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Modern sheep breeding should be based on the production of high quality sheep products. Knowing the limits of animal productivity potential allows to manage the breeding process in the most effective way. Applying PCR-RFLP method makes it possible to identify allelic variants of genes associated with quantitative and qualitative characteristics of animals. By identifying different polymorphic variations and their phenotypic manifestations, one can create and replenish a database for managing the genetic progression of breeding-significant traits. The paper determines the gene polymorphism of growth hormone (GH), calpastatin (CAST) and growth differentiation factor (GDF9) of experimental animals and reflects an associative connection between the dynamics of growth and that of development of crossbred one-shear sheep of different origin (Russian meat merino ewes and imported producers). The article concludes that in order to increase sheep meat productivity, farms should give preference to animals carrying genes with the identified desired genotype on the studied polymorphisms and take into account their presence in the breeding process.

Wheatgrass (Th. intermedium) has been traditionally used in wheat breeding for obtaining wheat-wheatgrass hybrids and varieties with introgressions of new genes for economically valuable traits. However, in the 1980s in the United States wheatgrass was selected from among perennial plant species as having promise for domestication and the development of dual-purpose varieties for grain (as an alternative to perennial wheat) and hay. The result of this work was the creation of the wheatgrass varieties Kernza (The Land Institute, Kansas) and MN-Clearwater (University of Minnesota, Minnesota). In Omsk State Agrarian University, the variety Sova was developed by mass selection of the most winter-hardy biotypes with their subsequent combination from the population of wheatgrass obtained from The Land Institute. The average grain yield of the variety Sova is 9.2 dt/ha, green mass is 210.0 dt/ ha, and hay is 71.0 dt/ha. Wheatgrass is a crop with a large production potential, beneficial environmental properties, and valuable grain for functional food. Many publications show the advantages of growing the Kernza variety compared to annual crops in reducing groundwater nitrate contamination, increasing soil carbon sequestration, and reducing energy and economic costs. However, breeding programs for domestication of perennial crops are very limited in Russia. This paper presents an overview of main tasks faced by breeders, aimed at enhancing the yield and cultivating wheatgrass efficiency as a perennial grain and fodder crop. To address them, both traditional and modern biotechnological and molecular cytogenetic approaches are used. The most important task is to transfer target genes of Th. intermedium to modern wheat varieties and decrease the level of chromatin carrying undesirable genes of the wild relative. The first consensus map of wheatgrass containing 10,029 markers was obtained, which is important for searching for genes and their introgressions to the wheat genome. The results of research on the nutritional and technological properties of wheatgrass grain for the development of food products as well as the differences in the quality of wheatgrass grain and wheat grain are presented.

Polyposis rhinosinusitis (PRS) is a complex multifactorial disease. Genetic factors have been shown to predispose to the development of this pathology. Cytokines and disorders of Toll-like receptors play a significant role in the pathogenesis of HRP. Therefore, the identification of polymorphic variants of immune system genes that can be predictors of the disease development risk is a promising direction. This paper analyzes scientific articles on the role of expression and gene polymorphism of the most important cytokines and Toll-like receptors in the association with the predisposition and the course of this pathology. It is believed that genetic markers of HRS are important in predicting the risk of disease development, its course and the effectiveness of the therapy.

Epilepsy is a group of painful conditions caused by brain disorders, which are characterized by a persistent predisposition to epileptic seizures, as well as neurobiological, cognitive, psychological and social consequences. Currently, the overall prevalence of epilepsy in the world's population is 0.88% and ranges from 0.64% in developed countries to 1.00% in other countries. The prevalence of epilepsy in men is slightly higher than in women, and heredity varies between 25%-70%. According to the current classification, epilepsy includes four main forms: focal epilepsy, generalized epilepsy, combined focal and generalized epilepsy, and indeterminate epilepsy. The most common form of epilepsy is focal epilepsy, which accounts for 60% of all epilepsies. Currently, 14 genes associated with the development of epilepsy have been described, the functions of which are impaired by the presence of single nucleotide polymorphisms (SNPs). These SNPs can be located not only in the coding regions of genes (exons) or regulatory regions (eg., promoters), but also in their non-coding regions (introns), as well as in intergenic regions of DNA near a particular gene. Further research into the genetics of epilepsy should focus on developing new analytical approaches that will help uncover the unknown molecular genetic mechanisms of this group of disorders. Advances in the genetics of epilepsy will have a positive impact on clinical practice. [ABSTRACT FROM AUTHOR]

It has been shown in the previous paper that if one Drosophila chromosome lacks histone genes, the intact homologous chromosome has an increased number of histone genes. The present study shows that the extent of compensatory multiplication of histone genes depends on the nature of the deficient chromosome. An extra Y chromosome in the genome of flies without the deficiency does not affect their histone gene content. In heterozygotes with a deficiency of histone genes the number of these genes grows gradually and reaches 90% of the norm in the eight generation (magnification). After the deficient chromosome is eliminated the increased number of histone genes is not stably inherited and reverts to the normal level in the course of 5--7 generations. Deficiency-heterozygous males of the first generation contain extrachromosomal histone DNA and have a changed ratio of the two types of histone gene blocks. The multiplication of histone genes is compared with the compensation and magnification of rDNA.

In this paper, information about the structure and function of collagen genes family coding the main proteins of connective tissue of higher organisms is summarized. The structure of collagen proteins, their precursors and the main properties of corresponding mRNA and cDNA are discussed. The data are presented on evolution of collagen genes and their association with the human hereditary diseases of connective tissue.

A sensitive immunoassay was used to identify recombinant DNA plasmids carrying cDNA fragments of bovine caseins in the cDNA library from rRNA of bovine mammary glands. Colonies grown on nitrocellulose filters were lysed in situ and proteins from the lysates were blotted onto CNBr-activated filter paper. Antigens covalently bound to the CNBr-activated paper or bound to the nitrocellulose filters were detected by reaction with antiserum to caseins, followed by 125I-labeled protein A from Staphylococcus aureus and autoradiography. Four clones were positive among 5400 bacterial clones of the cDNA library--al, b2, b5, h7. Molecular weights of chimeric proteins pre-beta-lactamase:casein synthesized in Escherichia coli were determined by immunoblotting. Colony hybridization and DNA sequence analysis showed that clone b5 contained cDNA fragment of bovine kappa-caseins and clone h7 cDNA fragment of beta-casein. The last clone was designated pKcas beta-7.

The paper contains a short review of the data on multigene families of protein genes. Structural features and organization of a number of multigene systems coding for proteins are described as models of eukaryotic gene loci arrangements. Based on the extensive information of multigene families, the principles of eukaryotic genome organization are discussed.

Chromatin structure of ribosomal genes from nuclei of Drosophila melanogaster embryos was studied by using micrococcal nuclease cleavage. End-directed labelling with short cloned fragments of the ribosomal repeat was carried out. It shows, that the micrococcal nuclease prefers specific sites in naked DNA, and the pattern of DNA cleavage is essentially conserved when the nuclei are digested. Only minor differences are visible. Hence, there are no specific positions of nucleosomes on the ribosomal repeat. The DNA fragments from the nuclei treated with micrococcal nuclease were electrophoresed, transferred to DBM-paper and hybridized with different probes subcloned from the ribosomal repeat. The non-transcribed spacer and the region of the beginning of transcription are hydrolysed significantly faster than the coding region or inactive ribosomal insertion. The region of NTS and the beginning of transcription do not give normal nucleosomal fragment in the range of 145-185 bp; instead they produce a heterogeneous band 200-280 bp in length even after prolonged digestion. Dinucleosomal fragments are also slightly longer and more heterogeneous than in other parts of the ribosomal repeat. Higher oligomers are similar throughout the ribosomal repeat. We suggest that a hypothetical transcription factor interacts in a way with histones and protects unusual fragments of DNA from digestion.

The paper presents a survey of literature concerned with the possibility of expression of plasmid-clones genes from eukaryotic organisms in bacteria cells. Studies on bacterial synthesis of somatostatin, human insulin, hormone of rat growth and proteins: chicken ovalbumin and mouse dihydrofolate reductase are discussed.

Blast resistance genes of rice and their markers (review) Rice blast is a very harmful and dangerous disease, caused by the fungus pathogen Pyricularia oryzae Cavara риса (Oryza sativa L.). The use of the varieties resistant to the disease is one of the efficient ways to protect plants from diseases. The recent progress in rice genomics allowed using DNA-markers to grow resistant varieties through marker breeding (MAS). The article summarizes the information about blast resistance genes of rice and their markers, which can be used in breeding. The article gives the data about registered genes and their number, chromosome loci, regularities of stability, samples-donors and molecule characteristics of cloned genes. Besides, several questions about a nomenclature system and identification of resistance genes have been considered in the paper. The information can help rice breeders improve rice blast resistance through marker breeding. ARRIGC together with ARRI of rice and SFU have started breeding rice varieties resistant to blast through marker breeding since 2003. Their long-term work in the introgression of resistance genes by PCR-analysis resulted in the development of the rice variety ‘Magnat’ with the genes Pi-1 and Pi-2, and in 2015 there were obtained pyramid rice lines with five rice blast resistance genes Pi-l, Pi-2, Pi-33, Pi-ta and Pi-b.

The potential of molecular approaches in the management of the technological properties of wheat grain affecting the quality of the end product of bread industry is considered. Currently, along with the growth of grain production, the traditional range of staples is crowded out, the quality of most popular bread varieties deteriorates, and dozens of different substances of biological and chemical origin are used as bread improvers. Meanwhile, the genetic potential of wheat allows the development of varieties with technological parameters of grain suitable for production of high-quality bread. In Russia, multiple examples of the creation of varieties for the production of first and second-class grain are known, and modern molecular genetics offers techniques that can supplement classical breeding approaches and accelerate the development of new varieties adapted to the conditions and requirements of the baking industry, using the natural genetic potential of wheat. We summarize the diversity of requirements for grain and flour for different end-use products. Statistics on the volume and structure of grain quality in Russia in 2011–2014 is analyzed. An essential deformation of the quality structure of the produced wheat grain in favor of less valuable classes is observed. A brief retrospective analysis of research in wheat genetics, demonstrating the contribution of genetic factors to grain and flour technological properties, is performed. Various approaches to rapid breeding of varieties with desired properties are considered in relation with the development of plant molecular genetics. The paper provides examples illustrating the feasibility of using methods of DNA diagnostics in various stages of the process, during which the genetic potential of food crops expresses itself and affects the quality of the end product. The results of molecular studies on the localization and isolation of genes determining technological properties (protein and wet gluten contents, milling properties, rheological properties, flour color, and starch properties) are reviewed. The data on diagnostic DNA markers, which are suitable for efficient selection of genotypes instead of the time-consuming analysis of technological properties during breeding process, are summarized. Thus, the information about the genetic potential of bread wheat and modern technologies that provide grounds for moving from excessive use of chemicals to a more benign and organic effect on the quality of the products throughout the "grain – flour – bread" chain, is summarized.

The paper presents a contemporary view on organization of genes in the major histocompatibility complex, their protein products, and nomenclature of human leukocyte antigens.