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Table of contents: 2019

Research Article

Brucella spp. are the pathogens responsible for brucellosis, which is a cosmopolitan and serious disease for animals and humans. Recent studies have revealed the presence of Brucella DNA in the reproductive tract tissues of buffaloes based on microbiological cultures collected from vaginal swabs. We tested for Brucella abortus DNA in the uterus, perivaginal lymph nodes, and uterine mucus of buffalo cows naturally infected with Brucella spp., as defined by a positive complement fixation test. Uterine tissue, uterine mucus, and perivaginal lymph node samples from 16 Brucella seropositive female buffaloes were analyzed. Brucella DNA was found in five of the uterine tissue samples, eight of the perivaginal lymph node samples, and 14 of the uterine mucus samples. Furthermore, Bayesian inference analysis indicated that the DNA sequences obtained from these tissues and mucus grouped with corresponding sequences of the B. abortus species.

Genet. Mol. Res. 18(3): GMR18376
DOI: 10.4238/gmr18376
Research Article

The Guzerat cattle breed, in past centuries, was utilized in Brazil mainly for work and transport in the coffee industry because of its rusticity; however, in recent decades it has become important for milk and meat production. Cattle traits such as rib-eye area, backfat thickness, and intramuscular fat percentage have been continuously evaluated in breeding programs because they are related to meat quality, carcass yield and organoleptic properties; however, the Guzerat breed has not been included in this type of study. In order to overcome these limitations, we estimated variance components, genetic correlations and heritability for ribeye area (REA), backfat thickness (BFT), rump fat thickness (RFT), intramuscular fat percentage (IMF), dry matter intake (DMI), average daily gain (ADG), scrotal circumference (SC), metabolic weight (MW), visual score for finishing (VSF), residual feed intake (RFI) and margin (MAR) from 1499 animals of the Guzerat breed. Genetic parameters and trait heritabilities were estimated using data collected from various breeders for each trait. The dataset was analyzed by the AIREMLF90 program. REA and MAR were the carcass and production traits with the greatest additive genetic variance; they also had the highest heritability values. The average inbreeding of animals in pedigree was 0.81%; more than 71% of animals had 0% inbreeding and only 0.04% of the animals had a coefficient over 25%. Carcass and production traits of Guzerat cattle analyzed in this study showed sufficient genetic variability to respond to a selection program, especially for the traits REA, RFT, IMF and ADG. Thus, selecting animals based on data obtained from this study will help improve Guzerat carcass quality, production efficiency and profit margins.

Genet. Mol. Res. 18(3): GMR18413
DOI: 10.4238/gmr18413
Research Article

Genotoxicity caused by heavy metals can negatively affect vital processes of crop plants, though remedial measures can be used to reduce such damage. We examined the possible stimulatory and phytotoxicity impacts of three nanosized titanium dioxide (nTiO2) doses on soybean (Glycine max) and how adsorption of lead (Pb) onto the surface of nTiO2 may attenuate the toxic action of Pb on soybean by comparing the toxicity of three Pb doses before and after the adsorption process. The exposure time was 48 h. Phenotypic parameters (seedling growth, phytotoxicity, tolerance and vigor indices), cytogenetic tests of pollen grain performance, and DNA status (using flow cytometry, comet assays and analysis of RAPDs) were used as bioassays to assess the effect of the treatments. The optimal nTiO2 dose was 10 mg.L-1 because it i) stimulated and accelerated seedling development parameters, fertility and germination of pollen grains, ii) increased nuclear DNA content and decreased the extent of DNA damage, and iii) generated the maximum number of amplified DNA bands as an indicator for appearances of new DNA bands (genes) more than the control. Doses of nTiO2 higher and lower than the optimal dose resulted in a gradual decline in these parameters, especially the higher dose. The three doses of Pb induced notable inhibitory and genotoxic impacts on all biomarkers used, in a dose-dependent manner. We conclude that the powdered state of optimal dose (10 mg) had a good ability to adsorb Pb onto its surface and consequently mitigated its toxicity. This was evident through the significant amelioration of parameters of each biomarker after application of the three Pb adsorbate solutions on soybean seeds. Therefore, we suggest that stimulatory and adsorbent nTiO2 dose may be used in the future to protect against heavy metal toxicity in economically important plants.

Genet. Mol. Res. 18(3): GMR18350
DOI: 10.4238/gmr18350
Research Article

Local cassava varieties play an important role in food security and the autonomy of subsistence farmers. They can be important resources for breeding and conservation programs. We examined the genetic diversity of cassava through ethnobotanical knowledge and microsatellite markers to understand the dynamics of conservation and management of the varieties used local small-scale farmers of a rural quilombo (a slave-descendant community) in Mato Grosso, Brazil. To obtain ethnobotanical information, semi-structured interviews were applied to 10 family units who cultivated cassava. Each family cultivated from one to five varieties, with 2.3 ± 1.16 varieties/farmer, on average. Genetic analysis was was made of the 11 local varieties with microsatellite markers (12 loci). Despite low ethnobotanical diversity (H' = 2.05), high genetic diversity was found (Na = 6.75, HO = 0.92, H­E = 0.75, on average) in these local varieties. These farmers, who derive their income mainly from cassava cultivation and flour production for the market, direct their variety choices to those that are most productive. Brava variety was the most frequent (found in eight family units) and was considered the most profitable for the production of flour Network analysis showed that propagule circulation and information occurs between the residents and also with other communities of the region, which are important sources of new varieties. Two farmers were identified as the most active in this network, showing potential as key elements for the circulation of propagating material. According to the cluster analysis using the genetic data, the most recently introduced varieties (Baixinha, Liberatona, Broto roxo, Mansa, Ramo branco, Carneiro and Cuiabana) are separated from those introduced a long time ago. The varieties pointed out as bitter by the farmers were also grouped together. The results showed the importance of traditional farmers in maintaining a high genetic diversity of manioc varieties, despite the directing of the choice of varieties to meet market needs.

 

Genet. Mol. Res. 18(3): GMR18326
DOI: 10.4238/gmr18326
Research Article

The HIV/AIDS associated lipodystrophy syndrome is characterized by alterations in body fat and metabolism. We investigated whether CCR5Δ32 polymorphisms are associated with development of lipodystrophy. We made a case-control study of 248 HIV/AIDS patients who used antiretroviral therapy; they were divided into a group of patients (n = 148) who had lipodystrophy and a control group (n = 100) that did not present this syndrome. Both groups answered a questionnaire concerning age, gender and level of physical activity. DNA was extracted from blood samples using the mini salting out technique and PCR to identify polymorphisms of the CCR5Δ32 gene. Among lipodystrophy patients, most were men (64.8%) and 56.2% were sedentary. We found no significant association of the CCR5Δ32 allele with prevalence of lipodystrophy. However, male homozygotes were more susceptible to lipodystrophy (OR 1.78, P = 0.0350). We observed that the highest incidence of lipodystrophy was in sedentary men. More studies would be needed, using other markers, to allow precise use of genetic polymorphisms as a diagnostic parameter for lipodystrophy syndrome.

Genet. Mol. Res. 18(3): GMR18227
DOI: 10.4238/gmr18227
Research Article

Type 1 Diabetes mellitus (T1D) is caused by the immune-mediated destruction of insulin-producing islet β cells, and its pathogenesis involves cytokines. Genetic background may influence cytokine signals, and polymorphisms may determine their impact on T1D autoimmunity. Several polymorphisms in and close to Interleukin-6 (IL-6) and Interleukin-6 Receptor (IL-6R) have been identified as associated with pathological processes. We investigated the IL-6 promoter -174G>C (rs1800795) and IL-6R Asp358Ala (rs2228145) polymorphisms in 141 Euro-Brazilian patients with adult-onset type 1 diabetes (diagnosis > 18 years old) and 150 healthy controls, matched by gender and age. Genotyping for both polymorphisms was performed by PCR-RFLP. PCR fragments for rs1800795 with Hsp92II and rs1800795 with HindIII were resolved by 15% polyacrylamide gel electrophoresis. The polymorphisms in both groups were in Hardy-Weinberg equilibrium. IL-6 rs1800795 was not different between healthy controls and T1D subjects, showing 27.3% (95% CI, 20 - 35%) and 30.1% (23 - 38%) for the C minor allele (-174C), respectively. For IL-6R rs2228145, the genotype (P = 0.046) and allele (P = 0.021) were different in the groups. The frequencies for rs2228145 C minor allele (358Ala) were 34.7% (27 - 43%) and 44.0% (36 - 51%) for controls and T1D subjects, respectively. In conclusion, IL-6 rs1800795 was not associated with adult-onset T1D; however, IL-6R rs2228145 was associated with T1D development in adulthood, and carriers of the minor C allele are at increased risk for adult-onset T1D (OR = 1.48; 95% CI = 1.06 - 2.07).

Genet. Mol. Res. 18(3): GMR18260
DOI: 10.4238/gmr18260
Research Article

Brazil is the third world largest maize producing country, and Paraná state is the second largest producer state of this essential crop in this country. The bacterial microbiota of cereal grains depends on the environment where they were grown, handled, and processed – and it can influence plant growth and food safety. The industrial enzymes market is rapidly increasing around the globe, and new producer microorganisms are in demand. Hydrolases correspond to 75% of all industrial enzymes. Considering the dearth of information about maize bacterial microbiota in Brazil and that this microbiota might produce hydrolases for degrading maize grains biomolecules, we examined the bacteria of maize grains within a region of Paraná state and looked for hydrolytic enzymes producers. Harvest leftover dried maize ears presenting rotting symptoms were collected from three different farms in two towns of the North Central region of Paraná state. The ears were threshed, and a grain portion of each ear was incubated in peptone water. Aliquots of this suspension were diluted and inoculated in nutrient agar. Individualized and morphologically diverse colonies were transferred to selective media containing starch, microcrystalline cellulose, skimmed milk, or triolein. Halo development around the bacterial colonies was representative of hydrolase production. Isolates (n = 137) presenting hydrolytic activity were stored, and their biochemical profile was analyzed. Fifty-five isolates that had unique biochemical characteristics were chosen to be molecularly identified by DNA barcoding. A phylogenetic tree showed that most of the bacterial strains belonged to the phylum Proteobacteria, but some also were from the phyla Actinobacteria and Firmicutes. Some of the isolated species had already well-characterized enzymes. However, new producers were also found, including amylase producing isolate of Massilia timonae and a lipase producing isolate of Pantoea dispersa.

Genet. Mol. Res. 18(3): GMR18320
DOI: 10.4238/gmr18320
Research Article

We appled a genetic and phenotypic multi-character predicted approach to the use of the multivariate methods Additive Main effects and Multiplicative Interaction (AMMI) and Genotype Main Effects and Genotype Environment Interaction (GGE). The experiment was carried out in the agricultural crop year of 2016 in the state of Rio Grande do Sul, Brazil. The experimental design was a randomized block design, with 14 growing environments x five wheat genotypes arranged in three replications. The characters were falling number, gluten strengthand protein content, which were used to make multi-character the technological index of the industrial quality of the wheat grains and multi-character the technological index of the industrial quality of the wheat grains. Multi-character selection can be a useful tool for identifying genotypes and growing environments that maximize the industrial quality of wheat grain. The GGE method provides greater explicability of the effects of genotype x environment interaction based on multi-character selection. The multicharacter genetic approach predicted for the selection of the industrial quality of wheat grain results in reliable inferences in the indication of adaptability and stability for the AMMI method and for GGE.

Genet. Mol. Res. 18(3): GMR18223
DOI: 10.4238/gmr18223
Research Article

We evaluated how genetic x environment (G x E) interactions affect grain productivity in corn hybrids grown in traditional and non-traditional environments in the off or “second” season. Adaptability and stability of the hybrids was examined by parametric, nonparametric and multivariate methods. In 2016, 24 hybrids were evaluated in seven environments, in 2017, 13 hybrids were evaluated in six environments. The environments were located between the regions of Southwestern and Southeast Goiás state; Triângulo Mineiro and Alto Paranaíba, in the western and northwestern regions of Minas Gerais state. In all trials, complete randomized blocks were adopted, and grain productivity was determined. The statistical analyses were performed with two different softwares: Estabilidade and Genes. It was observed that in both seasons, the locals considered as traditional corn cultivation in the off season Jataí-GO and Montividiu-GO gave the highest yields, with average yields higher than national averages, producing 3859 kg.ha-1 in 2016 and 5562 kg.ha-1 in 2017. The methods of Eberhart and Russell, Lin and Binns modified by Carneiro, Centroid and AMMI gave similar results in the rankings of the adaptation and stability of the hybrids. We concluded that the G x E interaction for grain productivity of corn hybrids grown in the off-season is complex in nature.

 

Genet. Mol. Res. 18(3): GMR18193
DOI: 10.4238/gmr18193
Research Article

Estimating the performance of a rice breeding program is possible by means of indexes such as the replacement rate, which quantifies the dynamism of the breeding program and provides the rate of included, excluded, maintained and renewed genotypes year after year. We evaluated the performance of the irrigated rice breeding program in the state of Minas Gerais, conducted by the EPAMIG/UFV/EMBRAPA consortium. A total of 210 lines were evaluated in the municipalities of Janaúba, Leopoldina and Lambari from 1993 to 2016. The average number of genotypes included, maintained and excluded in each year were calculated, along with the replacement rate percentage. The average genotype replacement rate was 44% for Lambari and Janaúba, and 43% for Leopoldina. The average maintenance in Lambari was 39%, and in Janaúba and Leopoldina it was 40%. In all localities, the mean rate of inclusion of genotypes was higher than the average exclusion rate, indicating good efficiency in the irrigated rice breeding program. However, new strategies should be used in the irrigated rice breeding program to increase the genetic basis of lines and increase the replacement rate.

 

Genet. Mol. Res. 18(3): GMR18332
DOI: 10.4238/gmr18332
Research Article

Atherosclerosis is a chronic multifactorial inflammatory disease that evolves in response to aggression of the endothelium, causing plaque formation in large or medium-sized arteries. Various co-factors can accelerate the evolution of this pathology, such as systemic arterial hypertension, dyslipidemia and diabetes mellitus. Given that nitrous oxide is a potent vasodilator and that its synthesis depends on the activity of the endothelial nitric oxide synthase (eNOS), we examined a possible association of the eNOS-T786C polymorphism (which reduces nitrous oxide synthesis) in atherosclerotic patients who have symptoms of hypertension, dyslipidemia or diabetes. We made a case-control study of two groups of 100 atherosclerotic patients, one with at least one of the above symptoms and the other a control group with atherosclerosis, but with none of the above symptoms. The samples were submitted to DNA extraction, then to PCR and analyzed on agarose gels. We found no significant association of the T786C (eNOS) polymorphism with the cofactors hypertension, dyslipidemia or diabetes. In addition, no association was found between smoking and eNOS T786C polymorphism. As for drinking, there was also no association with this polymorphism and or with cofactors.

Genet. Mol. Res. 18(3): GMR18269
DOI: 10.4238/gmr18269
Research Article

During maturation in seeds, metabolic processes dependent on gene expression are controlled by hormones, including abscisic acid and gibberellin. These hormones determine dormancy or the capacity for germination in seeds and may have different expression levels in the endosperm and embryo of coffee seeds. We quantified gene expression in the biosynthetic pathway of gibberellin and abscisic acid in different parts of Coffea arabica L. seeds in pre and post physiological maturity, in order to better understand the germination mechanisms of this species. Coffee fruits were harvested at green, yellowish-green, cherry, over-ripe and dry stages. For studies of gene expression, intact seeds were used in addition to endosperm and isolated embryos. The RNA from different tissues was extracted and treated with DNAse to synthesize cDNA. Transition levels of CaGA3 (gibberellin) and CaABI3 (abscisic acid) genes were quantified with qRT-PCR, using specific primers for coffee. Intact seeds at each phenological stage were submitted to germination tests, to evaluate the physiological quality of the seeds.  Seed harvested at green and dry stages showed lower physiological quality when compared to the other maturation stages, and germination at the green stage was close to zero. Greatest expression of CaGA3 and CaABI3 occurs in the endosperm of coffee seeds in cherry and over-ripe stages, with better physiological performance. There are differences in CaABI3 and CaGA3 gene expression in embryos and endosperm of the coffee seeds.

 

Genet. Mol. Res. 18(3): GMR18264
DOI: 10.4238/gmr18264
Research Article

The species Syagrus romanzoffiana, a native palm tree of South America, is widely distributed and well adapted to southern Brazil. It is an important economic, cultural, and ecological resource, being the preferred food of diverse animal species, involving complex ecological relationships. However, despite numerous molecular studies on native plants, specific molecular markers, such as expressed sequence tag-simple sequence repeats (EST-SSRs), are lacking, and there are few SSR markers for this species. Molecular data about individuals and their populations offers new perspectives for management, conservation, and economic exploitation. Here we tested 21 microsatellite loci known from three species of the family Arecaceae in three native populations of S. romanzoffiana in the state of Rio Grande do Sul, in southern Brazil. Among the 21 primer pairs tested, 12 produced an amplification product. Five loci were chosen and subjected to diversity tests. The populations presented between three and nine alleles per locus, and acceptable genetic diversity values; the expected heterozygosity ranged from 0.460 to 0.864, while the observed heterozygosity ranged from 0.100 to 1.000. We conclude that various microsatellite markers developed for other species of the family Arecaceae are suitable for molecular analysis of S. romanzoffiana populations.

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Genet. Mol. Res. 18(3): GMR18183
DOI: 10.4238/gmr18183
Research Article

The production of peach rootstocks in Brazil is still performed mainly from seeds of different cultivars, whose endocarps are obtained in peach canning industries. This type of material is not ideal for use as rootstocks, since it is a varietal blend of genotypes with differing in physical and physiological characteristics which can include germination and growth of seedlings. We examined the genetic divergence of peach rootstock based on the relative contribution of 15 seed and endocarp characteristics, using multivariate procedures, in order to help select promising crosses for genetic improvement. Endocarp and seeds from eight rootstock cultivars of Prunus persica suggested as appropriate for cultivation in southern Brazil were evaluated for the biometric characteristics of length, width, thickness and fresh weight, and the seeds were submitted to a germination test. An analysis of variance of the data, principal component analysis and clustering using Tocher's optimization method were carried out. Genetic variability was found among the cultivars for all the characteristics. The characteristics with the greatest contribution to the genetic divergence between rootstocks were endocarp fresh weight, seed width and thickness, and germination percentage. On the basis of principal component analysis, using the variables with the greatest power of discrimination, the cultivars were divided into four groups. For breeding programs we suggest crosses between the cultivars Flordaguard χ Capdeboscq, Capdeboscq χ Tsukuba 1 and Capdeboscq χ Okinawa, aimed at obtaining improved peach rootstock with superior seed and seedling vigour, together with other characteristics of interest for farmers in southern Brazil.

 

Genet. Mol. Res. 18(3): GMR18345
DOI: 10.4238/gmr18345
Research Article

MC4R, FABP3 and DGAT1 are important genes related to productive and reproductive traits in pigs, such as food intake, growth rate, back fat thickness reduction and lactation. Selection of pigs for lean meat production may lead to losses in reproductive charcters because reduction of backfat thickness and low feed intake during the lactation phase can affect reproduction. To examine this possibility, we evaluated possible associations of SNPs in the MC4R (SNPg.1,578C>T), FABP3 (SNPg.240T>C) and DGAT1 (SNPg.9,422C>T) genes with the number of weaned piglets, birth weight, total weight of litter at birth, total litter weight at weaning, age at first mating and parity interval in 227 animals of two maternal lines: European and European/Chinese pigs. Specific fragments of the genes under study were amplified by Multiplex ARMS-PCR and genotyped in an automatic sequencer. SNPs in the MC4R (SNPg.1,578C>T) and FABP3 (SNPg-240T>C) genes showed three genotypic variations in both lines, while the SNP (SNPg.9,422C>T) of the DGAT1 gene had three genotypic variations in European swine and two genotypic variations (homozygotes) in the European/Chinese breed. Polymorphisms of MC4R, FABP3 and DGAT1 genes evaluated by variance analysis had significant associations with the reproductive traits age at first mating and parity interval, while only the DGAT1 gene in the European line was significantly associated with the production traits mean weight at weaning and total litter weight at birth andnd weaning.

Genet. Mol. Res. 18(3): GMR18139
DOI: 10.4238/gmr18139

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