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The present study aimed to estimate the genetic parameters for direct and maternal influences on birth weight (BW), weaning weight (WW) and postweaning weight (PW) of Texel sheep, raised in an extensive system from Brazil. Data file used in this study consisted of 834 body weight records of 834 Texel lambs (376 males and 458 females) born from 2020 to 2021, offspring of 475 ewes and 45 rams. Multivariate animal model was conducted to estimate the variance components, heritability and genetic correlations using the restricted maximum likelihood method in ASReml-R software, while the effects of fixed factors were analyzed by the general linear model procedure of statistical analysis system. Five different animal models, with or without maternal genetic effect, maternal permanent environment effect and covariance between additive genetic and maternal genetic effects, were fitted on the growth traits data of the Texel sheep population. AIC and BIC test results were used to evaluate the best fit models for growth traits. The effect of lamb’s sex was significant on BW, WW and PW while birth type and year of lambing effects were on all traits (P < 0.05). Model 4, incorporating direct additive genetic, maternal additive genetic and maternal permanent environmental effects showed the minimum AIC estimate for all growth traits. The direct additive genetic heritability for BW, WW and PW were 0.11 ± 0.03, 0.37 ± 0.05 and 0.31 ± 0.08, respectively and maternal heritability for these traits were 0.00 ± 0.00, 0.04 ± 0.02 and 0.00 ± 0.00, respectively. The total heritability estimates for BW, WW and PW were 0.11 ± 0.03, 0.39 ± 0.05 and 0.31 ± 0.08, respectively. The estimates of the direct additive genetic correlation between BW-WW, BW-PW and WWPW were 0.68 ± 0.12, 0.66 ± 0.12 and 0.78 ± 0.07, respectively. The maternal permanent environmental correlation between BW-WW, BW-PW and WW-PW were 0.38 ± 0.27, 0.29 ± 0.20 and 0.74 ± 0.16, respectively. Phenotypic correlation ranged from 0.43 ± 0.03 to 0.75 ± 0.02. It is concluded that due to the existence of genetic variation for BB, WW and PW and strong genetic correlation among them, genetic progress for these traits is possible by selection in Texel sheep from Brazil. [ABSTRACT FROM AUTHOR]

Plague is a deadly zoonosis that still poses a threat in many regions of the world. We combined epidemiologic, host, and vector surveillance data collected during 1961– 1980 from the Araripe Plateau focus in northeastern Brazil with ecologic, geoclimatic, and Yersinia pestis genomic information to elucidate how these factors interplay in plague activity. We identified well-delimited plague hotspots showing elevated plague risk in low-altitude areas near the foothills of the plateau’s concave sectors. Those locations exhibited distinct precipitation and vegetation coverage patterns compared with the surrounding areas. We noted a seasonal effect on plague activity, and human cases linearly correlated with precipitation and rodent and flea Y. pestis positivity rates. Genomic characterization of Y. pestis strains revealed a foundational strain capable of evolving into distinct genetic variants, each linked to temporally and spatially constrained plague outbreaks. These data could identify risk areas and improve surveillance in other plague foci within the Caatinga biome. [ABSTRACT FROM AUTHOR]

Adaptive genetic and neutral variations are essential for maintaining population viability in changing environmental conditions. Habitat loss and fragmentation can be reflected in the patterns of genetic variation in the populations. White-lipped peccaries (WLPs, Tayassu pecari) are wide-ranging Neotropical ungulates with important ecological roles in the ecosystem suffering local extinctions worldwide. Here, we used a RAD-seq protocol to genotype 192 individuals. After filtering, we identified sets of SNP markers (ranging from 147 to 151,792 SNPs) to assess the genetic diversity and population structure of WLPs from Pantanal, Cerrado, and Atlantic Forest in Brazil. We found signals of loss (θw < θπ) and lower genetic diversity (allelic richness, nucleotide diversity, and observed and expected heterozygosities) in the Central Cerrado and Atlantic Forest populations. Principal Component Analysis (PCA) and admixture analyses (NGSAdmix) using genome-wide and neutral SNP data sets showed three major genetic clusters according to the biomes. Multiple matrix regression with randomization (MMRR) analysis found an isolation-by-distance pattern explaining the neutral genetic differentiation. We used Latent Factor Mixed Models (LFMM) and Redundancy Analysis (RDA) to identify candidate SNPs involved in different biological processes, such as metabolism and immune and neuronal responses, mainly associated with temperature and precipitation variables. We found an adaptive population genetic structure, suggesting three adaptive units with significant patterns of isolation-by-distance and isolation-by-environment. Our results highlighted the importance of conservation strategies for maintaining the genetic diversity of WLP populations. Furthermore, conservation plans and translocation programs should preserve and consider the adaptive variation. [ABSTRACT FROM AUTHOR]

The hoary fox (Lycalopex vetulus) is the only species of the Canidae (Mammalia: Carnivora) endemic to Brazil, and so far has been the target of few genetic studies. Using microsatellites and mtDNA markers, we investigated its present genetic diversity and population structure. We also tested the hypothesis that this species currently hybridizes with the pampas fox (L. gymnocercus), as suggested by previous mtDNA data from two individuals. We collected tissue and blood samples from animals representing most of the two species' distributions in Brazil (n  = 87), including their recently discovered geographic contact zone in São Paulo state. We observed that the hoary fox exhibits high levels of genetic diversity and low levels of population structure. We identified six individuals from São Paulo state with clear evidence of hybridization based on introgressed pampas fox mitochondrial DNA and/or admixed microsatellite genotypes (three individuals bore both types of evidence). These results demonstrate the existence of admixed individuals between hoary and pampas foxes in southeastern Brazil, representing the first identified case of interspecies admixture between native South American canids. We discuss our findings in the context of the evolutionary history of these foxes and address potential conservation implications of this interspecies hybridization process. [ABSTRACT FROM AUTHOR]

Once fishes and rivers are intrinsically connected, historical events such as river captures and the reconfiguration of palaeodrainages affect population structure and species distribution. However, direct evidence of these events remains limited.We aimed to directly infer putative connections between adjacent river basins to understand genetic and geographical patterns in populations and species of the 'Geophagus' brasiliensis complex. For that, we analysed 174 sequences of the mitochondrial gene cytochrome c oxidase subunit I (COI) from five species along 35 sites within and near a coastal basin in northeastern Brazil. Based on haplotype network, palaeodrainage reconstruction, geological inferences of river captures and analyses of molecular variance (AMOVAs), we tested how the genetic structure could be associated with variable patterns of habitat connectivity through time.In general, high levels of genetic variation were identified, including shared haplotypes among drainages for most species. AMOVA suggested that drainage rearrangements between adjacent basins were the main drivers of genetic diversification in the 'G.' brasiliensis complex.Our study refuted dispersal routes via the continental shelf, whereas eight putative river captures suggested historical connections that enabled gene flow among drainages until recent interruption. These results provide novel insights on the role of riverscape evolution on the biogeography of neotropical ichthyofauna. [ABSTRACT FROM AUTHOR]

Introduction and aim: Type 3 Familial Partial Lipodystrophy (FPLD3) is a rare metabolic disease related to pathogenic PPARG gene variants. FPLD3 is characterized by a loss of fatty tissue in the upper and lower limbs, hips, and face. FPLD3 pathophysiology is usually associated with metabolic comorbidities such as type 2 diabetes, insulin resistance, hypertriglyceridemia, and liver dysfunction. Here, we clinically and molecularly characterized FPLD3 patients harboring novel PPARG pathogenic variants. Materials and methods: Lipodystrophy-suspected patients were recruited by clinicians from an Endocrinology Reference Center. Clinical evaluation was performed, biological samples were collected for biochemical analysis, and DNA sequencing was performed to define the pathogenic variants associated with the lipodystrophic phenotype found in our clinically diagnosed FPLD subjects. Bioinformatics predictions were conducted to characterize the novel mutated PPARγ proteins. Results: We clinically described FPLD patients harboring two novel heterozygous PPARG variants in Brazil. Case 1 had the c.533T > C variant, which promotes the substitution of leucine to proline in position 178 (p.Leu178Pro), and cases 2 and 3 had the c.641 C > T variant, which results in the substitution of proline to leucine in the position 214 (p.Pro214Leu) at the PPARγ2 protein. These variants result in substantial conformational changes in the PPARγ2 protein. Conclusion: Two novel PPARG pathogenic variants related to FPLD3 were identified in a Brazilian FPLD cohort. These data will provide new epidemiologic data concerning FPLD3 and help understand the genotype-phenotype relationships related to the PPARG gene. [ABSTRACT FROM AUTHOR]

Seventy-five pectinolytic strains collected from vegetables grown in the counties of Santarém, Belterra, and Mojuí dos Campos, located in the western region of the Pará State, Brazil, were studied according to their pathological and genetic variability. The strains were grouped in 5 clusters according to pathogenicity in potato, pepper, carrot, and onion, and 38 strains were selected for genetic analysis using rep-PCR. These strains were divided into 35 genetic groups according to rep-PCR at 70% similarity. These results indicated high pathological and genetic variability of the strains causing soft rot in vegetables in the western region of the Pará State, which will be used in etiological research and for the development and assessment of management techniques for the soft rot in vegetables in this region. [ABSTRACT FROM AUTHOR]

Cleistogamy is characterized by the presence of flowers that are permanently closed, yet they still produce fruits and seeds through autonomous self‐pollination. Populations with cleistogamous flowers can also have flowers that open, called chasmogamous, which promote cross‐pollination and genetic variability. Acanthaceae is among the families with the highest frequency of cleistogamy, observed mainly in Ruellia. This study aimed to assess cleistogamy in Ruellia blechum for the first time. In a population in Central Brazil, we analysed the production of cleistogamous and chasmogamous flowers, their fruiting, differences in flower bud size, self‐pollination in cleistogamous flowers and visitors in chasmogamous flowers. Of the flower buds observed, 35.29% remained closed (cleistogamous flowers), with 31.25% of them forming fruit. In contrast, 60.24% of the flowers that opened (chasmogamous) developed fruit. The length of cleistogamous flowers was shorter than that of chasmogamous floral buds in pre‐anthesis. On average, 24.45 pollen grains were self‐deposited on the stigma of a cleistogamous flower. The chasmogamous flowers were visited mainly by small bees. This study is the first to confirm the presence of cleistogamous flowers in R. blechum. However, their co‐occurrence with chasmogamous flowers suggests a fitness advantage for maintaining a mixed mating strategy. [ABSTRACT FROM AUTHOR]

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The expansion of forest plantations to supply the wood market requires selection of genotypes that can provide high gains, which may compromise long-term tree breeding programs. With the final purpose of producing quality sawn wood, the aims of this study were to: (a) estimate genetic parameters for a progeny/provenance test of Plathymenia foliolosa Benth; (b) carry out optimized selection based on an inbreeding rate (F) from 0 to 7% in progeny/provenance tests evaluated at 35 months for P. foliolosa and Cordia trichotoma (Vell.) Arrab. ex Steud, and at 42 months for Zeyheria tuberculosa (Vell.) Bureau ex Verl.; (c) develop a practical index for balancing gains and F; d) and indicate the most appropriate genetic base structure based on effective population size ( N e ) to subsidize conservation strategies, breeding programs, and clonal orchard with those species native from Brazil. Diameters at breast height (DBH) were obtained in progeny/provenance tests conducted in the south of Bahia–Brazil. For P. foliolosa, the moderated heritability (h2a) value of 0.55 demonstrated favorable conditions for selection based on DBH. For this trait, there is better possibility of achieving progressive gains by exploiting genetic variability into the families (CVgi). Simulation of scenarios without optimization for P. foliolosa, C. trichotoma and Z. tuberculosa showed a high possibility of gains for breeding programs, ranging between 95.6 and 311.05%. However, in those scenarios, high rates of F were also observed. For the three species, selection based on the selection optimization index (SOI) was proposed in order to balance ideal increments in genetic gains and maintenance of genetic diversity. With the use of SOI, it was possible to simulate selection of scenarios with good prospects of gain balanced with N e in a practical and direct manner for germplasm conservation strategies, production of improved seeds in clonal orchards, and tracking recombination cycles within breeding populations. [ABSTRACT FROM AUTHOR]

Roupala montana var. brasiliensis is a timber tree species native to the Cerrado and Atlantic Forest areas of Brazil. The wood was exploited for international markets, but there is no information on the conservation status of its natural populations, nor on other key aspects, such as mating system, gene flow, and inbreeding depression, essential for the species' sustainable management and conservation. We report the first study of any Roupala species to apply a validated set of species-specific microsatellite markers to genotype adults, juveniles, and seedlings, and analyse genetic diversity, inbreeding, effective population size, and mating system. We studied four populations of the species in areas of mixed Ombrophilous forest with different disturbance levels (undisturbed to strongly disturbed) in southern Brazil. The species occurs at low frequency in the study forests, but the populations are genetically diverse without significant differences in genetic diversity levels related to disturbance. The study also indicated resistance to the severe fragmentation associated with low density of individuals, with a stable mating system showing preferential outcrossing, with some inbreeding (tm ≈ 0.83, F > 0.165). Despite being spatially isolated from each other, the populations are not reproductively isolated, receiving immigrant pollen from long distances, although there was no evidence of gene flow into the populations via seeds. Seedlings from self-fertilization show low levels of inbreeding depression, which may reflect earlier pre-germination selection events. There was loss of allelic wealth in the younger cohorts, which may be a warning of the fragility of the genetic diversity detected in populations. We consider the implications of the results for the development of ex and in situ conservation and tree improvement programs. [ABSTRACT FROM AUTHOR]

Native to the tropical Americas, guava (Psidium guajava L.) is an important crop in Brazil. However, the emergence of so-called guava decline, a complex disease resulting from root parasitism by the root-knot nematode (Meloidogyne enterolobii Yang & Eisenback) in association with opportunistic fungi, has decimated guava orchards across Brazil and in other countries. In the present study, seminiferous guava accessions were vegetatively propagated by minigrafting and their genotypes preserved for resistance reassessment in clones to confirm or not host plant reactions. The results indicated a highly virulent parasite, high host suitability of the P. guajava species, and widely varying reactions among plants of the same genotype and between different genotypes, demonstrating that the strategy of preserving the germplasm and reassessing reactions in clones may be important in identifying and selecting germplasms with a degree of resistance to M. enterolobii. The progeny of cv. Paluma P02R5R2 obtained the lowest average parasite reproduction factor (RF = 22.11) among the genotypes evaluated and was; therefore; classified as moderately resistant and preserved for future research. [ABSTRACT FROM AUTHOR]

Cartilage-hair hypoplasia syndrome (CHH) is an autosomal recessive disorder frequently linked to n.72A>G (previously known as n.70A>G and n.71A>G), the most common RMRP variant worldwide. More than 130 pathogenic variants in this gene have already been described associated with CHH, and founder alterations were reported in the Finnish and Japanese populations. Our previous study in Brazilian CHH patients showed a high prevalence of n.197C>T variant (former n.195C>T and n.196C>T) when compared to other populations. The aim of this study was to investigate a possible founder effect of the n.197C>T variant in the RMRP gene in a series of CHH Brazilian patients. We have selected four TAG SNPs within chromosome 9 and genotyped the probands and their parents (23 patients previously described and nine novel). A common haplotype to the n.197C>T variant carriers was identified. Patients were also characterized for 46 autosomal Ancestry Informative Markers (AIMs). European ancestry was the most prevalent (58%), followed by African (24%) and Native American (18%). Our results strengthen the hypothesis of a founder effect for the n.197C>T variant in Brazil and indicate that this variant in the RMRP gene originated from a single event on chromosome 9 with a possible European origin. [ABSTRACT FROM AUTHOR]

Aim: The response of South American seasonally dry tropical forest (SDTF) and savanna species to the Quaternary climate changes is still poorly understood. Here we use multi‐model inference approach to compare the phylogeography and demographic history of five trumpet tree species (also known as pau‐d'arco) and draw general biogeographical patterns: Handroanthus impetiginosus, H. ochraceus, H. serratifolius, Tabebuia aurea and T. roseoalba. Location: Amazonia, Atlantic Forest, Cerrado and Caatinga ecoregions, South America and Brazil. Taxa: Bignoniaceae, Tabebuia Alliance, trees. Methods: We compiled genetic data, occurrence records and ecological niche modelling (ENM) from published articles. We used coalescent modelling to test patterns of co‐divergence, and analysed niche breadth and overlap and spatial patterns in genetic diversity using quantile regressions. Results: Species showed concordant lineage divergence times in the Pleistocene. Lineage diversification and phylogeographical patterns are more related to species niche breadth than to biome (savanna or SDTF). Differences in genetic diversity among species matches the expected for the demographic scenarios obtained with coalescent simulations and ENMs: species with wider range expansion during the Last Glacial Maximum had higher diversity than species with range retraction or multiple refugia. Main Conclusions: Diversification burst in the Pliocene, and major diversification of lineages during the Pleistocene seems to be a general pattern in SDTF and savannas in the South America. The high number of haplotypes at the Central Brazil, corresponding to the Cerrado ecoregion, highlights the importance of Protected Areas for SDTFs and savannas, highly threatened biomes in Brazil. [ABSTRACT FROM AUTHOR]

• Forage cactus in semiarid region: morphological and nutritional characterization. • Forage cactus: sustainable food alternative and coexistence with drought. • Variability in forage cactus: morphology and nutrition. • Morphological and nutritional variability in cladodes. • Genetic diversity of forage cactus for technology development. The plant species of the genus Opuntia are widely cultivated in the Semiarid region of Brazil and are considered as a sustainable technological alternative for coexistence with drought. The objective of this work was to characterize, by order of the cladodes, seven varieties of forage cactus of the genus Opuntia , cultivated under a rainfed regime, through morphological and nutritional parameters. The study was conducted at the IPA Experimental Station in the city of Caruaru-PE. The experimental design used was in randomized blocks, with three replicates. The varieties studied were: Gigante, Redonda, Clone IPA-20, F-08, Orelha de Elefante Mexicana, V-19 and Orelha de Elefante Africana. The number of total cladodes of the plant (NC), cladode length (CL), cladode width (CW), cladode area (CA), cladode thickness (CT), cladode volume (CV), cladode perimeter (CP), total fresh weight (FW), total dry weight (DW), total photosynthetic area (TPA), cladode area index (CAI), plant height (PH), plant width (PW), total fresh matter yield (TFMY), total dry matter yield (TDMY), total water accumulation (H 2 O), survival (SV), dry matter (DM), mineral matter (MM), organic matter (OM), neutral detergent fiber (NDF), acid detergent fiber (ADF), protein (P), hemicellulose (HEM), nitrogen (N), potassium (K) sodium (Na) and calcium (Ca) were determined at two years of age of the plants. Variability was observed in some of the morphological and/or nutritional characteristics among the order and/or phenological stage of the cladodes within the varieties. The varieties were divergent among themselves in the characteristics, NC, CL, CW, CA, CT, CV, CP, PH, PW, SV, P, N and Ca; and are related to genetic variation among the materials. The knowledge of the variability existing within and among botanical materials of forage cactus serves for the development of technologies aimed at each genetic material. [ABSTRACT FROM AUTHOR]

The MHC class I region contains crucial genes for the innate and adaptive immune response, playing a key role in susceptibility to many autoimmune and infectious diseases. Genome‐wide association studies have identified numerous disease‐associated SNPs within this region. However, these associations do not fully capture the immune‐biological relevance of specific HLA alleles. HLA imputation techniques may leverage available SNP arrays by predicting allele genotypes based on the linkage disequilibrium between SNPs and specific HLA alleles. Successful imputation requires diverse and large reference panels, especially for admixed populations. This study employed a bioinformatics approach to call SNPs and HLA alleles in multi‐ethnic samples from the 1000 genomes (1KG) dataset and admixed individuals from Brazil (SABE), utilising 30X whole‐genome sequencing data. Using HIBAG, we created three reference panels: 1KG (n = 2504), SABE (n = 1171), and the full model (n = 3675) encompassing all samples. In extensive cross‐validation of these reference panels, the multi‐ethnic 1KG reference exhibited overall superior performance than the reference with only Brazilian samples. However, the best results were achieved with the full model. Additionally, we expanded the scope of imputation by developing reference panels for non‐classical, MICA, MICB and HLA‐H genes, previously unavailable for multi‐ethnic populations. Validation in an independent Brazilian dataset showcased the superiority of our reference panels over the Michigan Imputation Server, particularly in predicting HLA‐B alleles among Brazilians. Our investigations underscored the need to enhance or adapt reference panels to encompass the target population's genetic diversity, emphasising the significance of multiethnic references for accurate imputation across different populations. [ABSTRACT FROM AUTHOR]

In an era of increasing urbanization across the planet, understanding how urbanization affects biodiversity and whether or not species will be able to adapt quickly enough to urban environments is critical to conserving biodiversity. We studied the effects of urbanization on genetic diversity, genetic structure, and local adaptation in Tillandsia aeranthos , an epiphytic self-incompatible bromeliad with a high ability to colonize urban habitats. We sampled T. aeranthos along two transects comprising urbanization gradients in South Brazil. We used AFLP markers to genotype 200 individuals and we obtained 971 fragments, of which 100% were polymorphic. We found high levels of genetic diversity and a greater proportion of genetic variation found within populations. We did not find a decrease in genetic diversity with increasing urbanization, as expected if the effects of genetic drift were greater in those urbanized habitats. In each transect, the urban populations were genetically clustered with the non-urban populations, indicating that dispersion by pollen or seed may occur between urban and non-urban populations. The lack of correlation between the outlier loci detected and the index of urbanization found in our study corroborates with other indices of genetic diversity not being affected by urbanization. Our results suggest that gene flow via pollen and seed, combined with high rates of outcrossing, are major determinants of the maintenance of genetic diversity in urban populations of T. aeranthos. [ABSTRACT FROM AUTHOR]

The two species of Montrichardia (Araceae) are perennial herbs of great ecological, economic, and ethnobotanical importance that form populations by clonal growth and sexual reproduction. Here, genetic diversity was studied within a drainage system distant from Amazonia. Five populations were sampled from the Rio Parnaíba Delta (northeast Brazil) and two outside it. The eight ISSR primers selected generated 342 marker bands. The non‐Delta populations (M. arborescens) were grouped together by cluster analysis and Bayesian simulation but the Delta populations (M. linifera) were only grouped weakly. Ordination and Bayesian simulation grouped populations into three pairs along an east–west axis. All population pairs were significantly different (pairwise PhiPT, p ≤ 0.001). Between‐population variance (AMOVA, 39.9% variance, p < 0.001) was much greater than between‐species (12.2%, p < 0.034), but within‐population variance was greatest (48.0%). Within the Delta, geographical distance between populations did not predict genetic similarity, but relative within‐population diversity appears to be influenced by habitat differences. There is genetic evidence, but relatively weak, for recognizing the Delta populations as M. linifera and the non‐Delta ones as M. arborescens; Paulino Neves (Maranhão) appears to be the easternmost record for this species. The strong between‐population differences previously reported for M. linifera are corroborated. [ABSTRACT FROM AUTHOR]

The drug-resistant temporal lobe epilepsy (TLE) has recently been associated with single nucleotide variants (SNVs) in microRNA(miR)-146a (MIR-146A) (rs2910164) and Sodium Voltage-Gated Channel Alpha Subunit 1 (SCN1A) (rs2298771 and rs3812718) genes. Moreover, no studies have shown an association between these SNVs and susceptibility to drug-resistant and drug-responsive TLE in Brazil. Thus, deoxyribonucleic acid (DNA) samples from 120 patients with TLE (55 drug-responsive and 65 drug-resistant) were evaluated by real-time polymerase chain reaction (RT-PCR). A total of 1171 healthy blood donor individuals from the Online Archive of Brazilian Mutations (ABraOM, from Portuguese Arquivo Brasileiro On-line de Mutações), a repository containing genomic variants of the Brazilian population, were added as a control population for the studied SNVs. MIR-146A and SCN1A relative expression was performed by quantitative RT-PCR (qRT-PCR). The statistical analysis protocol was performed using an alpha error of 0.05. TLE patient samples and ABraOM control samples were in Hardy–Weinberg equilibrium for all studied SNVs. For rs2910164, the frequencies of the homozygous genotype (CC) (15.00% vs. 9.65%) and C allele (37.80% vs. 29.97%) were superior in patients with TLE compared to controls with a higher risk for TLE disease [odds ratio (OR) = 1.89 (95% confidence interval (95%CI) = 1.06–3.37); OR = 1.38 (95%CI = 1.04–1.82), respectively]. Drug-responsive patients also presented higher frequencies of the CC genotype [21.81% vs. 9.65%; OR = 2.58 (95%CI = 1.25–5.30)] and C allele [39.09% vs. 29.97%; OR = 1.50 (95%CI = 1.01–2.22)] compared to controls. For rs2298771, the frequency of the heterozygous genotype (AG) (51.67% vs. 40.40%) was superior in patients with TLE compared to controls with a higher risk for TLE disease [OR = 2.42 (95%CI = 1.08–5.41)]. Drug-resistant patients presented a higher AG frequency [56.92% vs. 40.40%; OR = 3.36 (95%CI = 1.04–17.30)] compared to the control group. For rs3812718, the prevalence of genotypes and alleles were similar in both studied groups. The MIR-146A relative expression level was lower in drug-resistant compared to drug-responsive patients for GC (1.6 vs. 0.1, p-value = 0.049) and CC (1.8 vs. 0.6, p-value = 0.039). Also, the SCN1A relative expression levels in samples from TLE patients were significantly higher in AG [2.09 vs. 1.10, p-value = 0.038] and GG (3.19 vs. 1.10, p-value < 0.001) compared to the AA genotype. In conclusion, the rs2910164-CC and rs2298771-AG genotypes are exerting significant risk influence, respectively, on responsive disease and resistant disease, probably due to an upregulated nuclear factor kappa B (NF-kB) and SCN1A loss of function. [ABSTRACT FROM AUTHOR]

Acacia mearnsii De Wild. (Black wattle) is a forest species with great social and economical importance for the southern region of Brazil. This species has multifunctional characteristics, being cultivated to produce tannin, cellulose and energy. This research identified black wattle genotypes with competence for adventitious rooting for mini-cutting propagation. Single-bud mini-cuttings were treated with IBA at a concentration of 2000 mg L-1. After 30 days of cultivation in a humid chamber, the mini-cuttings were evaluated for percentages of survival, rooting, number of roots, average length of the three largest roots, and the number of mini-cuttings rooted per mini-stump. The identification of the best genotypes was performed with the Selegen REML/BLUP software. Selection between and within black wattle progenies can be performed based on the number of rooted mini-cuttings, making it possible to select genotypes with high competence for adventitious rooting while maintaining genetic variability for new selection cycles to develop clones for vegetative propagation by mini-cutting. [ABSTRACT FROM AUTHOR]

Habitat fragmentation is among the greatest threats to arachnids present in the forests, especially to Enoploctenus cyclothorax (Ctenidae), which is widely distributed in the Atlantic Forest of southern and southeastern Brazil. Fragmented populations, whether due to anthropic or stochastic factors, tend to be more susceptible to extinction, since genetic diversity is reduced in small and isolated populations. Considering this, the current work aimed to understand how the genetic variability is distributed in six populations of E. cyclothorax (120 individuals sampled), sampled in fragments of the Atlantic Forest in Paraná (Brazil), based on Single Nucleotide Polymorphism (SNP) genotyping. The results obtained support the separation of E. cyclothorax into two distinct genetic groups in the state, based mainly on analyses of genetic structure and connectivity. A strong and significant genetic structure was observed in the species, supported by the k = 3 estimated using Bayesian analysis, by the high values of FST genetic differentiation, and by the low gene flow identified between the genetic groups. Corroborating these results, isolation by distance and the presence of a genetic barrier in the evaluated populations were evidenced. Population genomic analysis also revealed non-homogeneous genetic diversity in E. cyclothorax (HE = 0.14 to 0.31). The hypothesis that population fragmentation could possibly impact the genetic variability of E. cyclothorax throughout the state was confirmed by the inferred data, which point to phytophysiognomy, geographical distance, and forest fragmentation as factors that shaped the current genetic structure identified in the evaluated populations. [ABSTRACT FROM AUTHOR]

The present study aimed to determine the genetic diversity of isolates of Mycobacterium tuberculosis (Mtb) from presumed drug-resistant tuberculosis patients from several states of Brazil. The isolates had been submitted to conventional drug susceptibility testing for first- and second-line drugs. Multidrug-resistant (MDR-TB) (54.8%) was the most frequent phenotypic resistance profile, in addition to an important high frequency of pre-extensive resistance (p-XDR-TB) (9.2%). Using whole-genome sequencing (WGS), we characterized 298 Mtb isolates from Brazil. Besides the analysis of genotype distribution and possible correlations between molecular and clinical data, we determined the performance of an in-house WGS pipeline with other online pipelines for Mtb lineages and drug resistance profile definitions. Sub-lineage 4.3 (52%) was the most frequent genotype, and the genomic approach revealed a p-XDR-TB level of 22.5%. We detected twenty novel mutations in three resistance genes, and six of these were observed in eight phenotypically resistant isolates. A cluster analysis of 170 isolates showed that 43.5% of the TB patients belonged to 24 genomic clusters, suggesting considerable ongoing transmission of DR-TB, including two interstate transmissions. The in-house WGS pipeline showed the best overall performance in drug resistance prediction, presenting the best accuracy values for five of the nine drugs tested. Significant associations were observed between suffering from fatal disease and genotypic p-XDR-TB (p = 0.03) and either phenotypic (p = 0.006) or genotypic (p = 0.0007) ethambutol resistance. The use of WGS analysis improved our understanding of the population structure of MTBC in Brazil and the genetic and clinical data correlations and demonstrated its utility for surveillance efforts regarding the spread of DR-TB, hopefully helping to avoid the emergence of even more resistant strains and to reduce TB incidence and mortality rates. [ABSTRACT FROM AUTHOR]

Balantioides coli is a ciliated protist that can cause dysentery in humans, pigs and nonhuman primates and may have the potential for zoonotic transmission. Its diagnosis is routinely performed through conventional parasitological techniques, and few studies have used culturing techniques to isolate it, applying molecular tools for the characterization of this protozoan. Thus, the objective of this study was to confirm B. coli diagnosis using molecular tools and to characterize the genetic variants of this parasite isolated from pigs kept on family farms in Brazil using three different culture media that differed in the serum added. Fecal samples from pigs were inoculated in Pavlova medium plus coconut water (PC), fetal bovine serum (PB) and horse serum (PH). Of the 127 samples positive for forms compatible with the phylum Ciliophora, 31 were selected for isolation. The most successful medium for isolation was PB 19/31 (61.3%), followed by PH 18/31 (58.1%) and PC 11/31 (35.5%). Of the nucleotide sequences generated, 20 were classified as genetic variant type B0, two as A1 and 15 as A0. The results indicated that PC, despite having allowed the isolation of B. coli for a short period, was not an adequate medium for the maintenance of this parasite in vitro, therefore requiring improvement. [ABSTRACT FROM AUTHOR]

The selection pressure imposed by the host immune system impacts on hepatitis B virus (HBV) variability. This study evaluates HBV genetic diversity, nucleos(t)ide analogs resistance and HBsAg escape mutations in HBV patients under distinct selective pressures. One hundred and thirteen individuals in different phases of HBV infection were included: 13 HBeAg-positive chronic infection, 9 HBeAg-positive chronic hepatitis, 47 HBeAg-negative chronic infection (ENI), 29 HBeAg-negative chronic hepatitis (ENH) and 15 acute infected individuals. Samples were PCR amplified, sequenced and genetically analyzed for the overlapping POL/S genes. Most HBV carriers presented genotype A (84/113; 74.3%), subgenotype A1 (67/84; 79.7%), irrespective of group, followed by genotypes D (20/113; 17.7%), F (8/113; 7.1%) and E (1/113; 0.9%). Clinically relevant mutations in polymerase (tL180M/M204V) and in the Major Hydrophilic Region of HBsAg (sY100C, T118A/M, sM133T, sD144A and sG145R) were observed. Our findings, however, indicated that most polymorphic sites were located in the cytosolic loops (CYL1-2) and transmembrane domain 4 (TMD4) of HBsAg. Lower viral loads and higher HBV genetic diversity were observed in ENI and ENH groups (p < 0.001), suggesting that these groups are subjected to a higher selective pressure. Our results provide information on the molecular characteristics of HBV in a diverse clinical setting, and may guide future studies on the balance of HBV quasispecies at different stages of infection. [ABSTRACT FROM AUTHOR]

Epstein–Barr virus (EBV) is a ubiquitous gammaherpesvirus etiologically associated with benign and malignant diseases. Since the pathogenic mechanisms of EBV are not fully understood, understanding EBV genetic diversity is an ongoing goal. Therefore, the present work describes the genetic diversity of the lytic gene BZLF1 in a sampling of 70 EBV-positive cases from southeastern Brazil. Additionally, together with the genetic regions previously characterized, the aim of the present study was to determine the impact of viral genetic factors that may influence EBV genetic diversity. Accordingly, the phylogenetic analysis of the BZLF1 indicated two main clades with high support, BZ-A and BZ-B (PP > 0.85). Thus, the BZ-A clade was the most diverse clade associated with the main polymorphisms investigated, including the haplotype Type 1 + V3 (p < 0.001). Furthermore, the multigene phylogenetic analysis (MLA) between BZLF1 and the oncogene LMP1 showed specific clusters, revealing haplotypic segregation that previous single-gene phylogenies from both genes failed to demonstrate. Surprisingly, the LMP1 Raji-related variant clusters were shown to be more diverse, associated with BZ-A/B and the Type 2/1 + V3 haplotypes. Finally, due to the high haplotypic diversity of the Raji-related variants, the number of DNA recombination-inducing motifs (DRIMs) was evaluated within the different clusters defined by the MLA. Similarly, the haplotype BZ-A + Raji was shown to harbor a greater number of DRIMs (p < 0.001). These results call attention to the high haplotype diversity of EBV in southeast Brazil and strengthen the hypothesis of the recombinant potential of South American Raji-related variants via the LMP1 oncogene. [ABSTRACT FROM AUTHOR]

Wheat stripe mosaic virus (WhSMV) is the causal agent of soilborne wheat mosaic disease (SBWMD) in Brazil, which is a serious threat to wheat production in the southern part of the country. WhSMV also occurs in Paraguay and South Africa. The virus is soilborne, transmitted by Polymyxa graminis, and management strategies are mainly based on genetic resistance. Variation in the reaction (type and severity of symptoms) of cultivars has been reported depending on the region and/or year of cultivation, leading wheat breeding programmes to test their materials in several locations, which increases costs and is time‐consuming. One hypothesis is that this variation in symptoms is a result of the genetic variability of WhSMV. We assessed the genetic variability and population structure of WhSMV infecting wheat in Brazil and South Africa. In field experiments conducted in different locations in southern Brazil, a consistent reproducibility of symptoms was observed in a set of cultivars, and molecular analysis showed a low degree of genetic variability of the Brazilian viral population. The hypothesis that the variation in SBWMD symptoms in Brazil is due to genetic variability of the virus was thus rejected. Comparison of the Brazilian and South African WhSMV isolates indicated that they comprise distinct subpopulations and that the Brazilian subpopulation is more variable than the South African subpopulation. The lower genetic variability of the South African subpopulation suggests genetic stability or a recent emergence of WhSMV in that region. [ABSTRACT FROM AUTHOR]

Brazil is recognized for its biodiversity and the genetic variability of its organisms. This genetic variability becomes even more valuable when it is properly documented and accessible. Understanding bacterial diversity through molecular characterization is necessary as it can improve patient treatment, reduce the length of hospital stays and the selection of resistant bacteria, and generate data for health and epidemiological surveillance. In this sense, in this study, we aimed to understand the biodiversity and molecular epidemiology of carbapenem-resistant bacteria in clinical samples recovered in the state of Rondônia, located in the Southwest Amazon region. Retrospective data from the Central Public Health Laboratories (LACEN/RO) between 2018 and 2021 were analysed using the Laboratory Environment Manager Platform (GAL). Seventy-two species with carbapenem resistance profiles were identified, of which 25 species carried at least one gene encoding carbapenemases of classes A (blaKPC-like), B (blaNDM-like, blaSPM-like or blaVIM-like) and D (blaOXA-23-like, blaOXA-24-like, blaOXA-48-like, blaOXA-58-like or blaOXA-143-like), among which we will highlight Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, Serratia marcescens, and Providencia spp. With these results, we hope to contribute to the field by providing epidemiological molecular data for state surveillance on bacterial resistance and assisting in public policy decision-making. [ABSTRACT FROM AUTHOR]

Aims Investigated and compared the occurrence of virulence genes fimH, mrkD, irp2, entB, cps, rmpA , and wabG , resistance genes bla KPC and bla NDM, and the genetic variability and clonal relationship of 29 Klebsiella pneumoniae clinical isolates of patients with and without COVID-19, from a hospital in Brazil. Methods and results All isolates were resistant to beta-lactams. The genes were investigated by PCR, and for molecular typing, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and MLST were used. The detection of bla NDM was greater (n  = 23) when compared to that of bla KPC (n  = 14). The virulence genes that most occurred were fimH, entB, cps , and wabG , which are responsible for adhesins, siderophore enterobactin, capsule, and lipopolysaccharides, respectively. Among the isolates, 21 distinct genetic profiles were found by ERIC-PCR, with multiclonal dissemination. Four isolates belonged to the ST11 clone. Conclusions The occurrence of the ST11 is worrying as it is a high-risk clone involved in the dissemination of virulent strains throughout the world. [ABSTRACT FROM AUTHOR]

Outbreaks of bacterial leaf blight (BLB) frequently affect eucalypt plants under nursery and field conditions in several countries. Although research has been conducted to unveil the causal agent, different bacterial species have been associated with similar disease symptoms in different countries. In order to determine the causal agent of BLB in Brazil, a survey was conducted in nine states to recover bacterial isolates from eucalypt plants exhibiting typical BLB symptoms. A total of 41 yellow‐colony isolates with varying aggressiveness towards a susceptible eucalypt clone were obtained, with 16S rDNA sequences indicating that they belong to the Xanthomonas genus. Rep‐PCR analysis separated the Xanthomonas population affecting eucalypt into six distinct groups revealing its high genetic diversity. The same population formed three clusters together with reference strains of X. citri, X. euvesicatoria and X. phaseoli in a phylogenetic tree constructed with partial dnaK, fyuA, gyrB and rpoD gene sequences. Clustering in the phylogenetic tree was clearly related to grouping based on rep‐PCR. Genome sequence comparisons of representative eucalypt isolates with type strains of validly published Xanthomonas species confirmed that the population consisted of X. citri, X. euvesicatoria and X. phaseoli. Inoculation of tomato, common bean, castor bean and eucalypt plants showed that the representative eucalypt isolates can cause disease in these plant species. Based on the results, the transfer of Xanthomonas axonopodis pv. eucalyptorum to Xanthomonas citri is proposed. These results are relevant for eucalypt BLB management under nursery and field conditions, including selection and deployment of effective plant resistance. [ABSTRACT FROM AUTHOR]

The African fig fly (AFF) Zaprionus indianus Gupta, 1970, is an invasive species that has caused significant damage to several monoculture crops since its introduction in the Brazilian territory, resulting losses for farmers and decrease of fruit productions. A way to manage fruit pests is the chemical control, which could act as a selective pressure against genetic variation in the insect populations. The esterases are detoxifying enzymes that can respond to the selection by insecticides, they are conserved in evolution, and are involved in the hydrolysis of esters, including insecticide degradation. Esterases can be identified by isoenzyme electrophoresis, which is a valuable tool for genetic, biochemical, and ecological studies, particularly in approaches with pest species. This experimental study aimed to evaluate survival and esterase polymorphisms at the Est2 and Est3 loci in three different geographical populations of Z. indianus from Brazil (Aracaju, Uberaba and Florianópolis) after exposition to organophosphate malathion. We identified patterns of sex‐specific genetic variation that indicate a response to insecticide exposition. These results indicated that the insecticide biological response in this species is sex‐dependent, providing relevant information about the AFF‐malathion interaction. This study may contribute to the development of more effective and sustainable management strategies for AFF control in Brazil using genetic and ecological approaches. [ABSTRACT FROM AUTHOR]

Anadenanthera colubrina (Acol) and Anadenanthera peregrina (Aper) (Fabaceae) are two species popularly known as "angicos" that occur in seasonally dry tropical forest (SDTR) remnants in Brazil. Since many of the morphological characteristics of Anadenanthera species are superimposed and species-specific characteristics are difficult to observe, their identification is complex. Therefore, in this research, a set of ISSR (Inter-Simple Sequence Repeat Polymorphic DNA) molecular markers was standardized, aiming to characterize A. colubrina and A. peregrina species and study the genetic diversity of three populations of each species located within a fragmented landscape in São Paulo State, southeastern Brazil. Seven ISSR markers (UBC 2, 820, 851, 858, 864, 866, and 886) that show polymorphism for both species were used. The Bayesian cluster, PCoA and dendrogram analysis show that the total sample divides into two groups corresponding to each species. Also, a genetic divergence (Gst = 0.143) and a high number of migrants per generation (Nm = 3.0) were detected between them. The Acol populations showed significantly higher values for mean genetic diversity (h = 0.30) than Aper (h = 0.25) (p < 0.05). The ISSR marker UBC2250bp showed species-specific electrophoretic fingerprints for both species. The molecular tools generated herein support the conservation of Anadenanthera sp. and the restoration of vegetation where the species naturally occurs. [ABSTRACT FROM AUTHOR]

Simple Summary: We used 46 individuals of the critically endangered Brazilian Merganser, currently endemic to the Cerrado biome in Brazil, to understand genetic diversity and the genealogical relationships of the captive population. By characterizing 425 genomic variants in these captive specimens, our study unveiled a significant level of inbreeding, with approximately 70% of the captive birds tracing their lineage back to the founders from just two localities. Leveraging the identified DNA variants, we also identified less inbred individuals suitable for the potential future reintroduction into the wild. The Brazilian Merganser (Mergus octosetaceus) is one of the rarest birds in South America, and it is a critically endangered Anatidae species with an estimated population of less than 250 adult individuals in the Brazilian Cerrado. A captive population was established a few years ago at Zooparque Itatiba (São Paulo state) where 46 individuals were kept, and the founding population (progenitors derived from nature) was composed of 19 of the ex situ birds, derived from the four remaining localities with wild populations in Brazil. To characterize the genetic diversity and the genealogical relationships of the captive population, it is essential to conduct appropriate ex situ management and to assist future reintroduction projects. Thus, we have identified 425 SNPs by massively parallel sequencing of ddRAD libraries that allowed us to genotype individuals of the captive population. We observed a close relatedness between 70% of the captive population and founding individuals of Jalapão and Alto Paranaiba localities, indicating the need for supplementation with individuals from other areas of Canastra and Veadeiros. Even though many captives present a high level of inbreeding, we have identified some individuals with a high genetic value (less inbred) that can be selected for the breeding program to generate individuals for a future pilot reintroduction project. [ABSTRACT FROM AUTHOR]

Background and Aims: The genetic epidemiology of inherited neuropathies in children remains largely unknown. In this study, we specifically investigated the genetic profile of a Brazilian cohort of pediatric patients with pure or complex axonal neuropathies, a crucial knowledge in the near future for establishing treatment priorities and perspectives for this group of patients. Methods: Fifty‐three pediatric patients who were assessed prior to reaching the age of 20, and who had clinical diagnoses of axonal hereditary neuropathy or presented with axonal neuropathy as the primary clinical feature, were included in the study. The recruitment of these cases took place from January 1, 2018, to December 31, 2020. The diagnosis was based on clinical and electrophysiological data. A molecular assessment was made using target‐gene panel or whole‐exome sequencing. Subsequently, segregation analysis was performed on available family members, and all candidate variants found were confirmed through Sanger. Results: A molecular diagnosis was reached in 68% of the patients (n = 36/53), considering only pathogenic and probably pathogenic variants. Variants in MFN2 (n = 15) and GJB1 (n = 3) accounted for half of the genetically confirmed patients (50%; n = 18/36). The other 18 genetically diagnosed patients had variants in several less common genes. Interpretation: Apart from MFN2 and GJB1 genes, universally recognized as a frequent cause of axonal neuropathies in most studied population, our Brazilian cohort of children with axonal neuropathies showed an important genetic heterogeneity, probably reflecting the multi ethnicity of the Brazilian population. Diagnostic, counseling, and future interventions should consider this characteristic. [ABSTRACT FROM AUTHOR]

This study investigated the prevalence and genetic diversity of gastroenteric viruses in mussels and oysters in Rio de Janeiro, Brazil. One hundred and thirty-four marketed bivalve samples were obtained between January and December 2022. The viral analysis was performed according to ISO/TS 15216, and the screening revealed the detection of norovirus GII/GI (40.3%), sapovirus (SaV; 12.7%), human mastadenovirus (7.5%), and rotavirus A (RVA; 5.9%). In total, 44.8% (60) of shellfish samples tested positive for one or more viruses, 46.7% (28/60) of the positive samples tested positive for a single viral agent, 26.7% (16) tested positive for two viral agents, 8.3% (5) for three viral agents, and 13.3% (8) for four viral agents. Additionally, three mussel samples were contaminated with the five investigated viruses (5%, 3/60). Norovirus GII showed the highest mean viral load (3.4 × 105 GC/g), followed by SaV (1.4 × 104 GC/g), RVA (1.1 × 104 GC/g), human mastadenovirus (3.9 × 103 GC/g), and norovirus GI (6.7 × 102 GC/g). Molecular characterization revealed that the recovered norovirus strains belonged to genotypes GII.2, GII.6, GII.9, GII.17, and GII.27; SaV belonged to genotypes GI.1 and GIV.1; RVA to genotypes G6, G8, P[8]-III, and human mastadenovirus to types F40 and F41. The GII.27 norovirus characterized in this study is the only strain of this genotype reported in Brazil. This study highlights the dissemination and diversity of gastroenteric viruses present in commercialized bivalves in a touristic area, indicating the potential risk to human health and the contribution of bivalves in the propagation of emerging pathogens. [ABSTRACT FROM AUTHOR]

Microcephaly presents heterogeneous genetic etiology linked to several neurodevelopmental disorders (NDD). Copy number variants (CNVs) are a causal mechanism of microcephaly whose investigation is a crucial step for unraveling its molecular basis. Our purpose was to investigate the burden of rare CNVs in microcephalic individuals and to review genes and CNV syndromes associated with microcephaly. We performed chromosomal microarray analysis (CMA) in 185 Brazilian patients with microcephaly and evaluated microcephalic patients carrying < 200 kb CNVs documented in the DECIPHER database. Additionally, we reviewed known genes and CNV syndromes causally linked to microcephaly through the PubMed, OMIM, DECIPHER, and ClinGen databases. Rare clinically relevant CNVs were detected in 39 out of the 185 Brazilian patients investigated by CMA (21%). In 31 among the 60 DECIPHER patients carrying < 200 kb CNVs, at least one known microcephaly gene was observed. Overall, four gene sets implicated in microcephaly were disclosed: known microcephaly genes; genes with supporting evidence of association with microcephaly; known macrocephaly genes; and novel candidates, including OTUD7A, BBC3, CNTN6, and NAA15. In the review, we compiled 957 known microcephaly genes and 58 genomic CNV loci, comprising 13 duplications and 50 deletions, which have already been associated with clinical findings including microcephaly. We reviewed genes and CNV syndromes previously associated with microcephaly, reinforced the high CMA diagnostic yield for this condition, pinpointed novel candidate loci linked to microcephaly deserving further evaluation, and provided a useful resource for future research on the field of neurodevelopment. [ABSTRACT FROM AUTHOR]

In this study, we analysed the molecular and morphometric differences of several populations of the putative sand fly vector Psychodopygus davisi (Root, 1934) (Diptera, Psychodidae, Phlebotominae) in Brazil. We amplified the 658 base pair fragments of the DNA barcoding region—cytochrome c oxidase subunit 1 (COI) gene—for 57 specimens of P. davisi and three specimens of Psychodopygus claustrei (Abonnenc, Léger & Fauran, 1979). We merged our data with public sequences of the same species available from GenBank. Then, the combined dataset—87 sequences and 20 localities—was analysed using population structure analysis and different species delimitation approaches. Geometric morphometry of wings was performed for 155 specimens of P. davisi populations from the North, Midwest and Southeast Brazilian regions, analysing the differences in centroid sizes and canonical variates. Molecular analysis indicated high intraspecific genetic distance values for P. davisi (maximum p distance = 5.52%). All algorithms identified P. davisi and P. claustrei as distinct molecular taxonomic units, despite the low interspecific distance (p distance to the nearest neighbour = 4.79%). P. davisi sequences were split into four genetic clusters by population structure analysis and at least five genetic lineages using intermediate scenarios of the species delimitation algorithms. The species validation analysis of BPP strongly supported the five‐species model in our dataset. We found high genetic diversity in this taxon, which is in agreement with its wide geographic distribution in Brazil. Furthermore, the wing analysis showed that specimens from the Southeast Region of Brazil are different from those in the North and the Midwest. The evolutionary patterns of P. davisi populations in Brazil suggest the presence of candidate species, which need to be validated in future studies using a more comprehensive approach with both genomic data and morphological characters. [ABSTRACT FROM AUTHOR]

The Caatinga biogeographical region, located in the semi-arid region of northeastern Brazil, is characterized by high levels of cactus diversity and endemism. In this study, we investigated the genetic diversity, differentiation, and phylogeography of three Tacinga species (Tacinga inamoena , Tacinga subcylindrica , and Tacinga palmadora), which are endemic and widely distributed in the Caatinga. We collected 222 samples from 108 locations and used plastid (3 ʹ rps16-5 ʹ trnK , PsbE-PetL) and nuclear (PhyC) molecular markers for a multilocus approach. Our results suggest that diversification of the three Tacinga species occurred during the middle Pleistocene, with the Southern Sertaneja Depression ecoregion of the Caatinga being identified as the ancestral area. Interestingly, analyses of genetic structure did not show any evidence that the major river in the region (the Sao Francisco River) and the Caatinga ecoregions acted as biogeographical barriers for gene flow in these species. This suggests that the three Tacinga species exhibited different responses to widely accepted geographical and geomorphological barriers known to affect other taxonomic groups in the Caatinga. Overall, our findings provide new insights into the biogeographical history of the Caatinga and the factors that have shaped diversification and genetic structure of species in this region. Our study underlines the importance of considering the unique natural history and biological characteristics of individual taxonomic groups when investigating the biogeography of the Caatinga. [ABSTRACT FROM AUTHOR]

The soybean bud borer, a soybean pest in Brazil, was initially identified as Crocidosema aporema (Walsingham 1914) (Lepidoptera: Tortricidae). Outbreaks of this species have recently increased, but identification of this pest remains uncertain, and the historical factors associated with its geographic distribution in Brazil are little known. Here, we conducted a species characterization and phylogeographic analysis based on molecular and morphological evidence. Ninety individuals of bud-borers Lepidoptera were collected in different regions of Brazil. We sequenced COI and COII mitochondrial genes and examined wing patterns and male genital morphology. DNA barcoding approach revealed that 10 individuals were Argyrotaenia sphaleropa (Meyrick 1909) (Lepidoptera: Tortricidae) and 80 were a species of the genus Crocidosema Zeller. The morphology of the adult genitalia and wings proved to be insufficient to confirm the identification of Brazilian individuals as C. aporema , a species originally described from a high-elevation site in Costa Rica. Furthermore, the genetic distance between putative C. aporema specimens from Brazil and Costa Rica (ranging from 5.2% to 6.4%) supports the hypothesis that the Brazilian specimens are not referable to C. aporema. Our analysis revealed a single genetic strain (i.e. species) with low genetic diversity on soybean crops. We found no indication that the genetic structure was related to geographic distance among populations or edaphoclimatic regions. The population expansion of the soybean bud borer coincides with the increase in the area of soybean production in Brazil, suggesting that expanded soybean farming has allowed a significant increase in the effective population size of this pest. [ABSTRACT FROM AUTHOR]

Unusual colorations are rare in Didelphis, but records are important to understand genetic aspects of the species. Albino individuals have a total absence of pigmentation throughout the body (skin and hair) and have eyes without traces of pigmentation, but with a red or pink color. We draw attention to the first two confirmed records of albinism in white-eared opossum (Didelphis albiventris) and their karyotype. This is the first record of albinism in D. albiventris in Northeastern Brazil. This calls attention to develop future research on the genetic diversity and the risk of inbreeding and consanguinity in populations of this region. [ABSTRACT FROM AUTHOR]

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An in-depth genotypic characterisation of a diverse collection of Digitaria insularis was undertaken to explore the neutral genetic variation across the natural expansion range of this weed species in Brazil. With the exception of Minas Gerais, populations from all other states showed high estimates of expected heterozygosity (HE > 0.60) and genetic diversity. There was a lack of population structure based on geographic origin and a low population differentiation between populations across the landscape as evidenced by average Fst value of 0.02. On combining haloxyfop [acetyl CoA carboxylase (ACCase)-inhibiting herbicide] efficacy data with neutral genetic variation, we found evidence of presence of two scenarios of resistance evolution in this weed species. Whilst populations originating from north-eastern region demonstrated an active role of gene flow, populations from the mid-western region displayed multiple, independent resistance evolution as the major evolutionary mechanism. Atarget-site mutation (Trp2027Cys) in the ACCase gene, observed in less than 1% of resistant populations, could not explain the reduced sensitivity of 15% of the populations to haloxyfop. The genetic architecture of resistance to ACCase-inhibiting herbicides was dissected using a genome wide association study (GWAS) approach. GWAS revealed association of three SNPs with reduced sensitivity to haloxyfop and clethodim. In silico analysis of these SNPs revealed important non-target site genes belonging to families involved in herbicide detoxification, including UDPGT91C1 and GT2, and genes involved in vacuolar sequestration-based degradation pathway. Exploration of five genomic prediction models revealed that the highest prediction power (≥0.80) was achieved with the models Bayes A and RKHS, incorporating SNPs with additive effects and epistatic interactions, respectively. [ABSTRACT FROM AUTHOR]

Fusarium wilt caused by Fusarium oxysporum f. sp. cubense (Foc) is one of the most destructive diseases in banana farming worldwide. Knowledge of the factors of genetic diversity and virulence of the pathogen contributes to the development of resistant cultivars and management strategies based on exclusion. In this study, phenotypic traits such as virulence and aggressiveness in a sample of 52 Foc isolates were analyzed and their relationship to the presence of putative effectors of gene SIX (Secreted in Xylem) pathogenicity homologs was verified. The similarity matrix revealed three isolates that were closest to the standard Foc race 1 strain. Isolates 229A and 218A were selected according to their aggressiveness profile in 'Grand Naine' and 'Prata-Anã', respectively, to replace the standard isolate of race 1 in the resistance screening process carried out by the breeding program. Two homologs of the SIX8 gene, SIX8a and SIX8b, are present in isolates of Foc from Brazil, and the SIX8b gene correlates with avirulence in the cultivar 'Grand Naine' (Cavendish). These results are important to support the banana genetic breeding program by identifying sources of resistance to Foc and contributing to the establishment of the function of SIX effector proteins. [ABSTRACT FROM AUTHOR]

The biogeographic history of a species results from responses to past and current processes, and understanding those responses at both temporal scales is essential. We explored phylogeographic and current genetic variation structure in Ctenomys flamarioni —a subterranean rodent that inhabits a small region of the coastal plain of Brazil—and contrasted the roles of "present-day niche suitability" versus "historical climate stability" to understand current and past intraspecific genetic diversity. We used both mitochondrial DNA sequences (concatenated Cytb and D-loop , n = 78) and nuclear DNA (9 microsatellites loci, n = 154) molecular markers for individuals across the entire distribution of the species. We used phylogeographic trees, Bayesian clustering, and haplotype networks to explore genetic variation and diversity. We correlated genetic diversity with measures of current niche suitability and potential areas of Late Quaternary paleostability. Phylogeographic patterns confirmed low levels of genetic diversity structured at different hierarchical levels. We also found a weak but significant pattern of isolation by distance, indicating that geographical distance partially modulates genetic differences among populations. We also observed a positive correlation between genetic diversity and climate paleostability for microsatellites at local and regional scales. However, we found no significant association between genetic diversity and niche suitability for microsatellites at local or regional scales. We observed several signatures of bottleneck and population expansion at different geographic scales. Our results suggest that Quaternary climatic fluctuations—acting together with habitat suitability and other contemporary factors—played a fundamental role in elucidating the evolutionary history of the species—including patterns of historical dispersal, and current patterns of habitat occupation and genetic structure. In addition, based on our molecular and environmental data sets from the across the range of the species and considering the restricted endemism of C. flamarioni , we emphasize the urgency of conservation actions to protect this endangered species. [ABSTRACT FROM AUTHOR]

The genus Mentha spp. is an aromatic herb from the family 'Lamiaceae'. It is extensively predominant in temperate and sub-temperate regions of the world. The essential oil of this species is enriched with broad aroma constituents extensively utilized in food, beverages, flavor, cosmetics, perfumery, and pharmaceutical enterprises. With the global menthol market size estimated to be worth USD 765 million in 2022, India (accompanied by China and Brazil) is the world's primary manufacturer, consumer, and exporter of Mentha oil. Despite prominent global demand, the crucial bottleneck in mint cultivation is the need for more superior commercial cultivars. Predominant vegetative propagation mode with difficulties in manual emasculation, differential blooming times, sterile/sub-sterile hybrids, and low seed viability are the primary containment in creating genetic variability by classical breeding approaches. Therefore, genetic complications encountered in conventional breeding have led the breeders to apply mutation breeding as an alternative crop improvement approach in Mentha spp. These attempts at mutation breeding have produced some distinctive mutants as genetic pools for plant breeding programs, and some novel mutant mint cultivars have been made available for commercial cultivation. The prime strategy in mutation-based breeding has proven an adept means of encouraging the expression of recessive genes and producing new genetic variations. The present review comprises a significant contribution of mutation breeding approaches in the development of mutant mint species and its effects on physiological variation, photosynthetic pigment, essential oil content and composition, phytochemical-mediated defense response, pathogen resistivity, and differential expression of genes related to terpenoid biogenesis. Development and diversification have led to the release of varieties, namely Todd's Mitcham, Murray Mitcham, Pranjal, Tushar, and Kukrail in M. piperita L., Mukta, and Pratik in M. cardiaca Baker, Neera in M. spicata L., Kiran in M. citrata Ehrh., and Rose mint in M. arvensis L. that have revolutionized and uplifted mint cultivation leading to economic gain by the farmers and entrepreneurs. [ABSTRACT FROM AUTHOR]

The condition known as 22q11.2 deletion syndrome (MIM #188400) is a rare disease with a highly variable clinical presentation including more than 180 features; specific guidelines for screening individuals have been used to support clinical suspicion before confirmatory tests by Brazil's Craniofacial Project. Of the 2568 patients listed in the Brazilian Database on Craniofacial Anomalies, 43 individuals negative for the 22q11.2 deletion syndrome were further investigated through whole-exome sequencing. Three patients (6.7%) presented with heterozygous pathogenic variants in the KMT2A gene, including a novel variant (c.6158+1del) and two that had been previously reported (c.173dup and c.3241C>T); reverse phenotyping concluded that all three patients presented features of Wiedemann–Steiner syndrome, such as neurodevelopmental disorders and dysmorphic facial features (n = 3), hyperactivity and anxiety (n = 2), thick eyebrows and lower-limb hypertrichosis (n = 2), congenital heart disease (n = 1), short stature (n = 1), and velopharyngeal insufficiency (n = 2). Overlapping features between 22q11.2 deletion syndrome and Wiedemann–Steiner syndrome comprised neuropsychiatric disorders and dysmorphic characteristics involving the eyes and nose region; velopharyngeal insufficiency was seen in two patients and is an unreported finding in WDSTS. Therefore, we suggest that both conditions should be included in each other's differential diagnoses. [ABSTRACT FROM AUTHOR]

Recent molecular studies have clarified the overarching taxonomy of capuchin monkeys, but intraspecific genetic diversity remains unexplored for most capuchin species. One example is Sapajus nigritus, the southernmost capuchin monkey, found in Brazil and Argentina; its phenotypic diversity has been recognized as two geographic subspecies, but the intraspecific genetic structure of this taxon is poorly known. Here, we sampled across most of this species' geographic distribution, producing a newly sequenced data set for genetic analyses that included 78 individuals from 14 populations. We investigated the intraspecific diversity, genetic structure, and evolutionary history using three mitochondrial markers. Our results indicated that S. nigritus populations exhibited high levels of genetic structure. We found strong support for two monophyletic clades within this species with a deep phylogenetic split, and clear separation from other related taxa. Vicariance events seem to have played a prevalent role in shaping S. nigritus genetic differentiation. The Paraíba do Sul River may have driven the deep divergence between southern and northern clades, whereas the Tietê River may have had a weaker, more recent effect on the divergence of populations within the southern clade. Research Highlights: Using mitochondrial markers we found support for two major clades within Sapajus nigritus; the Paraíba do Sul River probably acted as a barrier to drive this deep phylogenetic split, estimated to have occurred at 1.56 MaWe recovered the southern S. nigritus clade as sister to a clade of other Sapajus species (S. cay, apella, macrocephalus, robustus, flavius) rather than northern S. nigritus, emphasizing southern and northern clades as distinct phylogenetic unitsS. nigritus D‐loop analysis showed high pairwise populational genetic differentiation and geographic structure; this D‐loop database can now be used for to help identify the geographical origin of illegally traded animals [ABSTRACT FROM AUTHOR]

Recurrent selection is an effective breeding method for improving complex traits in wheat (Triticum aestivum L.) breeding. In this study, we propose a genitor selection strategy, employing a multi‐trait selection approach and genetic diversity analysis. To evaluate our proposed method, we conducted a lattice design trial during the winter seasons of 2020 and 2021 in Viçosa, MG, Brazil, comprising 87 lines and 13 commercial cultivars. It assessed various traits such as plant height, days to heading, wheat leaf rust, tan spot of wheat, a hundred grain mass, hectoliter weight, and grain yield, and the best linear unbiased predictor (BLUP) was obtained for each trait via restricted maximum likelihood. Next, a genotypic distance matrix, derived from principal component analysis using the BLUP values, was computed to perform hierarchical clustering via the unweighted pair group method with arithmetic mean. The selection of superior genotypes was made utilizing the multi‐trait genotype‐ideotype distance index, resulting in the identification of eight lines and two commercial cultivars as candidates. Furthermore, the genetic diversity analysis revealed distinct clusters among the selected genotypes. To assess the divergence of the chosen genitors, this study proposes a complementarity matrix using factor analysis. Our results indicate that this selection strategy effectively directed the identification of the best and divergent genitors. The complementarity matrix developed in this paper to evaluate the crossings proposal can also be used to evaluate combinations in any panel selected via a multi‐trait approach and can be easily applied and interpreted by breeders of various programs. Core Ideas: Novel strategy to select divergent genitors for cycle zero of recurrent selection program is presented.Multi‐trait selection and genetic diversity analysis of tropical wheat on phenotypic data is presented.A complementarity index based on a factor analysis is presented to evaluate the proposed crossings. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii is an intracellular parasite with a worldwide distribution. Toxoplasma gondii infections are of great concern for public health, and their impact is usually most severe in pregnant women and their foetuses, and in immunocompromised individuals. Displaying considerable genetic diversity, T. gondii strains differ widely according to geographical location, with archetypal strains predominantly found in the Northern Hemisphere and non-archetypal (atypical) strains, with highly diverse genotypes, found mainly in South America. In this review, we present an overview of the identification and distribution of non-archetypal strains of T. gondii. Special attention is paid to the strains that have been isolated in Brazil, their interaction with the host immunological response, and their impact on disease outcomes. The genetic differences among the strains are pivotal to the distinct immunological responses that they elicit. These differences arise from polymorphisms of key proteins released by the parasite, which represent important virulence factors. Infection with divergent non-archetypal strains can lead to unusual manifestations of the disease, even in immunocompetent individuals. [ABSTRACT FROM AUTHOR]

Simple Summary: The Brazilian merganser, a critically endangered duck species in South America, was studied using a population genomics approach. This research focused on the genetic diversity of the mergansers in the four remaining wild populations located in Central Brazil. The results showed that there is a low genetic diversity and high levels of inbreeding in individuals across all locations, with a moderate level of genetic differentiation between them. These findings highlight the need for immediate conservation actions to prevent the decline of the Brazilian merganser population and genetic erosion. Genetic monitoring can help implement appropriate in situ and ex situ management strategies to increase the species' long-term survival in its natural environment. The Brazilian merganser (Mergus octosetaceus) is one of the most endangered bird species in South America and comprises less than 250 mature individuals in wild environments. This is a species extremely sensitive to environmental disturbances and restricted to a few "pristine" freshwater habitats in Brazil, and it has been classified as Critically Endangered on the IUCN Red List since 1994. Thus, biological conservation studies are vital to promote adequate management strategies and to avoid the decline of merganser populations. In this context, to understand the evolutionary dynamics and the current genetic diversity of remaining Brazilian merganser populations, we used the "Genotyping by Sequencing" approach to genotype 923 SNPs in 30 individuals from all known areas of occurrence. These populations revealed a low genetic diversity and high inbreeding levels, likely due to the recent population decline associated with habitat loss. Furthermore, it showed a moderate level of genetic differentiation between all populations located in four separated areas of the highly threatened Cerrado biome. The results indicate that urgent actions for the conservation of the species should be accompanied by careful genetic monitoring to allow appropriate in situ and ex situ management to increase the long-term species' survival in its natural environment. [ABSTRACT FROM AUTHOR]

Background: Wild boars (Sus scrofa) may cause substantial damage to crops and can spread zoonotic parasites to domestic animals, posing a risk to health and animal production. Metastrongylus spp. can negatively affect the wild boar population, increasing piglet mortality. In addition to that, studies with Metastrongylus genetic characterization are still scarce in Brazil. The present study aims to characterize Metastrongylus spp. from wild boars hunted in the states of São Paulo, Paraná, and Rio Grande do Sul, Brazil, using traditional morphological description and DNA sequences in an integrative taxonomic approach. Methods: After nematode collection from 58 wild boars, the parasites were morphologically identified and genetically characterized by the amplification of 18S ribosomal DNA (rDNA), 28S rDNA, internal transcribed spacer (ITS) region, and cox-1 mitochondrial DNA (mtDNA). Descriptors of infection were determined and Pearson's Chi-square test was applied to compare the prevalence of infections among the identified parasite species, host age group (juveniles and adults), and sex. The Mann–Whitney U test was performed to compare the mean intensity between the age groups and sex. Results: Metastrongylus salmi, Metastrongylus apri, and Metastrongylus pudendotectus were identified in 77.6% (45/58) of the necropsied wild boars. Metastrongylus salmi was the most prevalent and abundant species (70.7%, 11.1), followed by M. pudendotectus (18.9%, 4.3) and M. apri (17.2%, 2.2). Metastrongylus pudendotectus showed the highest mean intensity and range (25.2, 1–93), followed by M. salmi (15.7, 1–58) and M. apri (12.6, 3–27). We found a significantly higher prevalence of Metastrongylus spp. and M. salmi in adult wild boars, probably associated with a more prolonged time of exposure to intermediate host species. The phylogenetic analysis revealed that ITS2 region and cox-1 mtDNA are the most suitable genetic markers for Metastrongylus species characterization. Genetic variability between M. apri and M. salmi isolates was verified. Conclusions: We expand the knowledge about the Metastrongylus community in the non-captive wild boar population from Brazil as well as the importance of this exotic species in the maintenance of Metastrongylus spp. in its areas of occurrence. The novel genetic sequences obtained may help further studies to understand the genetic diversity in other nematode populations from Brazil and other countries. [ABSTRACT FROM AUTHOR]