High Heritability Research Articles

Scald resistance in hybrid rye (Secale cereale): genomic prediction and GWAS.

Rye (Secale cereale L.) is an important cereal crop used for food, beverages, and feed, especially in North-Eastern Europe. While rye is generally more tolerant to biotic and abiotic stresses than other cereals, it still can be infected by several diseases, including scald caused by Rhynchosporium secalis. The aims of this study were to investigate the genetic architecture of scald resistance, to identify genetic markers associated with scald resistance, which could be used in breeding of hybrid rye and to develop a model for genomic prediction for scald resistance. Four datasets with records of scald resistance on a population of 251 hybrid winter rye lines grown in 2 years and at 3 locations were used for this study. Four genomic models were used to obtain variance components and heritabilities of scald resistance. All genomic models included additive genetic effects of the parental components of the hybrids and three of the models included additive-by-additive epistasis and/or dominance effects. All models showed moderate to high broad sense heritabilities in the range of 0.31 (SE 0.05) to 0.76 (0.02). The model without non-additive genetic effects and the model with dominance effects had moderate narrow sense heritabilities ranging from 0.24 (0.06) to 0.55 (0.08). None of the models detected significant non-additive genomic variances, likely due to a limited data size. A genome wide association study was conducted to identify markers associated with scald resistance in hybrid winter rye. In three datasets, the study identified a total of twelve markers as being significantly associated with scald resistance. Only one marker was associated with a major quantitative trait locus (QTL) influencing scald resistance. This marker explained 11-12% of the phenotypic variance in two locations. Evidence of genotype-by-environment interactions was found for scald resistance between one location and the other two locations, which suggested that scald resistance was influenced by different QTLs in different environments. Based on the results of the genomic prediction models and GWAS, scald resistance seems to be a quantitative trait controlled by many minor QTL and one major QTL, and to be influenced by genotype-by-environment interactions.

Identification of potential elephant grass hybrids for forage production via mixed models

Elephant grass has been widely used as forage because it is easier to become silage and because it has good nutritional indices. This research aimed to estimate the combining ability and analyze the genetic components of elephant grass (Pennisetum purpureum Schum. syn. Cenchrus purpureus) hybrids got from diallel crosses. Twenty-five elephant grass hybrids were obtained by a 5 x 5 partial diallel design, which were evaluated, at three harvests (January 2013, July 2013, and January 2014). Plants were grown in the field for three months before each harvest, taken for two harvests in the wet season (October to January) and one harvest in the dry season (May to July). The experiments were carried out in a randomized block design with 3 replications. Diallel analyzes were performed using a mixed model approach. There was high environment variance and low narrow-sense heritability for most traits. Narrow-sense heritability estimates were higher than 0.5 for leaf blade width. The combinations UENF38 x UENF3, UENF49 x UENF3, UENF49 x UENF37, UENF60 x UENF3 were selected for higher forage yield.

Early-onset familial essential tremor is associated with nucleotide expansions of spinocerebellar ataxia in China.

Essential tremor (ET) is a neurological disease characterized by action tremor in upper arms. Although its high heritability and prevalence worldwide, its etiology and association with other diseases are still unknown. We investigated 10 common spinocerebellar ataxias (SCAs), including SCA1, SCA2, SCA3, SCA6, SCA7, SCA8, SCA12, SCA17, SCA36, dentatorubral-pallidoluysian atrophy (DRPLA) in 92 early-onset familial ET pedigrees in China collected from 2016 to 2022. We found one SCA12 proband carried 51 CAG repeats within PPP2R2B gene and one SCA3 proband with intermediate CAG repeats (55) with ATXN3 gene. The other 90 ET probands all had normal repeat expansions. Tremor can be the initial phenotype of certain SCA. For early-onset, familial ET patients, careful physical examinations are needed before genetic SCA screening.

Genetic parameters, trends, and inbreeding in a honeybee breeding program for royal jelly production and behavioral traits

An economically sustainable production of royal jelly (RJ) requires the use of genetics specifically improved for this very demanding trait. The French Royal Jelly Association has developed since 2010 a selection plan for that purpose, based on a collective data recording system and the initial seedstock of five French beekeepers. The aim of this study was to evaluate the efficiency of this collective breeding program, a decade after its concrete start. We considered three different genetic models to describe the phenotypes, hereafter named the Colony, Worker, and Queen Models. We showed that when the size and the structure of the dataset are insufficient to fit a Colony Model, fitting a Queen Model gives more understandable results for practical use of the estimated breeding values than the Worker Model. Regarding genetic parameters, we estimated moderate to high heritability values for all traits, regardless of the genetic model. Under a Queen Model, heritability estimates of RJ production were 0.19 ± 0.09 and 0.35 ± 0.13 for first and second harvests, respectively; the estimates were 0.76 ± 0.08, 0.29 ± 0.09, and 0.22 ± 0.08, respectively, for the calmness, gentleness, and spring development of the colony. We also proved that the breeding program is efficient, increasing the production at second harvest of 3.5% per year on average. Attention must, however, be paid to the evolution of inbreeding in this very small breeding population. Few genetic correlations were significantly different from zero between the traits, due to large standard errors of our estimates. It is, however, worth to note that the trends were generally favorable between all traits, which appears encouraging to improve production and behavioral traits jointly in the breeding program.

Genetic Variability, Heritability, Genetic Advance and Association Studies in Blackgram [Vigna mungo (L.) Hepper

Background: In Tamil Nadu blackgram is cultivated in 4.02 lakhs hectare with the production of 2.25 millon tonnes and productivity of 559 kg/ha. Even though it has great importance, blackgram cultivation is ignored as minimum attention is given towards its genetic improvement. There are various reasons for the low production of crop like lack of genetic variability, absence of suitable ideotype, susceptibility to biotic and abiotic stresses and planting in marginal areas of farming. Hence, it is important to improve the productivity of blackgram. Methods: The present investigation was carried out on 44 blackgram genotypes at field experimentation site of Regional Research Station, Tamil Nadu Agricultural University, Aruppukkottai, Virudhunagar District, to study genetic variability, heritability, genetic advance and correlation and path effects of seven important yield contributing traits including yield trait. Result: Highest GCV and PCV value observed for seed yield per plant and for plant height. High heritability coupled with high genetic advance as percent of mean were recorded for plant height and seed yield (kg/ha) and selection of these traits was useful for further improvement in plant breeding programme. Association analysis revealed that seed yield exhibited significant and positive correlated with plant height and number of pods/plant. Yield component traits viz., plant height, number of pods/plant, 100 seed weight and single plant yield were highly correlated among themselves. It was observed that plant height and number of pod/plant had the maximum positive direct effects on seed yield. The indirect effect of plant height on grain yield was positive through days to maturity, days to fifty percent flowering and number of pods per plant. Hence selection of plants based on plant height and number of pods/plant will help the improvement of seed yield in blackgram.

Quantitative 2D fruit shape analysis of a wide range of pear genetic resources toward shape design breeding

The shape of a fruit is one of the main characteristics of fruit morphology, and its quantitative description is crucial to improve fruit quality. However, the shape of a pear fruit is relatively complex, and difficult to describe comprehensively. This study aimed to quantitatively analyze the morphological diversity of 2D fruit shapes of 276 cultivars, covering 6 groups including Pyrus pyrifolia, Pyrus bretschneideri, Pyrus ussuriensis, Pyrus sinkiangensis, Pyrus communis and interspecific hybridization, and discover shape traits with high heritability. Through an automated image processing method, the fruit contour was first accurately extracted, and then geometrical parameters and Fourier descriptors of the pear fruit shape were obtained. Furthermore, principal components (PCs) of the Fourier descriptors were analyzed, and the broad-sense heritability (H2) of the PCs and standardized width (WSD) were estimated. After that, the pear shape stability was calculated, and cultivars were clustered by their shape characteristics. This paper mainly discusses the longitudinal section, as the cross-section variation among cultivars is small. For the longitudinal section, the results showed more than 95 % of the two-dimensional shape variation can be explained by only six principal components; WSD20, WSD30 and PC1 have high H2; the shape stability of western pear was the lowest; a new class of shape was found by clustering the shape traits. The results indicated that the proposed pipeline can provide an objective and comprehensive quantitative description of pear fruit shape for a wide range of cultivars, which is necessary to discover the key genes determining pear shape. This approach is also beneficial for research on pear breeding and germplasm resource management.

Genetic variability, heritability and correlation in chrysanthemum (<i>Dendranthema grandiflora</i>)

Chrysanthemum is a herbaceous perennial flowering crop that holds great potential for commercial cultivation. Fifteen chrysanthemum genotypes were studied at the Department of Floriculture and Landscaping, College of Agriculture, Vellanikkara, Kerala Agricultural University, Thrissur, Kerala during 2022 for variability studies in morphological, flowering and post-harvest parameters. Significant variations were recorded among the genotypes for all the traits. Cluster analysis grouped the 15 chrysanthemum genotypes into 4 clusters based on all the characters. Cluster 2 consists of maximum number of 5 genotypes followed by 4 genotypes each in cluster 3 and cluster 4. Highest intra-cluster distance was recorded for cluster 2 and highest inter-cluster distance was observed between cluster 1 and 4. Results revealed that GCV was greater than the equivalent PCV, indicating that the environment had a negligible influence on phenotypic variation. High heritability coupled with high genetic advance for all the characters, indicating additive gene effect suggests that there is excellent scope for selection and improvement. Flower yield per plant showed a substantial positive correlation with flowers/plant, flower diameter, stalk length, stalk girth and flower weight at both phenotypic and genotypic level which could be focused for yield improvement.

Fruit Quality Assessment of Novel Hybrid Pummelo × Sweet Orange and Its Molecular Characterization Using Acidity Specific Markers.

There is considerable diversity in newly developed pummelo × sweet orange citrus hybrids. Most hybrids showed lower peel thickness and high juice yield but there is a lack of information on fruit quality parameters and molecular characterization. Therefore, the aim of the current study is to determine the content of antioxidants and properties of the fresh juice of 24 new pummelo × sweet orange citrus hybrids (Citrus maxima [Burm. f.] Osbeck × Citrus sinensis [L.] Osbeck) and the parental genotypes along with molecular characteristics determined using acidity specific markers. The correlation and estimate of inheritance of the fruit juice properties: ascorbic acid, total phenol, total flavonoid, total antioxidant, total soluble solid and sugar contents, pH, titratable acidity, along with sensory evaluation was performed. Molecular characterization of these hybrids was carried out using de novo generated acidity specific simple sequence repeat (SSR) markers. The main constituents of the fruit juice of pummelo × sweet orange hybrids were observed in the range of w(ascorbic acid)=40.00-58.13 mg/100 g, total phenols expressed as gallic acid equivalents w(GAE)=40.67-107.33 mg/100 g, total antioxidants expressed as Trolox equivalents b(Trolox)=2.03-5.49 µmol/g, total flavonoids expressed as quercetin equivalents w(QE)=23.67-59.33 mg/100 g, along with other properties: total soluble solids=7.33-11.33 %, w(total sugar)=2.10-5.76 %, w(reducing sugar)=1.69-2.78 %, w(non-reducing sugar)=0.39-3.17 % and titratable acidity 1.00-2.11 %. The above parameters differed significantly in the fruit juice of the evaluated pummelo × sweet orange hybrids. Considering these parameters, the hybrids SCSH 17-9, SCSH 13-13, SCSH 11-15 and SCSH 3-15 had superior antioxidant properties in terms of these parameters. A higher heritability (≥80 %) was also observed for all juice properties. Molecular characterization of pummelo × sweet orange hybrids showed that >50 % of the hybrids were grouped with medium acidity parents. Both molecular and biochemical parameter-based clustering showed that interspecific hybrids exhibit transgressive segregation with increased antioxidants that help alleviate the health problems. These newly developed pummelo × sweet orange citrus hybrids are a valuable source of high-quality antioxidants for a healthy diet. The identification of trait markers that enable selection at the seedling stage is of great benefit to citrus breeders, as the characteristic features of a mature tree are not yet visible at the juvenile stage.

Identification of the shared genetic architecture underlying seven autoimmune diseases with GWAS summary statistics.

The common clinical symptoms and immunopathological mechanisms have been observed among multiple autoimmune diseases (ADs), but the shared genetic etiology remains unclear. GWAS summary statistics of seven ADs were downloaded from Open Targets Genetics and Dryad. Linkage disequilibrium score regression (LDSC) was applied to estimate overall genetic correlations, bivariate causal mixture model (MiXeR) was used to qualify the polygenic overlap, and stratified-LDSC partitioned heritability to reveal tissue and cell type specific enrichments. Ultimately, we conducted a novel adaptive association test called MTaSPUsSet for identifying pleiotropic genes. The high heritability of seven ADs ranged from 0.1228 to 0.5972, and strong genetic correlations among certain phenotypes varied between 0.185 and 0.721. There was substantial polygenic overlap, with the number of shared SNPs approximately 0.03K to 0.21K. The specificity of SNP heritability was enriched in the immune/hematopoietic related tissue and cells. Furthermore, we identified 32 pleiotropic genes associated with seven ADs, 23 genes were considered as novel genes. These genes were involved in several cell regulation pathways and immunologic signatures. We comprehensively explored the shared genetic architecture across seven ADs. The findings progress the exploration of common molecular mechanisms and biological processes involved, and facilitate understanding of disease etiology.

Correlation and Path Analysis for Fiber Yield and Its Constituent Component Characters in Jute Mallow (Corchorus olitorius L.)

The research work was conducted at the BCKV, research station in Mohanpur, Nadia, West Bengal in 2020, thirty jute genotypes were evaluated for fibre yield and related traits. It was revealed that 14 yield-related characters, such as basal diameter, bark thickness after 120 DAS, plant height, green weight plant-1, node number plant-1, and internodes length, showed moderate genetic advance and high heritability. These traits were found to be significantly different. Plant height, node number plant-1, internode length, basal diameter, petiole length, leaf area, bark thickness, green weight plant-1, chlorophylls 'a' and 'b', and total chlorophyll, as well as dry stick weight plant-1, all displayed a significantly positive correlation with dry fibre weight at both the phenotypic and genotypic levels. The path coefficient analysis results showed that node number plant-1, internode length, plant height, basal diameter, petiole length, bark thickness both at 90 DAS and 120 DAS, chlorophyll 'b' and total chlorophyll had significant direct effects on dry fibre yield. These characters should be taken into consideration as important selection criteria to increase the yield of fibre in tossa jute.

UNVEILING GENETIC THREADS: PHENOTYPIC EXPLORATION OF CHICKPEA (CICER ARIETINUM L.) GERMPLASMS FOR HERITABILITY AND TRAIT ASSOCIATIONS

The second most important self-pollinating legume crop in the world is the chickpea. Chickpea is an inexpensive source of protein that grows well in various climates. The current study aimed to evaluate the genetic advance and heritability of different characters at the seedling stage by analyzing their phenotypic attributes. During the 2022–2023 growing season, a randomized complete block design experiment was set up in the University of the Punjab's field area. The experiment included five different germplasms. At the seedling stage, data from seven morphological parameters were collected. ANOVA and correlation were performed using Statistix software. Seedling length, root length, and root-shoot ratio have shown low genotypic coefficients of variation (GCV) and phenotypic coefficients of variation (PCV), indicating a high environmental effect on these traits. Root length and leaf width had shown a strong correlation with seedling length. Path coefficient analysis directly affected root length and leaf width towards seedling length. Low genetic advance and high heritability were observed in root length, seedling length and root-shoot ratio, meaning selection should be delayed for one or more generations for such traits. Leaf width and leaf area have shown high heritability and genetic advance, suggesting that selecting such characters may lead to superior variety development based on phenotype.

Multi-Trait Selection Index for Simultaneous Selection of Water Yam (Dioscorea alata L.) Genotypes

Water yam (Dioscorea alata L.) is the most widely cultivated yam species with good agronomic attributes. However, several biotic and abiotic constraints and its lower food quality such as poor pound ability limit its production and use. Therefore, the identification of superior genotypes with suitable characteristics is needed for water yam improvement. This study aims to assess a panel of half-sib (progenies with one parent in common) and full-sib (progenies with the same male and female parents) progenies as well as their parents for selection of desirable ideotypes based on their agronomic and quality characteristics. A total of 280 progenies from bi-parental populations as well as five parents were evaluated, and a significant variation was observed (p < 0.01) in their performances for the eight traits used in the study. A moderate to high broad-sense heritability (30% < H2–H2 ≥ 60%) was observed for all traits except for tuber pound ability (H2 < 30%). Positive correlations were displayed between the traits, while the hierarchical clustering grouped genotypes into three clusters indicating the potential for selection of diverse genotypes for multiple traits from the four families under study. Plant vigor and number of tubers per plant contributed (p < 0.01) positively to the yield per plant in the path coefficient analysis. Using the multi-trait genotype–ideotype distance index (MGIDI), a total of 39 most promising genotypes were identified. These promising genotypes could be further used as progenitors in D. alata improvement programs targeting good agronomic and quality traits targeted for farmers and end users.

Studies on genetic variability and heritability in bulb onion (Allium cepa L.) in the South-Eastern plains of Bihar, India

The study was conducted at Vegetable Research Farm, Department of Horticulture, Bihar Agricultural University, Sabour, Bhagalpur during Rabi season 2021-22 with the objective to study genetic variability in onion (Allium cepa L.) for yield and yield attributing traits. The experimental material consisted of 15 onion genotypes from different locations in India. Experimental trial was laid out in a RBD with three replications. Analysis of variance was done by the method suggested by Panse and Sukhatme (1967). The observations were recorded on five randomly selected plants of all genotypes for plant height, number of leaves, leaf length, leaf width, pseudostem length, neck thickness, polar diameter, equatorial diameter, and average bulb weight. Analysis of variance indicated significant differences among the genotypes for all the characters under study which implied a considerable amount of genetic variability in the genotypes included in the study. The highest average weight of onion bulb was recorded in genotype LC-1 (62.13g) which was statistically at par with LC-2 (58.53g), Patna Red (57.80g), Bhima Shakti (57.28 g) and Agrifound Light Red (56.87g). High PCV and GCV were recorded for pseudostem length and neck thickness. Moderate GCV and PCV were found in leaf width, average bulb weight, plant height, leaf length, equatorial diameter and bulb size index. High heritability along with high genetic advance as percentage of mean was exhibited by all the morphological traits. The genotypes LC-1, LC-2, Patna Red and Bhima Shakti were identified as promising ones for the yield and yield contributing traits.

Genetic analysis of stay green related traits in maize with major gene plus polygenes mixed model.

Maize is one of the main food crops in the world, and cultivating high-yield and high-quality maize varieties is of great significance in addressing food security issues. Leaves are crucial photosynthetic organs in maize, and leaf senescence can result in the degradation of chlorophyll. This, in turn, impacts photosynthetic activity and the accumulation of photosynthetic products. Delaying leaf senescence and increasing carbon assimilation can enhance grain yield and biomass production. The stay green of maize is an important trait closely related to yield, feed quality and resistance. Therefore, this study employed multi-generation joint analysis of major genes and a polygene model to investigate the genetic inheritance of stay green-related traits. Four populations (P1, P2, F1 and F2) were obtained by crossing T01 (stay green) × Xin3 (non-stay green) and T01 (stay green) × Mo17 (non-stay green) under two environments. Six stay green-related traits, including visual stay green (VSG), number of green leaves (GLNM), SPAD value of ear leaf at anthesis (SPADS), SPAD value of ear leaf at maturity (SPADM), absolute green leaf area (GLAD), grain yield per plant (GYP), displayed continuous variations with kurtosis and skewness values of absolute value less than 1 and distribution close to normal. They were characterized by typical inheritance of quantitative traits, with these traits demonstrating the transgressive segregation. The correlation analysis among the traits revealed that five stay green traits have a positive impact on yield. VSG, GLNM and SPADM in the two populations were regulated by the two major genes of additive effects plus additive-dominance polygene model with a major gene heritability varying from 89.03 to 95.95% in the F2 generation. GLAD in TMF2 was controlled by two major genes of equal-additive dominance effects with high heritability (93.47%). However, in TXF2, GLAD was regulated by two major genes of additive-dominance interaction effects plus additive-dominance polygene model. These results provide important genetic information for breeding, which could guide the improvement of stay green-related traits. They also lay a foundation for quantitative trait loci mapping of the stay stay-green traits in maize.

Identification of a Predictive Model for Schizophrenia Based on SNPs in a Chinese Population.

Schizophrenia is a devastating mental disease with high heritability. A growing number of susceptibility genes associated with schizophrenia, as well as their corresponding SNPs loci, have been revealed by genome-wide association studies. However, using SNPs as predictors of disease and diagnosis remains difficult. Here, we aimed to uncover susceptibility SNPs in a Chinese population and to construct a prediction model for schizophrenia. A total of 210 participants, including 70 patients with schizophrenia, 70 patients with bipolar disorder, and 70 healthy controls, were enrolled in this study. We estimated 14 SNPs using published risk loci of schizophrenia, and used these SNPs to build a model for predicting schizophrenia via comparison of genotype frequencies and regression. We evaluated the efficacy of the diagnostic model in schizophrenia and control patients using ROC curves and then used the 70 patients with bipolar disorder to evaluate the model's differential diagnostic efficacy. 5 SNPs were selected to construct the model: rs148415900, rs71428218, rs4666990, rs112222723 and rs1716180. Correlation analysis results suggested that, compared with the risk SNP of 0, the risk SNP of 3 was associated with an increased risk of schizophrenia (OR = 13.00, 95% CI: 2.35-71.84, p = 0.003). The ROC-AUC of this prediction model for schizophrenia was 0.719 (95% CI: 0.634-0.804), with the greatest sensitivity and specificity being 60% and 80%, respectively. The ROC-AUC of the model in distinguishing between schizophrenia and bipolar disorder was 0.591 (95% CI: 0.497-0.686), with the greatest sensitivity and specificity being 60% and 55.7%, respectively. The SNP risk score prediction model had good performance in predicting schizophrenia. To the best of our knowledge, previous studies have not applied SNP-based models to differentiate between cases of schizophrenia and other mental illnesses. It could have several potential clinical applications, including shaping disease diagnosis, treatment, and outcomes.

Investigating the shared genetic architecture between breast and ovarian cancers.

High heritability and strong correlation have been observed in breast and ovarian cancers. However, their shared genetic architecture remained unclear. Linkage disequilibrium score regression (LDSC) and heritability estimation from summary statistics (ρ-HESS) were applied to estimate heritability and genetic correlations. Bivariate causal mixture model (MiXeR) was used to qualify the polygenic overlap. Then, stratified-LDSC (S-LDSC) was used to identify tissue and cell type specificity. Meanwhile, the adaptive association test called MTaSPUsSet was performed to identify potential pleiotropic genes. The Single Nucleotide Polymorphisms (SNP) heritability was 13% for breast cancer and 5% for ovarian cancer. There was a significant genetic correlation between breast and ovarian cancers (rg=0.21). Breast and ovarian cancers exhibited polygenic overlap, sharing 0.4 K out 2.8 K of causal variants. Tissue and cell type specificity displayed significant enrichment in female breast mammary, uterus, kidney tissues, and adipose cell. Moreover, the 74 potential pleiotropic genes were identified between breast and ovarian cancers, which were related to the regulation of cell cycle and cell death. We quantified the shared genetic architecture between breast and ovarian cancers and shed light on the biological basis of the co-morbidity. Ultimately, these findings facilitated the understanding of disease etiology.

Deciphering the genetic variability for biochemical parameters influencing rancidity of pearl millet (Pennisetum glaucum L. R. Br.) flour in a set of highly diverse lines and their categorization using rancidity matrix

Pearl millet is renowned for its exceptional nutritional value due to its high concentration of essential nutrients. However, a substantial hurdle hindering its global adoption is the issue of rancidity, which manifests as the development of undesirable odours and flavors in millet flour. The present work aims to evaluate a set of highly diverse 255 accessions for exploring genotypic variations related to biochemical parameters influencing rancidity and their categorization using a rancidity matrix. These parameters include comprehensive acid value (CAV), comprehensive peroxide value (CPV), as well as lipase and lipoxygenase (LOX) enzyme activities under both fresh and stored conditions. High heritability and genetic advance for CPV and LOX under both fresh and stored conditions indicated the presence of additive genetic effects. Positive associations were noted among all the rancidity-related biochemical parameters. Principal component analysis (PCA) further illustrated the positive correlation between CAV and lipase activity, and between CPV and LOX activity. Based on lower values of CAV under fresh conditions and all other biochemical parameters under fresh and stored conditions, lines IP 5695 and IP 19334 were identified as low rancid lines. Additionally, genotypes were categorized into low, medium, and high rancidity groups based on CAV and CPV, providing valuable insights into trait variability. These findings hold significant promise for the development of breeding material, variety and hybrids of pearl millet with longer shelf life and wider utilization.

Aleutian disease: Risk factors and ImmunAD strategy for genetic improvement of tolerance in American mink (Neogale vison).

Aleutian disease (AD) is a devastating infectious disease in American mink (Neogale vison) industry caused by Aleutian mink disease virus (AMDV). Two crucial steps toward controlling infectious diseases in farm animals are: (i) assessment of the infection risk factors to minimize the likelihood of infection and (ii) selection of animals with superior immune responses against pathogens to build tolerant farms. This study aimed to investigate AD risk factors and evaluate a novel "ImmunAD" approach for genetic improvement of AD tolerance. Phenotypic records and pedigree information of 1,366 and 24,633 animals were included in this study. The risk of animal's age, sex, color type, and year of sampling on AMDV infection was assessed using a logistic regression model and counter immune-electrophoresis (CIEP) test results. ImmunAD phenotype was calculated based on AMDVG enzyme-linked immunosorbent assay (ELISA) and CIEP test results, and breeding values for ImmunAD were estimated using an animal model. Animals were classified into high-coordinated (HCIR), average-coordinated (ACIR), and low-coordinated immune responders (LCIR) using ImmunAD's breeding values, and the impact of selection of HCIR on live grade of pelt quality (PQ), harvest weight (HW), and harvest length (HL) breeding values were evaluated. Age of > 1 year, male sex, and year of sampling were identified as significant risk factors of AD (p < 0.05). A moderate-to-high heritability (0.55±0.07) was estimated for ImmunAD, while a higher heritability was observed among the CIEP-positive animals (0.76±0.06). Significantly higher breeding values were observed for PQ and HL among HCIR than those for LCIR and ACIR (p < 0.05). Our findings indicate the critical role of male breeders in AD distribution within mink farms. Regular screening of AD in male breeders before pairing them with females during breeding seasons can help disease control. ImmunAD strategy can be applied to genetic improvement of AD tolerance, with favorable impacts on some growth and production traits. Higher genetic gains can be achieved in populations with higher AD seroprevalences.

Direct Selection Parameter Estimates and Path Coefficient Analysis for Grain Yield and Quantitative Traits in Maize (Zea mays L.)

The study was carried out at the Maize Research Institute “Zemun Polje”, Belgrade, Serbia during 2021 growing season in three location. Six inbred lines were crossed according to complete diallel method. In this way 15 hybrids and 15 reciprocal combinations were obtained. Hybrid and reciprocal combinations derived from these parental components were used in this paper. The present study was carried out to study the variability, broad-sense heritability (H2 bs), genetic advance (GA), correlation among traits, genotypic and phenotypic path analysis among grain yield and its components. The results indicated that the genotypes were significantly different for all traits. For all traits, the phenotypic coefficient of variation was higher than the genotypic coefficient of variation. The highest heritability was found in 1000 kernel weight, followed by grain yield, ear diameter and anthesis-silking interval (ASI). In our study Genetic Advance over Mean (GAM) for the traits ranged from lowest value (9.739%) for cob diameter to the highest value (90.579%) for anthesis-silking interval. According to results of path analysis, the trait 1000 kernel weight with the value of 0.365 has the strongest direct positive effect on grain yield. Positive direct effects on grain yield were also observed for ear length (0.202), ear diameter (0.248) and number of rows per ear (0.076), while negative direct effects were observed for cob diameter (-0.057). The trait 1000 kernel weight had the highest indirect positive effects on grain yield via ear diameter (0.232). The cob diameter had highest negative indirect effect on grain yield via ear diameter (-0.048). Coefficient of multiple determinations (R2) had a value of 0.428. This indicated the important role of additive gene effect in the inheritance of these traits and could be improved through simple selection.

Genetic polymorphisms, biomarkers and signaling pathways associated with septic shock: from diagnosis to therapeutic targets.

Septic shock is a severe form of sepsis characterized by high global mortality rates and significant heritability. Clinicians have long been perplexed by the differential expression of genes, which poses challenges for early diagnosis and prompt treatment of septic shock. Genetic polymorphisms play crucial roles in determining susceptibility to, mortality from, and the prognosis of septic shock. Research indicates that pathogenic genes are known to cause septic shock through specific alleles, and protective genes have been shown to confer beneficial effects on affected individuals. Despite the existence of many biomarkers linked to septic shock, their clinical use remains limited. Therefore, further investigation is needed to identify specific biomarkers that can facilitate early prevention, diagnosis and risk stratification. Septic shock is closely associated with multiple signaling pathways, including the toll-like receptor 2/toll-like receptor 4, tumor necrosis factor-α, phosphatidylinositol 3-kinase/protein kinase B, mitogen-activated protein kinase, nuclear factor κB, Janus kinase/signal transducer and activator of transcription, mammalian target of rapamycin, NOD-like receptor thermal protein domain-associated protein 3 and hypoxia-induced-factor-1 pathways. Understanding the regulation of these signaling pathways may lead to the identification of therapeutic targets for the development of novel drugs to treat sepsis or septic shock. In conclusion, identifying differential gene expression during the development of septic shock allows physicians to stratify patients according to risk at an early stage. Furthermore, auxiliary examinations can assist physicians in identifying therapeutic targets within relevant signaling pathways, facilitating early diagnosis and treatment, reducing mortality and improving the prognosis of septic shock patients. Although there has been significant progress in studying the genetic polymorphisms, specific biomarkers and signaling pathways involved in septic shock, the journey toward their clinical application and widespread implementation still lies ahead.