Allozyme variability in populations of trout (<Emphasis Type="Italic">Salmo trutta</Emphasis>) from the rivers of Iran

For the first time, an analysis was carried out of allozyme variability in trout (Salmo trutta) from three rivers of Iran. We studied 23 gene loci coding enzymes: glycerol-3-phosphate dehydrogenase (G3PDH), aspartate aminotransferase (AAT), malate dehydrogenase (MDH), lactate dehydrogenase (LDH), creatine kinase (CK), malic enzyme [NADP-dependent MDH] (MEP), superoxide dismutase (SOD), esterase (EST), and esterase D (EST-D). The obtained data demonstrate the similarity between the trout samples from different rivers of Iran according to genetic characteristics. Taking into account the differences by allozyme markers of allele frequencies and allele composition of some loci, we should expect that Iranian trout diverges significantly in genetics from the other trout populations of the Caspian Sea.     

Molecular genetic characteristic of dinucleotide microsatellite loci in parthenogenetic lizards <Emphasis Type="Italic">Darevskia unisexualis</Emphasis>

In the present study, the first molecular genetic investigation of dinucleotide (GT) _n microsatellite loci in parthenogenetic lizards Darevskia unisexualis was performed. New polymorphic locus, Du214, (GenBank Ac. No. EU252542) was identified and characterized in detail. It was demonstrated that allele of this locus differed in the size and structure of microsatellite locus, as well as in point mutations, the combinations of which enabled the isolation of stabile fixed double nucleotide substitutions A-A (alleles 2 and 4) and G-T (alleles 1, 3, 5, and 6). Double nucleotide substitutions described were also identified in the orthlogous loci of the parental species genomes, D. raddei (G-T) and D. valentine (A-A). Based on the analysis of allele distribution pattern at this locus in all populations of parthenospecies D. unisexualis, mathematic model was elaborated and realized. Using this model, frequencies of allelic variants for all populations of the species of interest were calculated and population genetic structure of D. unisexualis was characterized. Genetic contribution of each population to the species gene pool was determined. The data obtained demonstrated that microsatellite variation was one of the factors of clonal and genetic diversity of a parthenospecies.     

Polymorphism of Y-chromosomal microsatellites in Russian population from Southern Federal district of the Russian Federation

Haplotype frequencies and allele distributions at 11 STR loci of the Y chromosome were evaluated in 180 unrelated individuals from Russian population of Southern Federal district of the Russian Federation (Rostov oblast, Krasnodar krai, and Stavropol krai). Among 153 Y-chromosomal haplotypes discovered, 62 were unique. In the sample of Russian population, the most frequent haplotype (frequency of 5.56%) was 16-11,14-13-30-25-11-11-13-14-11-10 (for the loci DYS19, DYS385a,b, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, and DYS439, respectively). Despite the high diversity of Y-chromosomal haplotypes in the Russian populations from the south of Russia (the h value was 0.997, 0.995, and 0.994 in Rostov, Krasnodar, and Stavropol samples, respectively), analysis of molecular variance (AMOVA) showed the absence of differentiation between the populations (Φ_ST = 0.1%, P = 0.36). Comparative differentiation analysis performed for 13 Russian populations from the European part of Russia pointed to low among-population differentiation in Y-chromosomal lineages (Φ_ST = 0.52%, P = 0.03).     

A mutation in <Emphasis Type="Italic">KIR3DS1</Emphasis> that results in truncation and lack of cell surface expression

The KIR gene cluster exhibits a high degree of polymorphism in terms of gene content as well as allelic polymorphism, and data suggest that it is evolving rapidly. The KIR3DL1 locus is one of the most polymorphic loci within this cluster and is unique in that it encodes an activating receptor KIR3DS1, as well as multiple inhibitory KIR3DL1 allotypes. Because KIR3DS1 has been implicated in a number of diseases, we tested for the presence of KIR3DS1 variants that might affect its expression and activating capacity. Preliminary FACS analysis indicated that indeed some individuals with the KIR3DS1 allele showed no cell surface expression of the molecule. Sequencing analysis identified a variant with a complex deletion/substitution mutation in exon 4 (which encodes the D1 extracellular domain), resulting in a premature stop codon. We subsequently genotyped 3,960 unrelated individuals and determined the frequencies of this allele across geographically distinct world populations. The data indicate that the null KIR3DS1 allele is uncommon, arose on a single haplotype, and spread across geographically distinct populations.     

Glutathione-S-transferase gene polymorphism in Russian populations of European part of Russia

Distribution of several widespread, extensively studied polymorphic variants of genes of the cytosol glutathione-S-transferase subfamily (GSTA1, GSTM1, GSTM3, GSTP1, and GSTT1) has been studied in samples from Russian populations of European Russia, as well as Komi and Yakut populations used for comparison. Analysis of the GSTP1 and GSTM3 polymorphisms has not revealed significant differences in the distribution of alleles of the loci, including two-site GSTP1 haplotypes, in most Russian populations and between Komi populations. Only in the Yakut sample have a significant difference been found with respect to these loci in each pairwise comparison. Regarding the GSTT1 and GSTA1 genes, in addition to differences between the Yakut population and all other populations with respect to the GSTA1 gene, it has been found that the frequencies of the GSTT1 0/0 deletion genotype and GSTA1 ?69T allele in the Russian sample from Mezen’ (Arkhangel’sk oblast) are substantially lower than in other Russian populations and Komi populations. The significance of these differences has been confirmed by tests for heterogeneity of the entire pool of Russian populations.     

Genetic structure of populations and natural hybridization between <Emphasis Type="Italic">Dactylorhiza salina</Emphasis> and <Emphasis Type="Italic">D. incarnata</Emphasis> (Orchidaceae)

The results of studying the polymorphism and genetic structure of populations of D. salina and D. incarnata growing in Zabaykalsky krai and Buryatia are represented according to the data of allozyme analysis of eight genetic loci (PGI, NADHD, SKDH, GDH, PGM, DIA, ADH, and IDH). The specificity of the allelic structure of loci SKDH, PGM, and IDH is established, for which D. salina and D. incarnata reliably differ from each other. It is shown that interspecies introgressive hybrid complexes with different genetic structures were formed in Transbaikalia. Places of mass growth of D. incarnata were observed to have single plants of D. salina, the interspecies hybrids of the first and subsequent generations. Places of mass growth of D. salina were observed to contain only the hybrids that are not hybrids of the first generation. They were heterozygous not for three loci with differentiating alleles of both parents, SKDH, PGM, and IDH, but for only one of them. The degree of genetic differentiation among five populations of D. salina was on average 7.5% and that of D. incarnata was 7.1%, which in accordance with Wright’s estimation relates to mean values. The average value of FST for all studied populations of the two related species of the genus Dactylorhiza was 0.478, indicating a very high degree of genetic differentiation between D. salina and D. incarnata growing in Transbaikalia. The greatest differences between the species are for the allelic structure of loci SKDH, PGM, and IDH (FST was equal to 0.705, 0.976, and 0.762, respectively). Analysis of molecular variance (AMOVA) showed that populations of D. salina and D. incarnata in the zone where their ranges in Zabaykalsky krai and Buryatya overlap have essential differences both for the variation of alleles frequencies of eight loci (71%, d.f. = 9) and for the variability of genotypes (61%, d.f. = 9). Despite the fact that D. salina and D. incarnata explicitly share a gene flow as a result of interspecies hybridization, the genetic differentiation of populations of these related species remains at a high level.     

Gene polymorphism of the renin-angiotensin system in six ethnogeographic regions of Belarus

The insertion/deletion polymorphism of the angiotensin-converting enzyme gene (ACE) and the T174M polymorphism of the angiotensinogen gene (AGT) have been studied in six ethnogeographic regions of Belarus. Significant intrapopulation differences in ACE genotype frequencies have been found for the northern and eastern regions (the Dvina and Dnepr basins, respectively). Significant differences in the AGT genotype frequencies have been found between populations of the Dnepr basin and populations of all other Belarusian regions. The allele and genotype frequencies of the genes studied in the Belarusian population and populations of other regions of the world have been compared. The frequencies of the insertion (I) and deletion (D) alleles of the ACE gene in the Belarusian population are 50.7 and 49.3%, respectively, which is similar to these frequencies in European countries. The frequency of the M allele of the AGT gene in Belarus is 16.6%, which is higher than its frequency in populations of European, African, and Asian origins.     

A new design without control population for identification of gastric cancer-related allele combinations based on interaction of genes

Objective

The purpose of this study was to develop a novel approach without control population to examine the relationship between the presence of specific allele combinations at different loci with the onset of gastric cancer.

Methods

DNA samples were collected from patients with gastric cancer. Alleles from short tandem repeat loci were determined using the STR Profiler Plus PCR amplification kit (15 STR loci). The observed and expected frequencies of specific allele combinations were calculated; statistically significant allele combinations were identified by comparing the observed frequency with the expected frequency. The age at disease onset of patients carrying a specific allele combination was further analysed; allele combinations related to the gastric cancer were effectively identified from the large number of possible allele combinations by cross-validation of the 2 sets of analytical results.

Results

A total of 2209 pairwise combinations were obtained by computer counting, of which 11 pairs of genes showed significant differences between the observed and expected frequencies (p < 0.05). The p value for the cross-validation was also less than 0.05 for 2 pair of alleles (D8S1179-16 and D5S818-13; D2S1338-23 and D6S1043-11).

Conclusion

Gastric cancer onset may be associated with these allele combinations. The new methodology without control group will enable additional discoveries pertaining to the relationship between specific allele combinations at different loci and the onset of complex diseases.     

Genetic structure of the populations of <Emphasis Type="Italic">Dactylorhiza ochroleuca</Emphasis> and <Emphasis Type="Italic">D. incarnata</Emphasis> (Orchidaceae) in the area of their joint growth in Russia and Belarus

We carried out an allozyme analysis to investigate polymorphism and genetic structure of the populations of D. incarnata and D. ochroleuca in regions of their joint growth in Russia and Belarus. We found that D. ochroleuca individuals in the populations of the Urals and Siberia, which are distant fragments from the main range of the species, do not differ significantly from individuals within the main part of the area (Belarus) on the basis of the allelic composition of eight gene loci. We revealed that D. ochroleuca and D. incarnata are differentiated by different alleles of the GDH locus. Thus, we established a genetic marker suitable to distinguish these closely related taxa. In addition to the GDH locus, D. ochroleuca and D. incarnata in the places of their joint growth, differ in the allelic structure of the PGI and NADHD loci. D. incarnata from the Urals and Siberia were polymorphic for both loci, and individuals from Belarus were polymorphic for one locus (PGI). In contrast, all D. ochroleuca individuals growing in sympatric populations with polymorphic D. incarnata were homozygous for the same alleles. Thus, comparison of the genetic structure of D. ochroleuca and D. incarnata points to the existence of a genetic isolation and a functioning isolation mechanism even under conditions of their joint growth. We found that the GDH locus in D. incarnata is polymorphic only in populations which grow together with D. ochroleuca, with exception a few examples. Thus, we conclude that variability of the GDH locus in D. incarnata is associated with hybridization with D. ochroleuca.     

Genetic structure of the Russian populations of <Emphasis Type="Italic">Pyrenophora tritici-repentis</Emphasis>, determined by using microsatellite markers

The population genetic structure of plant pathogenic fungus Pyrenophora tritici-repentis was examined using microsatellite (SSR) markers. According to the geographical origin of the pathogen populations, they were designated as North Caucasian (S, 33 isolates), northwest (Nw, 39), and Omsk (Om, 43). The populations were analyzed at the nine most polymorphic SSR loci, at which 75 alleles were identified. To characterize the genetic variation within and between populations, the AMOVA algorithm as implemented in the Arlequin v. 3.5 software program was used. The number of alleles per locus ranged from 5 to 12 and their sizes varied within the range from 180 to 400 bp. The mean gene diversity at SSR loci was high for all populations (H = 0.58–0.75). The populations were considerably different in the frequencies of individual alleles of the SSR loci. Most isolates in the populations were represented by unique haplotypes. The within-population variation of the isolates at molecular markers was 86.4%; among the populations, 13.6%. Substantial interpopulation differences were found between the Om and S (F_st = 0.16) and between the Om and Nw (F_st = 0.20) populations, whereas between the S and Nw populations, these differences were small (F_st = 0.05). Thus, it was demonstrated that the population of P. tritici-repentis from Omsk oblast had the independent status of the geographical population; northwest and North Caucasian populations differed in the allelic diversity of SSR loci, and despite the low F_st value (0.05), they also belonged to independent geographical populations.     

Hordein locus polymorphism of cultivated barley (<Emphasis Type="Italic">Hordeum vulgare</Emphasis> L.) in Turkey

Starch gel electrophoresis has been used to study the polymorphism of hordeins encoded by the Hrd A, Hrd B, and Hrd F loci in 93 landrace specimens of barley assigned to 17 ancient provinces located in modern Turkey. Forty-five alleles of Hrd A with frequencies of 0.11–29.34%, 51 alleles of Hrd B with frequencies of 0.11–8.07%, and 5 alleles of Hrd F with frequencies of 0.75–41.29% have been detected. Cluster analysis of the matrix of allele frequencies has demonstrated that barley populations from different old provinces of Turkey are similar to one another. Cluster structure of local barley populations has been found, most populations (82%) falling into three clusters. The first cluster comprises barley populations from six provinces (Thracia, Bithynia, Pontus, Lydia, Cappadocia, and Armenia); the second cluster, populations from five provinces (Paphlagonia, Galatia, Lycaonia, Cilicia, and Mesopotamia); and the third one, populations from three provinces (Phrygia, Karia, and Lycia). Barley populations from Mysia, Pamphlya, and Syria do not fall in any cluster.     

Genetic differentiation among natural populations of the lizard complex <Emphasis Type="Italic">Darevskia raddei</Emphasis> as inferred from genome microsatellite marking

The article presents the genetic parameters of the populations of lizards of the Darevskia raddei complex (D. raddei nairensis and D. raddei raddei) and the populations of D. valentini calculated on the basis of the analysis of variability of 50 allelic variants of the three nuclear genome microsatellite-containing loci of 83 individuals. It was demonstrated that the F_st genetic distances between the populations of D. raddei nairensis and D. raddei raddei were not statistically significantly different from the F_st genetic distances between the populations of different species, D. raddei and D. valentini. At the same time, these distances were statistically significantly higher than the F_st distances between the populations belonging to one species within the genus Darevskia. These data suggest deep divergence between the populations of D. raddei raddei and D. raddei nairensis of the D. raddei complex and there arises the question on considering them as separate species.     

Developing forensic reference database by 18 autosomal STR for DNA identification in Republic of Belarus

For the Republic of Belarus, development of a forensic reference database on the basis of 18 autosomal microsatellites (STR) using a population dataset (N = 1040), “familial” genotypic dataset (N = 2550) obtained from expertise performance of paternity testing, and a dataset of genotypes from a criminal registration database (N = 8756) is described. Population samples studied consist of 80% ethnic Belarusians and 20% individuals of other nationality or of mixed origin (by questionnaire data). Genotypes of 12346 inhabitants of the Republic of Belarus from 118 regional samples studied by 18 autosomal microsatellites are included in the sample: 16 tetranucleotide STR (D2S1338, TPOX, D3S1358, CSF1PO, D5S818, D8S1179, D7S820, THO1, vWA, D13S317, D16S539, D18S51, D19S433, D21S11, F13B, and FGA) and two pentanucleotide STR (Penta D and Penta E). The samples studied are in Hardy–Weinberg equilibrium according to distribution of genotypes by 18 STR. Significant differences were not detected between discrete populations or between samples from various historical ethnographic regions of the Republic of Belarus (Western and Eastern Polesie, Podneprovye, Ponemanye, Poozerye, and Center), which indicates the absence of prominent genetic differentiation. Statistically significant differences between the studied genotypic datasets also were not detected, which made it possible to combine the datasets and consider the total sample as a unified forensic reference database for 18 “criminalistic” STR loci. Differences between reference database of the Republic of Belarus and Russians and Ukrainians by the distribution of the range of autosomal STR also were not detected, corresponding to a close genetic relationship of the three Eastern Slavic nations mediated by common origin and intense mutual migrations. Significant differences by separate STR loci between the reference database of Republic of Belarus and populations of Southern and Western Slavs were observed. The necessity of using original reference database for support of forensic expertise practice in the Republic of Belarus was demonstrated.     

Current state of the genetic polymorphism in spring barley (<Emphasis Type="Italic">Hordeum vulgare</Emphasis> L.) from Russia assessed by the alleles of hordein-coding loci

Starch gel electrophoresis was performed to study the polymorphism of hordeins encoded by the Hrd A, Hrd B, and Hrd F loci in 211 varieties of spring barley. For 41 of these varieties, the genetic formulas were established for the first time. In the two samples of varieties, the comparative analysis of allelic diversity and allele frequencies of hordein-coding loci was carried out. The first sample consisted of 101 spring barley varieties approved for the use on the territory of the Russian Federation in 1999, while the second sample included 160 spring barley varieties that were approved in 2014; 49 of these varieties were common for both samples. It is demonstrated that the current tendency to reduction of the proportion of heterogeneous spring barley varieties is mainly due to the introduction of foreign varieties homogeneous for the hordein-coding loci. At the same time, there is an increase in polymorphism of hordein-coding loci in modern spring barley varieties. The number of alleles for the Hrd A locus increased by five alleles, and for the Hrd B locus, by nine alleles. Along with the alleles recorded earlier in barley landrace populations and varieties bred in 20th century, three novel alleles of the Hrd A locus and four alleles of the Hrd B locus were identified. The number of alleles of the Hrd F locus remained unchanged (four), and the changes in their frequencies were small. At the same time, the changes in frequency observed for some alleles of the Hrd A and Hrd B loci were statistically significant. All newly identified alleles of hordein-coding loci were found with low frequencies (from 0.003 to 0.006), so despite the increased number of alleles, no statistically significant increase in genetic diversity in terms of μ and PIC indices was observed.     

Polymorphism of chloroplast microsatellite DNA loci in Russian potato cultivars

The cpSSR method was for the first time used to analyze the plastome in 29 Russian potato Solanum tuberosum cultivars. The informativeness coefficient H and the allele variability of the NTCP6, NTCP8, and NTCP9 loci were determined. In total, 14 allelic variants of the microsatellite cpDNA loci were identified. The NTCP8 and NTCP9 cpSSR displayed the highest allele polymorphism in the cultivars examined. A cultivar-specific haplotypes of the chloroplast genome were observed for 20 out of 29 cultivars.     

Y-chromosome polymorphisms of the domestic Bactrian camel in China

Single-nucleotide polymorphisms (SNPs), microsatellites and copy number variation (CNV) were studied on the Y chromosome to understand the paternal origin and phylogenetic relationships for resource protection, rational development and utilization of the domestic Bactrian camel in China. Our sample set consisted of 94 Chinese domestic Bactrian camels from four regions (Inner Mongolia, Gansu, Qinghai and Xinjiang), we screened 29 Y-chromosome-specific loci for SNPs, analysed 40 bovine-derived microsatellite loci and measured CNVs of HSFY and SRY through Sanger sequencing, automated fluorescence-based microsatellite analysis and quantitative real-time PCR, respectively. A multicopy gene, SRY, was first found, and sequence variation was only detected in SRY in a screen of 29 loci in 13 DNA pools of individual camels. In addition, a TG repeat in the USP9Y gene was identified as the first polymorphic microsatellite in the camel Y chromosome, whereas microsatellite based on bovine sequences were not detected. The frequency of each allele varied among different populations. For the Nanjiang, Hexi and Alashan populations, a 243-bp allele was found. For the Sunite population, 241-bp, 243-bp and 247-bp alleles were detected, and the frequencies of these alleles were \(22.2\%\), \(44.5\%\) and \(33.3\%\), respectively; 241-bp and 243-bp alleles were found in other populations. Finally, CNVs in two Y-chromosomal genes were detected; CNV for HSFY and SRY ranged from 1 to 3 and from 1 to 9, respectively.     

Polymorphism of Alcohol Dehydrogenase Gene <Emphasis Type="Italic">ADH1B</Emphasis> in Eastern Slavic and Iranian-Speaking Populations

Frequencies of alleles and genotypes for alcohol dehydrogenase gene ADH1B (arg47his polymorphism), associated with alcohol tolerance/sensitivity, were determined. It was demonstrated that the frequency of allele ADH1B*47his, corresponding to atypical alcohol dehydrogenase variant in Russians, Ukrainians, Iranians, and mountain-dwellers of the Pamirs constituted 3, 7, 24, and 22%, respectively. The frequencies established were consistent with the allele frequency distribution pattern among the populations of Eurasia. Russians and Ukrainians were indistinguishable from other European populations relative to the frequency of allele ADH1B*47his, and consequently, relative to specific features of ethanol metabolic pathways. The data obtained provide refinement of the geographic pattern of ADH1B*47his frequency distribution in Eurasia.     

Genome-wide population genetic analysis identifies evolutionary forces establishing continuous population divergence

Elucidating the mechanism shaping the spatial variations of traits has long been a central concern of evolutionary biologists. Geographic clines of allele/morph frequencies along environmental gradients are suggested to be established and maintained by the balancing of two opposing evolutionary forces, namely selection that generates spatial differentiation in morph frequencies, and selection and/or stochastic factors that lead to the coexistence of multiple morphs within a population. Thus, testing for both selection and stochastic factors is necessary for a comprehensive understanding of the mechanism underlying clinal variation in morph/allele frequency in natural populations. Here, I identified the evolutionary forces responsible for clinal variation of color morph frequency in Ischnura senegalensis by comparing the population divergence of putatively neutral loci generated by high-throughput next-generation sequencing (F _STn) with that of the putative color locus (F _STc). No strong correlation was observed between F _STn and F _STc, suggesting that stochastic factors contribute less to color-locus population divergence. F _STc was less than F _STn between populations exposed to similar environmental conditions, but greater than F _STn between populations exposed to different environmental conditions, suggesting that both balancing selection and divergent selection act on the color locus. Therefore, two antagonistic selection factors rather than stochastic and historical factors contribute to establishing the clinal variation of morph frequency in I. senegalensis.     

De novo development and characterization of polymorphic microsatellite markers in a schilbid catfish, <Emphasis Type="Italic">Silonia silondia</Emphasis> (Hamilton, 1822) and their validation for population genetic studies

The stock characterization of wild populations of Silonia silondia is important for its scientific management. At present, the information on genetic parameters of S. silondia is very limited. The species-specific microsatellite markers were developed in current study. The validated markers were used to genotype individuals from four distant rivers. To develop de novo microsatellite loci, an enriched genomic library was constructed for S. silondia using affinity–capture approach. The markers were validated for utility in population genetics. A total number of 76 individuals from four natural riverine populations were used to generate data for population analysis. The screening of isolated repeat sequences yielded eleven novel polymorphic microsatellite loci. The microsatellite loci exhibited high level of polymorphism, with 6–24 alleles per locus and the PIC value ranged from 0.604 to 0.927. The observed (Ho) and expected (He) heterozygosities ranged from 0.081 to 0.84 and 0.66 to 0.938, respectively. The AMOVA analysis indicated significant genetic differentiation among riverine populations (overall F_ST = 0.075; P < 0.0001) with maximum variation (92.5 %) within populations. Cross-priming assessment revealed successful amplification (35–38 %) of heterologous loci in four related species viz. Clupisoma garua, C. taakree, Ailia coila and Eutropiichthys vacha. The results demonstrated that these de novo polymorphic microsatellite loci are promising for population genetic variation and diversity studies in S. silondia. Cross-priming results indicated that these primers can help to get polymorphic microsatellite loci in the related catfish species of family Schilbidae.     

Polymorphism of hordei-coding loci in Near Eastern local populations of cultivated barley (<Emphasis Type="Italic">Hordeum vulgare</Emphasis> L.)

Electrophoresis in starch gel has been used to study the polymorphism of hordeins encoded by loci Hrd A, Hrd B, and Hrd F in 140 local barley populations from the Near East, including 60, 34, 33, 8, and 5 populations from Syria, Jordan, Iraq, Palestine, and Israel, respectively. Fifty-seven Hrd A, 87 Hrd B, and 5 Hrd F alleles have been found. The alleles of these loci considerably differ in frequencies and distribution in populations from different Near Eastern countries. Cluster analysis of the matrix of the frequencies of alleles of hordei-coding locus alleles in barley populations from the Near East, North Africa, Ethiopia, and South Arabia has yielded two clusters. The first cluster includes barley populations from Israel, Palestine, Morocco, Tunisia, Algeria, and Egypt; the second cluster, populations from Iraq, Syria, Jordan, Yemen, and Ethiopia.