development of varieties less time consuming. It also decreases the cultivated areas and financial expenditures required for accomplishment of the breeding process. However, the capacities of modern breeding are not limited to only these advantages. Experiments carried out on plants about 10 years ago provided the first data on genome editing. In the last two years, we have observed a sharp increase in the number of publications that report about successful experiments aimed at plant genome editing owing to the use of the relatively simple and convenient CRISPR/Cas9 system. The goal of some of these experiments was to modify agriculturally valuable genes of cultivated plants, such as potato, cabbage, tomato, maize, rice, wheat, barley, soybean and sorghum. These studies show that it is possible to obtain nontransgenic plants carrying stably inherited, specifically determined mutations using the CRISPR/Cas9 system. This possibility offers the challenge to obtain varieties with predetermined mono- and olygogenic traits.

The problem of development and dispersion of complex diseases in human populations requires new views, approaches, hypotheses, and paradigms. Evolutionary medicine provides one of the promising approaches to this problem, putting the disease into an evolutionary context. Unlike classic approaches oriented to proximate issues on structure and mechanisms of a disease, evolutionary considerations are broader. It provides the basis for understanding the origin, dispersion, and maintenance of the high frequencies of pathological phenotypes in modern human populations. In the current paper, we try to review the modern concepts on the evolution of human genetic diversity, to shape the outlines of evolutionary medicine, and to illustrate evolutionary medical problems using our experimental data. Data on genome-wide search for the signals of decanalization and adaptation in the human genome and on related biological processes and diseases are presented. Some hypotheses and concepts of evolutionary medicine may be productive for revealing the mechanisms of origin and dispersion of complex diseases and for pathogenetics of multifactorial diseases. One of such concepts is the hypothesis of decanalization of genome–phenome relationships under natural selection during modern human dispersion. Probably, the high frequency of alleles associated with complex diseases (and partially the high prevalence of diseases themselves) could be explained in the framework of the hypothesis.

The review discusses the causes of multiple failures in cancer treatment, which might primarily result from the excessive variability of cancer genomes. They are capable of changing their spatial and temporal architecture during tumor development. The key reasons of irreproducibility of biomedical data and the presumable means for improvement of therapeutic results aiming at targeting the most stable tumor traits are suggested.

This review summarizes the results of the long-term studies performed at the Institute of General Genetics, Russian Academy of Sciences, in the field of genetic demography of migration processes in Russia and its capital. The main population-genetic parameters of migration and their dynamics in Moscow over a hundred years are given. Sociodemographic and population-genetic implications of migration processes are considered. A model predicting the population gene pool dynamics under migration pressure for genes of different localization (autosomal, sex-linked, and mitochondrial), exemplified by predicting the allele frequency dynamics in the Moscow population of some gene markers, including genes accounting for monogenic pathology and genes associated with resistance to socially significant diseases, are presented. The paper discusses the selective character of migration processes, in particular, processes of emigration, with respect to some genetically significant ethnodemographic traits; the problem of adaptation of migrants; and adaptive strategies of consolidation of ethnoconfessional groups in the megalopolis (compact settlement over the urban territory and positive assortative mating with respect to demographic traits). It was shown that, owing to the intense influx of migrants and gene flows between ethnic groups, the population of the megalopolis is of mixed origin in terms of ethnic, anthropologic, and genetic aspects. The results of the study suggest the necessity to develop a specific strategy of genetic database formation for the population of megalopolises for the purposes of medical genetics and forensic medicine.

Phenomics is a field of science at the junction of biology and informatics which solves the problems of rapid, accurate estimation of the plant phenotype; it was rapidly developed because of the need to analyze phenotypic characteristics in large scale genetic and breeding experiments in plants. It is based on using the methods of computer image analysis and integration of biological data. Owing to automation, new approaches make it possible to considerably accelerate the process of estimating the characteristics of a phenotype, to increase its accuracy, and to remove a subjectivism (inherent to humans). The main technologies of high-throughput plant phenotyping in both controlled and field conditions, their advantages and disadvantages, and also the prospects of their use for the efficient solution of problems of plant genetics and breeding are presented in the review.

Horizontal gene transfer (HGT) is widespread in the world of prokaryotes, but the examples of this phenomenon among multicellular animals, particularly insects, are few. This review examines the transfer of genetic material to the nuclear genomes of insects from the mitochondrial genome (intracellular HGT), as well as from the genomes of viruses, bacteria, fungi, and unrelated insects. In most cases, the mechanisms of this transfer are unknown. Many pro- and eukaryotic genes that moved through the HGT are expressed in the insect genome and in some cases can provide the evolutionary innovations that are considered as aromorphoses.