The objective of this study was to investigate the genetic diversity of hexaploid wheat varieties of Uzbekistan breeding using simple sequence repeat (SSR) markers. These varieties are adapted to local conditions, and can be considered as the most important supplier of genetic resources for cultivation in Uzbekistan and other countries. Microsatellite markers are now most widely used and effective classes of DNA markers for genotyping, certification and classification of plant varieties. In this paper, genotyping results of 32 hexaploid wheat domestic varieties using 144 microsatellite primer pairs are presented. Microsatellite primer pairs were chosen from literature data and 36 primer pairs (from 144) gave polymorphic well-reproducible PCR-fragments. The individual SSR spectra differing in number of amplicons were obtained for each variety. A total number of 141 alleles for 36 microsatellite loci were detected. The number of alleles per locus ranged from 2 to 6, the mean number of alleles per locus (Na) was 3 alleles. For the studied genotypes group the effective number of alleles (ne) characterizing the loci by the allele frequency, varied from 1.7 to 4.8, the mean number of alleles per locus was 2.8. The expected heterozygosity (He) ranged from 0 to 0.792, averaging 0.626, in studied wheat population. The amplified fragment sizes ranged from 93 to 552 bp. The polymorphic index content (PIC) ranged from 0 to 0.758. A dendrogram was constructed using the alleles set of microsatellite loci, reflecting the phylogenetic differences of the studied hexaploid wheat varieties. It showed that Uzbekistan breeding varieties are divided into two main clusters, which may be evidence of their common origin.  A genetic formula has been developed for each Uzbek wheat variety. It can be used for identification, certification of these varieties, as well as for the selection of parental pairs in the wheat breeding programs.

As a component of functional nutrition, maize cultivars with “non-traditional” kernel composition (waxy, oilbearing, sugar, opaque, etc. phenotypic variants) are promising. Mutations in the waxy gene, which break down the structure and function of the enzyme for amylose biosynthesis, lead to a waxy (with a high content of amylopectin) endosperm formation. High variability of the waxy gene limits the use of microsatellite loci in marker associated selection of waxy maize genotypes. The increased frequency of gene rearrangements within the waxy locus facilitated the origination of many high-amylopectin corn lines carrying different SSR allelic variants. The purpose of this study was to evaluate the effectiveness of using waxy locus microsatellite sequences for identification and labeling of waxy maize genotypes. To this end, a complex of biochemical (calorimetry, bichromate method), molecular-genetic (SSR-PCR, capillary gel electrophoresis with fluorescent detection of fragments) and statistical (descriptive statistics, cluster analysis, χ2) analysis methods was used. Plant material used were 33 samples of corn kernels including mutant forms with a high content of amylose, amylopectin, short-chain starches, were kindly provided by VIR genetic collection (Russian Federation) and Maize Genetics Cooperation Stock Center (USA). The contents of starch, short-chain soluble carbohydrates, amylose, amylopectin in the grain of 33 maize samples were evaluated. Compositionally similar (to endosperm carbohydrates content) groups of samples were identified. They include 13 high-amylopectin samples carriers of waxy (wx) gene mutations and 20 samples with wild-type character (Wx). Molecular genetic screening of the collection included an analysis of the polymorphism of the microsatellite loci phi022, phi027, phi061 associated with the waxy gene sequence. Allelic composition of individual loci and their combinations were analyzed in relation to the accumulation of reserve carbohydrates in the kernel endosperm. Only the analysis of the phi022/phi027 combination or all three markers in the complex allows differentiating the wild Wx and mutant wx phenotypes of maize. It was shown that not the individual allelic polymorphisms of the phi022, phi027, phi061 loci are efficient for the markerassociated selection of high-amylopectin maize, but their unique combinations.

×Trititrigia cziczinii Tsvel. is a synthetic species obtained as a result of hybridization of different wheat and wheat- grass species. ×T. cziczinii has unique characteristics, as it is a perennial species, with the ability to grow after mowing, high adaptability, resistance to diseases and pests, high protein and gluten content in the grain. All this makes it a promising new crop for agriculture. The new species is a good object for fundamental research in the field of genetics, phylogeny and evolution of cereals (Poaceae). However, there were practically no genetic studies of ×T. cziczinii. The aim of this work was to study the genetic diversity of 24 representatives of two ×T. cziczinii subspecies (ssp. Submitans and ssp. Perenne). To estimate interspecific differences, 17 samples of other tribe Triticeae species (Triticum aestivum, Triticum durum, Agropyron glaucum and Agropyron elon gatum, as well as samples of Triticum-Agropyron and TriticumElymus hybrids) were included in the analysis. For the study, AFLP method (Amplified Fragment Length Polymorphism) was chosen, which allowed us to reveal a sufficiently high polymorphism level of the studied samples. The two primer/enzyme combinations (EcoRI-ACT/MseI-CCC, EcoRI-ACT/MseI-CTA) allow ed the iden tification of 227 fragments, 224 of them were polymorphic (98.68 %), and the level of intraspecific polymorphism of 24 ×T. cziczinii samples was 68.15 %. The iden tified fragments of AFLP spectra, specific for the ×T. cziczinii representatives and the studied wheatgrass species, can be the basis for creating markers that will detect introgressions of genetic material of the genus Agropyron in the T. cziczinii ge nome. Our results indicate a greater genetic relatedness of ×T. cziczinii to T. aestivum than to representatives of the genus Agropyron. According to the cluster analysis, representatives of ×T. cziczinii and varieties of bread wheat were combined into a single subcluster, within which the samples of two species form separate groups. At the same time, the evaluation of the intraspecific genetic diversity of ×T. cziczinii showed  no reliable differentiation of representatives of the subspecies Submitans and Perenne, which is probably due to uncertain genetic nature of perenniality, the main feature that divides these subspecies. The study of the unique ×T. cziczinii collection allowed us to obtain the first data on the genetics of the species, while previous studies were focused mainly on phenotypic and economically valuable traits. AFLP analysis used in this study showed high efficiency when working with less studied species, and its results are promising and useful for understanding the genetic structure of the new species (×T. cziczinii Tsvel.). 

Taxonomic and population genetic studies of the genus Spiraea (Rosaceae) species require new informative genetic markers. We screened 37 previously published heterologous oligonucleotide primer pairs for nuclear microsatellite loci and selected eight polymorphic and most reproducible of them for PCR multiplexing which substantially increases performance of routine mass genotyping. Three multiplex sets of 3, 3 and 2 loci, respectively, were developed and tested for ability to estimate the parameters of genetic variability and  population  structure in closely related species Spiraea ussuriensis, S. f lexuosa, S. chamaedryfolia representing seven natural populations of the Russian Far East and Siberia. Allele number ranged among loci from twelve (Spth20) to three. Among 41 alleles found, 7 were unique in some species/populations. Analysis of parameters of genetic variability in Spiraea spp. showed similar values of allele number per locus and observed heterozygosity among populations and slightly greater estimates of expected hete rozygosity in the samples of S. f lexuosa (NA = 2.387; HO = 0.387 ± ± 0.052; HE = 0.540 ± 0.055) as compared to S. ussuriensis (NA = = 2.781; HO = 0.385 ± 0.079; HE = 0.453 ± 0.072) and S. chamaedryfolia (NA = 2.875; HO = 0.331 ± 0.071; HE = 0.505 ± 0.069). The observed values of genetic polymorphism parameters indicate the average level of genetic diversity of the studied species typical to previous studies in Spiraea. About 19 % of the observed variability occurred among populations (FST = 0.191) while 81 % of the total genetic variation concentrated within the populations. The loci VS11, VS12, VS2, and VS6 contributed most to the observed differentiation. Nei genetic distances  between populations ranged from 0.049 to 0.585. Genetic differentiation patterns among studied populations based on allele frequencies of nuclear microsatellite loci correspond with their geographical location. Genetic composition of some samples contradicted with their provisional species identification.

At Pushkin and Pavlovsk Laboratories of the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR) a diverse collec tion of local apple cultivars is maintained. Some of the cultivars are widely used in breeding programs for their ecological plasticity, increased adaptation to abiotic stress and disease resistance, still there have been no large-scale studies of these local cultivars for fruit storage ability. Fruit softening during storage is an important problem for apple production. Retention of desirable firmness after prolonged storage is one of the key requirements for new apple cultivars. Expansin and ethy lene biosynthesis related genes are known to be involved in control of fruit softening in apple, and gene specific molecular markers have been reported. In this study the polymorphism and allelic configuration of ethylene and expansin biosynthesis related genes Md-ACS1, Md-ACO1 and Md-Exp7 involved in control of fruit softening in 87 local apple cultivars from VIR Collection of Plant Genetic Resources were analyzed. PCR markers Md-ACS1, Md-ACO1 and SSR-marker Md-Exp7 were used in the study. The allele frequencies in the collection generally coincided with the data from previous studies. Md-ACS1 allele 2 associated with reduced ethylene production was found only in three local cultivars, while all the studied local cultivars were heterozygous for the Md-ACO1 locus, as well as most modern Russian apple cultivars. Half of the studied local cultivars were heterozygous for Md-Exp7 (198 : 202). Thirteen local cultivars with rare Md-Exp7 alleles (206, 210 and 212) were detected. No association was found between the Md-Exp7 genotype and the cultivars’ maturation time. The obtained results can be used for additional evaluation of the cultivars’ potential for breeding.

Antimicrobial peptides (AMPs) are important components of defense system in both plants and animals. They represent an ancient mechanism of innate immunity providing rapid first line of defense against pathogens. Plant AMPs are classified into several families: thionins, defensins, nonspecific lipid-transfer proteins, hevein- and knottin-type peptides, hairpinins and macrocyclic peptides (cyclotides). The review focuses on the thionin family. Thionins comprise a plant-specific AMP family that consists of short (~5 kDA) cysteine-rich peptides containing 6 or 8 cysteine residues with antimicrobial and toxic properties. Based on similarity in amino acid sequences and the arrangement of disulphide bonds, five structural classes of thionins are discriminated. The three-dimensional structures of a number of thionins were determined. The amphipathic thionin molecule resembles the Greek letter Г, in which the long arm is formed by two antiparallel α-helices, while the short one, by two parallel β-strands. The residues responsible for the antimicrobial activity of thionins were identified. Thionins are synthesized as precursor proteins consisting of a signal peptide, the mature peptide region and the C-terminal prodomain. Thionins protect plants from pathogenic bacteria and fungi acting directly on the membranes of microorganisms at micromolar concentrations, although their precise mode of action remains unclear. In addition to plant pathogens, thionins inhibit growth of a number of human pathogens and opportunistic microorganisms, such as Candida spp., Saccharomyces cerevisiae, Fusarium solani, Staphylococcus aureus and Escherichia coli. Thionins are toxic to different types of cells including mammalian cancer cell lines. Transgenic plants expressing thionin genes display enhanced resistance to pathogens. A wide range of biological activities makes thionins promising candidates for practical application in agriculture and medicine.

The aim of this research is to develop for the Russian Federation Non-Cher nozem Zone competitive prototypes of winter wheat cul tivars with several genes for resistance to stem rust (in clu ding race Ug99) based on new sources of resistance with the use of molecular markers. The individual plants and then lines of winter common wheat with several effective genes for resistance to race Ug99 of stem rust were selected by means of marker assistant selection out of hybrid combinations from the crossing of new donors of resistance to this dangerous disease. The development of initial material was based on the use of new sources of resistance to race Ug99 of stem rust from VIR and “Arsenal” collections. Three accessions of winter wheat (wheat-aegi lops-rye line 119/4-06rw, cv. Donskaya Polukarlikovaya, line GT 96|90 from Bulgaria) and one accession of spring wheat (line 113/00i-4 with genetic material from Aegilops triuncialis), which supplemented and contrasted each other in such economically valuable features as plant height, number of days before heading, resistance to powdery mildew and leaf rust, were selected for hybridization and backcrossing. To accelerate the breeding process, resistant genotypes with Sr genes were selected with the use of molecular markers. As a result the lines of winter common wheat with a set of economically valuable features and the presence of two-four genes for resistance to stem rust in homozygote state were created. The spectrum of the stem rust gene combinations in the created lines differs from the gene combinations in the parental accessions involved in the crossing and is associated with the direction of the selections conducted by the marker assisted selection method. We discovered more than 20 different combinations of the Sr2, Sr22, Sr31, Sr32, Sr36, Sr39, Sr40 and Sr47 genes in winter wheat lines. The combination of Sr22 and Sr32 in homozygote state was most often found. The genotypes with a set of economically valuable features approximating or surpassing the standard cultivar of winter wheat Moskov skaya 39 were selected for further testing in breeding nurseries of the Moscow region. The developed initial material is intended for use in selection of winter wheat cultivars resistant to stem rust in different grain-sowing regions of the Russian Federation. This will serve as a barrier for spread of new races of Puccinia graminis and will raise the resistance of selected cultivars to local populations of stem rust.

In this study, naturally and artificially inoculated winter wheat varieties were studied with respect to their productivity and resistance to Fusarium head blight (FHB). We used the following set of disease assessment parameters: the percentage of visually and latent Fusarium-damaged grains (FDG); the DNA content of Fusarium fungi; the productivity of inoculated plants compared with non-inoculated plants; and the amount of mycotoxins in the grain. In case of naturally infected grains, the average FDG was found to be about 6.1 % (range of 0–15 %). The amount of DNA of Fusarium graminearum was found to be in the range of (1.1–42.7) × 10–5 ng/ng wheat DNA. The mycotoxin deoxynivalenol (DON) was detected in 15 samples of grain from plants that were grown under natural infection. The maximum DON amount was found to be 420 μg/kg. Fumonisin B1 (FB1) was not be detected in naturally infected grain. In case of artificially inoculated plants, the average FDG was found to be 25.8 % (2–54 %). The amount of F. graminearum DNA was found to be significantly higher (4.24– 49.8) × 10–3 ng/ng than it was detected in grain of non-inoculated plants. The wheat varieties inoculated with F. graminearum contained DON in high amounts from 20255 to 79245 μg/kg. Furthermore, a significant amount of FB1 was detected in all wheat varieties in the range of 980–20326 μg/kg. Among the analysed wheat varieties, Adel was characterized to be the most resistant to fungal infection as well as to the contamination by mycotoxins. Antonina, Lebed and Pamyat varieties were classified more relatively resistant than that of other varieties, and Utrish variety was found to be the most susceptible to FHB. The similar resistance of wheat varieties against F. graminearum and F. verticillioides infection was recorded, and the interactions between the fungi during the colonization of grain were shown.

The main objectives in potato breeding are increasing yield abilities and improving resistance to numerous pathogens and pests. Among them, the late blight caused by the Phytophthora infestans oomycete is one of the most destructive potato diseases both in Russia and worldwide. Wild relatives of cultivated potato are traditionally used in breeding as the source of valuable R genes conferring resistance to pathogens. Of particular interest are Mexican wild species because Mexico is the centre of origin and diversity of P. infestans and at the same time, it is the centre of potato species diversity.  Mexican wild potato species S. bulbocastanum and S. stoloniferum are an important source of the R genes conferring broad-spec trum resistance against various isolates of P. infestans (Rpi-blb1,  Rpi-blb2, Rpi-sto1). Recently these genes have been transferred into cultivated potato gene pool using the cisgene  approach. At the same time there is a high probability of finding geno types with the Rpi-sto1 gene (functional homologues of  Rpi-blb1) among conventionally bred varieties because for about 40 years S. stoloniferum has been used in breeding as a source of the Rysto and Ry-fsto genes of the extreme resistance to the most important viral pathogen PVY. In this study 188 potato varieties bred in Russia and in near-abroad countries were screened for the presence of six gene-specific markers of the RB/Rpi-blb1 =  Rpi-sto1 and Rpi-blb2 genes conferring broad-spectrum resistance against P. infestans, and for the markers linked to the Rysto and Ry-fsto genes conferring extreme resistance to PVY. In addition, a marker for detecting male sterile mitochondrial DNA type gamma derived from S. stoloniferum was used. The genotypes selected through the molecular markers were divided into four groups: (A) 13 PVY resistant varieties carrying diagnostic markers of the Rysto, Ry-fsto genes and having sterile mt-type gamma; (B) four varieties possessing mt-type gamma and not having the markers of the R genes introgressed from S. stoloniferum; (C) eight genotypes carrying five gene-specific markers for the RB/Rpi-blb1/= Rpi-sto1; (D) the rest 166 (86.9 %) varieties not possessing any of the diagnostic markers associated with the S. stoloniferum genetic material. The sequences of the Rpi-sto1- and BLB1 F/R-amplicons were identical in all the genotypes of group ‘C’ and showed respective 99 % and 100 % similarity to the corresponding fragments of the Rpi-sto1 and Rpi-blb1 genes from the GenBank database. Among the genotypes of group ‘C’ various mt-types were detected, and some of them were male fertile.

Downy mildew is one of the most common fungal diseases of the vine, caused by Plasmopara viticola. An effective way to control the spread of the pathogen is to cultivate resistant varieties. Cultivars of Vitis vinifera, being the basis of high-quality viticulture, practically do not possess genetic resistance to P. viticola, so screening for resistance donors is an important stage in breeding. One of the major resistance loci to downy mildew, the Rpv3 gene, was identified in the genotype of a complex interspecific hybrid of grapes Bianca. Later, it was found that this gene had seven haplotypes of resistance inherited from North American grape species, and that it was possible to identify the allelic status of the gene using DNA-markers UDV305, UDV737. However, only two haplotypes can be combined in one diploid form. To determine the Rpv3 gene in the grape gene pool we, using these markers, studied 35 different genotypes of grapevines, most of which are interspecies cultivars. Three varieties with known allelic status of the Rpv3 gene (Dunavski lazur, Noah, Seyve Villard 12-375) were included in the study as reference genotypes. The genotypes were studied through polymerase chain reaction with separation of amplification products by capillary electrophoresis in automatic genetic analyzer ABI Prism 3130. In the studied grape cultivars DNA marker analysis indentified the Rpv3 gene in sixteen genotypes of interspecific origin, including haplotype Rpv3299-279 found in twelve varieties, Rpv3321-312 – in three, and haplotype Rpv3null-271 – in one variety. Seyve Villard 12-375 turned out to be the donor of resistance gene in the most of the genotypes carrying Rpv3 in this study. The obtained data can be useful in selection of mildew resistant grape varieties and screening for hybridization pairs.

For a targeted search of initial breeding material for the quality of soybean seeds, it is necessary to know the patterns of the dependence of the corresponding seed characters on the weather and climatic conditions in a particular region. Global climatic change, the concretization of which is relevant, has a share in this dependence. Thus, the aim of this work was to identify the relationship between the variability of protein and oil content in soybean seeds with climatic parameters in the North Caucasus as well as trends in this variability over a long time period. The study of 1 442 soybean accessions from VIR collection in the Krasnodar region during 1987–2015 had been carried out and the tendencies of the variability of protein and oil content in seeds in this environment were estimated. The regression analysis in differences with forward stepwise selection of variables has been used to construct models for the dependence of the protein and oil content on generalized agrometeorological indices. During 1987–2015, for the period with temperatures above 10 °C, the sums of active temperatures increased by 218 °C/10 years and precipitation decreased by 20.9 mm/10 years. In the dynamics of protein content, a trend has been revealed as an increase by 2.5 % over 10 years, while there is no reliable trend in oil content. The maximum average mean of oil content and the smallest protein were in the middle-maturing accessions (22.2 and 38.8 %), and a relatively high protein content was detected, on average, in the early- (21.6 and 40.0 %) and late-maturing (20.2 and 39.9 %) varieties. The protein content had been increasing with a growth of the duration of the period with temperatures above 22 °C and decreasing with a raise in precipitation over a period of temperatures above 18 °C. The accumulation of oil in seeds was promoted by an increase of the hydrothermal coefficient over the period with temperatures above 19 °C, and, in late-maturating varieties, prevented by a prolonged autumn period with temperatures below 15 °C. Long-term growth in protein content is due to both climatic change and genetic improvement of varieties.

One of the most important problems of modern neurobiology and medicine is an understanding of the mechanisms of normal and pathological behavior of a person. Aggressive behavior is an integral part of the human psyche. However, environmental risk factors, mental illness and somatic diseases can lead to increased aggression to be the biological basis of antisocial behavior in a human society. An important role in development of aggressive behavior belongs to the hereditary factors that may be linked to abnormal functioning of neurotransmitter systems in the brain yet the underlying genetic mechanisms remain unclear, which is due to a large number of single nucleotide polymorphisms, insertions and deletions in the structure of genes that encode the components of the neurotransmitter systems. The most studied candidate genes for aggressive behavior are serotonergic (TPH1, TPH2, HTR2A, SLC6A4) and dopaminergic (DRD4, SLC6A3) system genes, as well as the serotonin or catecholamine metabolizing enzyme genes (COMT, MAOA). In addition, there is evidence that the hypothalamic-pituitary system genes (OXT, OXTR, AVPR1A, AVPR1B), the sex hormone receptors genes (ER1, AR), neurotrophin (BDNF) and neuronal apoptosis genes (CASP3, BAX) may also be involved in development of aggressive behavior. The results of Genome-Wide Association Studies (GWAS) have demonstrated that FYN, LRRTM4, NTM, CDH13, DYRK1A and other genes are involved in regulation of aggressive behavior. These and other evidence suggest that genetic predisposition to aggressive behavior may be a very complex process.

Carotid paragangliomas (CPGLs) are rare neuroendocrine tumors that arise from paraganglionic tissue of the carotid body localizing at the bifurcation of carotid artery. These tumors are slowly growing, but occasionally they become aggressive and metastatic. Surgical treatment remains high-risk and extremely challenging; radiation and chemotherapy are poorly effective. The study of molecular pathogenesis of CPGLs will allow developing novel therapeutic approaches and revealing biomarkers. Previously, we performed the exome sequencing of 52 CPGLs and estimated mutational load (ML). Paired histologically normal tissues or blood were unavailable, so potentially germline mutations were excluded from the analysis with strong filtering conditions using 1000 Genomes Project and ExAC databases. In this work, ten genes (ZNF717, CDC27, FRG2C, FAM104B, CTBP2, HLA-DRB1, HYDIN, KMT5A, MUC3A, and PRSS3) characterized by the highest level of mutational load were analyzed. Using several prediction algorithms (SIFT, PolyPhen-2, MutationTaster, and LRT), potentially pathogenic mutations were identified in four genes (CDC27, CTBP2, HYDIN, and KMT5A). Many of these mutations occurred in the majority of cases, and their mutation type was checked using exome sequencing data of blood prepared with the same exome enrichment kit that was used for preparation of exome libraries from CPGLs. The majority of the mutations were germline that can apparently be associated with annotation errors in 1000 Genomes Pro ject and ExAC. However, part of the mutations identified in CDC27, CTBP2, HYDIN, and KMT5A remain potentially pathogenic, and there is a large body of data on the involvement of these genes in the formation and progression of other tumors. This allows considering CDC27, CTBP2, HYDIN, and KMT5A genes as potentially associated with CPGL pathogenesis and requires taking them into account in further investigations. Thus, there is a necessity to improve the methods for identification of cancer-asso ciated genes as well as pathogenic mutations. 

Small and unique Buryat and Altai cattle breeds of TuranoMongolian origin are well adapted to harsh conditions of the continental climate to be their habitat. However, the population-genetic structure of the breeds has been poorly studied. This paper presents the results of analysis of polymorphisms GH1 (AC_000176.1: BTA 19, exon 5, rs41923484, g.2141C>G, L127V), GHR (AC_000177.1: BTA 20, exon 10, rs109300983, g.257A>G, S555G) and PRL (AC_000180.1: BTA 23, exon 3, g.35108342A>G) in the samples of Buryat cattle breed of Russia, China and Mongolia, and indigenous Altai cattle breed (Russia) that belong to TuranoMongolian cattle. The Russian sample of Buryat breed was differentiated from the Mongolian sample based on pairwise G-test and FST values for the PRL-RsaI polymorphism and from the Chinese sample – based on pairwise G-test values for the GH1-AluI polymorphism. All the three samples of Buryat breed clearly differed from the sample of Altai breed based on pairwise G-test and FST values for the GHR-AluI polymorphism as well as on the base of FST values for the joint polymorphism of the three genes. Nei’s genetic distances calculated from the three gene polymorphisms also confirmed the difference between the two breeds. The results of AMOVA demonstrated that GHR gene variability (16 %) gave the largest contribution to the differentiation that was confirmed by FST values (0.12–0.27). The STRUCTURE software enabled us to reveal four clusters, with a specific ratio for each sample, in the Chinese and Mongolian samples of Buryat breed, and in the sample of Altai breed, while the Russian sample of Buryat breed had only three clusters. The differences within the breed level were determined based on the GH1-AluI and PRL-RsaI polymorphisms, while at the inter-breed level – based on the GHR-AluI polymorphism. Linkage disequilibrium analysis demonstrated significant linkage of the following pairs of genes in the Buryat breed: GH1-GHR, GH1-PRL, GHR-PRL.

Conservation of local cattle genetic resources is an important strategy for achieving Russia’s food security. During last decades, in the Russian Federation, local livestock populations were either crossbred or replaced by highly productive imported breeds, which led to a loss of the major part of original breeds identities. The objective of our study was to identify genetic differences between the populations of Kholmogor and Black-and-white cattle with varying degrees of admixture with the Holstein breed. The aforementioned breeds were studied using their whole-genome single nucleotide polymorphism (SNP) genotypes. The Kholmogor breed was subdivided into three groups: purebred (KHLM, n = 3), admixed with Holsteins (KHLM-HLST, n = 4) and representatives of old-type breed (KHLM-INTA, n = 15). Blackand-white was subdivided into four groups: purebred (BLWT, n = 9), with a low (BLWT-75, n = 8) and a high (BLWT-HLST, n = 10) level of admixture with Holstein, and represented by archival samples from the 1970s and 1980s (BLWT-OLD, n = 15). The Holsteins genetic profiles (HLST, n = 27) were taken as a comparison group. PLINK 1.07, Admixture 1.3, SplitsTree 4.14.6 and R package StAMPP were used to infer genetic relationship between the studied groups. After quality control, 29 688 SNPs were selected for analysis. Multidimensional scaling (MDS), Admixture analysis and a dendrogram constructed using the Neighbor-Net method, revealed the presence of three clusters belonging to the Kholmogor, Black-and-white and Holstein breeds. The first one included KHLM and KHLM-INTA, the second – BLWT and BLWT-OLD, and the third – HLST, KHLM-HLST and BLWT-HLST. The BLWT-75 samples were placed between HLST and BLWT. Thus, our results showed that currently the populations of native cattle breeds with valuable genotypes still exist. The populations with a high level of admixture with Holsteins could be considered neither as the Kholmogor nor as Blackand-white breeds, and would rather be referred as the Holstein breed of local breeding.