The intergeneric hybridization between Brassica napus L. cv. oro and Matthiola incana (L.) R. Br. was carried out to study the phytogenetic peculiarities of the hybrid plants. In order to improve the oil quality of ra...The intergeneric hybridization between Brassica napus L. cv. oro and Matthiola incana (L.) R. Br. was carried out to study the phytogenetic peculiarities of the hybrid plants. In order to improve the oil quality of rape seed, ovaries of B. napus pollinated with pollen of M. incana, were cut off and inoculated onto MS media supplemented with various plant hormones at the 7th day after pollination. Two mature embryos were obtained from 750 pollinated ovaries cultured in vitro. The percentage of seed set was 0.26%. The mature embryos were transferred onto the MS media supplemented with 2.0 mg/L 6-BA + 0.1 mg/L NAA, and a compound bud was produced later. The compound bud was then cut into a number of single buds, which were transferred onto fresh media. Twenty-two plantlets in vitro were developed from the above single buds. The hybrid plants (F-1) were basically intermediate between the two parents in many,characters with a few showing hybrid vigor. The fertility of hybrid plants (F-1) was poor. Cytological studies revealed that the hybrid plants (F-1) were mixoploid. in nature. The chromosome number of many somatic cells was 2n = 26, which was the sum of the chromosome number of the two parents. The chromosome number of other somatic cells was 2n = 38, similar to that of B. napus. The hybrid offspring (F-2) from the selfed hybrid plants (F-1) showed polymorphism. Among the hybrid offspring (F-2) some were nearly matroclinous and fertile, similar to B. napus. some others were intermediate between the two parents and less fertile, and a few were poorly developed and nearly infertile. From the hybrid offspring a few plants with improved seed-oil quality were obtained.展开更多
To improve performances of multi-objective optimization algorithms, such as convergence and diversity, a hybridization- encouraged mechanism is proposed and realized in elitist nondominated sorting genetic algorithm ...To improve performances of multi-objective optimization algorithms, such as convergence and diversity, a hybridization- encouraged mechanism is proposed and realized in elitist nondominated sorting genetic algorithm （NSGA-Ⅱ）. This mechanism uses the normalized distance to evaluate the difference among genes in a population. Three possible modes of crossover operators--＂Max Distance＂, ＂Min-Max Distance＂, and ＂Neighboring-Max＂--are suggested and analyzed. The mode of ＂Neighboring-Max＂, which not only takes advantage of hybridization but also improves the distribution of the population near Pareto optimal front, is chosen and used in NSGA-Ⅱ on the basis of hybridization-encouraged mechanism （short for HEM-based NSGA-Ⅱ）. To prove the HEM-based algorithm, several problems are studied by using standard NSGA-Ⅱ and the presented method. Different evaluation criteria are also used to judge these algorithms in terms of distribution of solutions, convergence, diversity, and quality of solutions. The numerical results indicate that the application of hybridization-encouraged mechanism could effectively improve the performances of genetic algorithm. Finally, as an example in engineering practices, the presented method is used to design a longitudinal flight control system, which demonstrates the obtainability of a reasonable and correct Pareto front.展开更多
To achieve germplasm innovation and study genetic variation of important traits of bamboo plants,we used Bambusa multiplex,B.chungii,and Dendrocalamus latiflorus as parent materials for distant and inbred hybridizatio...To achieve germplasm innovation and study genetic variation of important traits of bamboo plants,we used Bambusa multiplex,B.chungii,and Dendrocalamus latiflorus as parent materials for distant and inbred hybridizations.Two hybrid populations and three inbred populations were obtained:two populations consisted of 57 hybrid progenies from B.multiplex 9 B.chungii,26 hybrid progenies from B.multiplex 9 D.latiflorus,and three inbred progenies were from B.multiplex,B.chungii,and D.latiflorus.Traits for growth,morphology,and fiber were examined from the five populations when plants were 3 years old.Two hybrid populations had significant growth advantages in terms of height,diameter at ground level and internodal length.In terms of variability in morphological traits,the two hybrid populations followed the same trend,namely,seven morphological traits showed phenotypes that were intermediate to those of their parents;three morphological traits showed strong maternal effects,and three other morphological traits showed strong paternal effects.Among the five populations,the two hybrid populations had high arithmetic average fiber length,lengthweighted average fiber length and mass-weighted average fiber length,moreover,extensive variations of these three traits were observed within these two hybrid populations.The establishment of distant hybrid populations from these three bamboo species increased the genetic diversity more than in the other species examined.This work provides excellent materials for breeding new varieties and lays the foundation for understanding the genetics of important traits by analyzing related functional genes.展开更多
AIM: To characterize cytogenetic alterations in esophageal squamous cell carcinoma (ESCC) and its metastasis. METHODS: A total of 37 cases of primary ESCC and 15 pairs of primary ESCC tumors and their matched metastat...AIM: To characterize cytogenetic alterations in esophageal squamous cell carcinoma (ESCC) and its metastasis. METHODS: A total of 37 cases of primary ESCC and 15 pairs of primary ESCC tumors and their matched metastatic lymph nodes cases were enrolled from Linzhou, the high incidence area for ESCC in Henan, northern China. The comparative genomic hybridization (CGH) was applied to determine the chromosomal aberrations on the DNA extracted from the frozen ESCC and metastatic lymph node samples from these patients. RESULTS: CGH showed chromosomal aberrations in all the cases. In 37 cases of primary ESCC, chromosomal profile of DNA copy number was characterized by frequently detected gains at 8q (29/37, 78%), 3q (24/37, 65%), 5p (19/37, 51%); and frequently detected losses at 3p (21/37, 57%), 8p and 9q (14/37, 38%). In 15 pairs of primary ESCC tumors and their matched metastatic lymph node cases, the majority of the chromosomal aberrations in both primary tumor and metastatic lymph node lesions were consistent with the primary ESCC cases, but new candidate regions of interest were also detected. The most significant finding is the gains of chromosome 6p with a minimum high-level amplification region at 6p12-6q12 in 7 metastatic lymph nodes butonly in 2 corresponding primary tumors (P = 0.05) and 20p with a minimum high-level amplification region at 20p12 in 11 metastatic lymph nodes but only in 5 corresponding primary tumors (P < 0.05). Another interesting finding is the loss of chromosome 10p and 10q in 8 and 7 metastatic lymph nodes but only in 2 corresponding primary tumors (P < 0.05). CONCLUSION: Using the CGH technique to detect chromosomal aberrations in both the primary tumor and its metastatic lymph nodes of ESCC, gains of 8q, 3q and 5p and loss of 3p, 8p, 9q and 13q were specifically implicated in ESCC in Linzhou population. Gains of 6p and 20p and loss of 10pq may contribute to the lymph node metastasis of ESCC. These findings suggest that the gains and losses of chromosomal regions may contain ESCC-related oncogenes and tumor suppressor genes and provide important theoretic information for identifying and cloning novel ESCC-related oncogenes and tumor suppressor genes.展开更多
Studies on the reproduction and cytogenetic characterization of a primary amphidiploid Cucumis species C. hytivus Chen and Kirkbride (2n = 4x = 38) indicated that a more comprehensive cytogenetic analysis of this spec...Studies on the reproduction and cytogenetic characterization of a primary amphidiploid Cucumis species C. hytivus Chen and Kirkbride (2n = 4x = 38) indicated that a more comprehensive cytogenetic analysis of this species and its first selfed progeny would increase its potential utility in cucumber improvement. With tendrils used as source materials for mitotic analysis, chromosome numbers in all selfed progenies were 2n = 38, confirming chromosomal stability in this synthetic amphidiploid species. Detailed meiotic processes were described by comparing the primary and the selfed amphidiploids. Meiotic abnormalities, such as chromosome lagging, unequal separation, chromosome multi-polarization and polyads were observed frequently in all amphidiploid plants except for the selfed no.8, in which meiosis was arrested prior to metaphase Ⅰ. Generally, the frequency of multivalents was higher and the configurations were more complex in the selfed progenies, demonstrating a more extensive genetic exchange between cucumber and C. hystrix Chakr. Genome separation between cucumber and C. hystrix was observed through prophase Ⅰ to anaphase Ⅰ in both generations of the amphidiploids. Consequently, in addition to n = 19, a new gamete with n = 7 was produced, which was confirmed by the chromosome counts 2n = 14 in the backcrossing progenies from cucumber × amphidiploid mating. Fertility varied among the selfed amphidiploid plants. The selfed plant no.1 was found to have an improved fertility (e.g., pollen staining ability 40.8% and 25.6 seeds per fruit) and then was used as source germplasm in further introgression and gene exchange experiments.展开更多
The genomic structures of Oryza sativa （A genome） and O. meyeriana （G genome） were comparatively studied using bicolor genomic in situ hybridization （GISH）. GISH was clearly able to discriminate between the chro...The genomic structures of Oryza sativa （A genome） and O. meyeriana （G genome） were comparatively studied using bicolor genomic in situ hybridization （GISH）. GISH was clearly able to discriminate between the chromosomes of O. sativa and O. meyeriana in the interspecific F1 hybrids without blocking DNA, and co-hybridization was hardly detected. The average mitotic chromosome length of O. meyeriana was found to be 1.69 times that of O. sativa. A comparison of 4,6-diamidino-2-phenylindole staining showed that the chromosomes of O. meyeriana were more extensively labelled, suggesting that the G genome is amplified with more repetitive sequences than the A genome. In interphase nuclei, 9-12 chromocenters were normally detected and nearly all the chromocenters constituted the G genome-specific DNA. More and larger chromocenters formed by chromatin compaction corresponding to the G genome were detected in the hybrid compared with its parents. During pachytene of the F1 hybrid, most chromosomes of A and G did not synapse each other except for 1-2 chromosomes paired at the end of their arms. At meiotic metaphase I, three types of chromosomal associations, i.e.O, sativa-O, sativa （A-A）, O. sativa-O, meyeriana （A-G） and O. meyeriana-O, meyeriana （G-G）, were observed in the F1 hybrid. The A-G chromosome pairing configurations included bivalents and trivalents. The results provided a foundation toward studying genome organization and evolution of O. meyeriana.展开更多
indica and japonica are the two most important subspecies of Asian cultivated rice. Identifying mechanisms responsible for population differentiation in these subspecies is important for indica-japonica hybridization ...indica and japonica are the two most important subspecies of Asian cultivated rice. Identifying mechanisms responsible for population differentiation in these subspecies is important for indica-japonica hybridization breeding. In this study, subspecies and economic trait differentiation patterns were analyzed using morphological and molecular （InDel and Intron Length Polymorphism） data in F2 and F3 populations derived from indica-japonica hybridization. Populations were grown in Liaoning and Guangdong provinces, China, with F3 populations generated from F2 populations using bulk harvesting （BM） and single-seed descent methods （SSD）. Segregation distortion was detected in F3-BM populations, but not in F3- SSD or in F2 populations. Superior performance was observed with respect to economic traits in Liaoning compared with that in Guangdong and 1 000-grain weight （KW）, seed setting rate （SSR） and grain yield per plant （GYP） were significantly correlated with indica and japonica subspecies types. Analysis of molecular and morphological data demonstrated that the environment is the main factor giving rise to population differentiation in indica-japonica hybridization. In addition, we also found that KW, SSR and GYP are related to subspecies characteristics and kinship, which is possibly a significant factor resulting in economic trait differentiation and determining environmental adaptability. Our study has provided new insights into the process of population differentiation in these subspecies to inform indica-japonica hybridization breeding.展开更多
Congenital scoliosis(CS)is a prevalent spinal deformity with a multifaceted etiology that remains incompletely understood.Recent advances in genetic and epigenetic research have provided novel insights into CS pathoge...Congenital scoliosis(CS)is a prevalent spinal deformity with a multifaceted etiology that remains incompletely understood.Recent advances in genetic and epigenetic research have provided novel insights into CS pathogenesis.Herein,we review the current progress in genetics and epigenetics to examine genetic variants,susceptibility factors,and the epigenetic regulatory mechanisms implicated in CS.Through an analysis of diverse genetic markers,chromosomal abnormalities,and epigenetic modifications,the correlation between genetic predisposition and environmental influences in CS pathogenesis is elucidated.By integrating these genetic and epigenetic findings,this study aims to clarify the underlying etiology of CS to provide guidance on future clinical interventions and promote the development of personalized therapeutic strategies.展开更多
Polyploidization is a commonly employed strategy in crop breeding to augment genetic diversity,particularly leveraging the distinctive benefits of additional progressive heterosis or multi-generation heterosis unique ...Polyploidization is a commonly employed strategy in crop breeding to augment genetic diversity,particularly leveraging the distinctive benefits of additional progressive heterosis or multi-generation heterosis unique to polyploidy.Despite genetic disparities between polyploids and diploids,challenges stem from reproductive anomalies,complicating genetic investigations in polyploid systems.Through nearly two decades of intensive research,our team has effectively generated a series of fertile tetraploid lines known as neo-tetraploid rice(NTR),facilitating comparative genetic studies between diploid and tetraploid rice.In this study,we identified diploid counterparts(H3d and H8d)for two NTR lines[Huaduo 3(H3)and Huaduo 8(H8)]and utilized them to create diploid and tetraploid fertile F_(2) populations to assess genotype segregation ratios,recombination rates,and their impact on QTL mapping via bulked segregant analysis combined with sequencing(BSA-seq).Additionally,we assessed yield heterosis in F_(1) and F_(2) generations of two tetraploid populations(H3×H8 and T449×H1),revealing evidence of multi-generation heterosis in polyploid rice.These findings provide valuable insights into the advantages and challenges of polyploid rice breeding.展开更多
Inflammatory bowel disease(IBD)represents a significant disease burden marked by chronic inflammation and complications that adversely affect patients’quality of life.Effective diagnostic strategies involve clinical ...Inflammatory bowel disease(IBD)represents a significant disease burden marked by chronic inflammation and complications that adversely affect patients’quality of life.Effective diagnostic strategies involve clinical assessments,endoscopic evaluations,imaging studies,and biomarker testing,where early diagnosis is essential for effective management and prevention of long-term complications,highlighting the need for continual advancements in diagnostic methods.The intricate interplay between genetic factors and the outcomes of biological therapy is of critical importance.Unraveling the genetic determinants that influence responses and failures to biological therapy holds significant promise for optimizing treatment strategies for patients with IBD on biologics.Through an indepth examination of current literature,this review article synthesizes critical genetic markers associated with therapeutic efficacy and resistance in IBD.Understanding these genetic actors paves the way for personalized approaches,informing clinicians on predicting,tailoring,and enhancing the effectiveness of biological therapies for improved outcomes in patients with IBD.展开更多
Fluorescence in situ hybridization (FISH) has become an important tool both for defining initial chromosomal abnormalities within a disease process, and for monitoring response to therapy as well as minimal residual d...Fluorescence in situ hybridization (FISH) has become an important tool both for defining initial chromosomal abnormalities within a disease process, and for monitoring response to therapy as well as minimal residual disease. We report the results of interphase FISH (iFISH) analysis of 92 patients. We have used five different FISH probes to detect common cytogenetic rearrangements associated with hematological malignancies. A total of 83 patients were screened for BCR/ABL gene rearrangements. Displayed iFISH patterns of BCR/ABL gene rearrangements in 37.3% of patients (31/83) ranged between 10% to 98%. In addition, while 3 patients and one patient with AML showed t(15;17) (12.5%) and inv(16;16) (8.3%) respectively, t(8;21) was not found. Furthermore, secondary chromosomal aberrations (6.5% of all cases) were clearly non random in the present study. The diagnosis of BCR/ABL gene rearrangements are likely become an important tool for the monitoring of therapies in patients with CML. Atypical patterns also may have clinical prognostic implications. Further studies in larger groups of patients are needed in order to elucidate the role of AML1/ETO, PML/RARA, CBFB and p53, and to identify the specific chromosomal regions and interacting genes involved in this process.展开更多
The mussel is one of the main cultivated species in the world.A significant challenge faced by suspension-cultured mussels is the high incidence of mussel fall-off from cultivation ropes,adversely impacting harvest yi...The mussel is one of the main cultivated species in the world.A significant challenge faced by suspension-cultured mussels is the high incidence of mussel fall-off from cultivation ropes,adversely impacting harvest yields,which have been documented at commercial mussel farms in the United Kingdom,the United States of America,Canada,Spain,New Zealand and China.Byssus is an important attachment structure for marine mussels,and weakness in byssal thread attachment is a major factor leading to mussel detachment from ropes.To investigate the relationship between genetic variability and byssal thread phenotypic characteristics in the hard-shelled mussel(Mytilus coruscus),we collected three wild populations of M.coruscus from different latitudes in the East China Sea,including the Shengsi(SS),Jiaojiang(JJ),and Fuding(FD)populations.The genetic diversity and structure of these populations were investigated using 10 microsatellite loci.The mean observed heterozygosity(Ho)in the SS population was 0.44,higher than the mean Ho values of the JJ(0.40)and FD(0.39)populations.The mean inbreeding coefficients(F_(is))in the SS population was 0.20,lower than the mean F_(is)values of the JJ(0.33)and FD populations(0.40).These results revealed that the SS population exhibited higher genetic diversity compared to the other two populations.The different numbers of private alleles(P_(a))in the three populations,ranging from 10 to 17,suggest that these populations have experienced selective pressures from various environments.Moreover,genetic differentiation was observed in the genetic distance between the SS population and the other two populations.We also examined the phenotypic characteristics of their byssal threads.There were significant differences in byssus attachment strength among the three populations,with the SS population located at the highest latitude secreting more byssal threads and exhibiting greater byssal breaking force and plaque adhesion strength,while the Fuding(FD)population located at the lowest latitude had the weakest byssal attachment.The observed differentiation in private alleles and byssus phenotypes might suggest that the three wild populations have experienced different environmental selective pressures.This study provides insight for future genetic enhancement programs aimed at improving byssus attachment in M.coruscus.展开更多
Chinese hamster with Chinese characteristics is used in experiments,and it is of great value in the field of medical biology research.However,at present,there is no high-efficiency method for evaluating the genetic qu...Chinese hamster with Chinese characteristics is used in experiments,and it is of great value in the field of medical biology research.However,at present,there is no high-efficiency method for evaluating the genetic quality of Chinese hamsters.Here,we developed a novel Chinese hamster genetic quality detection system using single-nucleotide polymorphism(SNP)markers.To find SNP loci,we conducted whole genome sequencing on 24 Chinese hamsters.Then,we employed an SNP locus screening criterion that we set up previously and initially screened 214 SNP loci with wide genome distribution and high polymorphism level.Subsequently,we developed the SNP detection system using a multitarget region capture technique based on second-generation sequencing,and a 55 SNP panel for genetic evaluation of Chinese hamster populations was developed.PopGen.32.analysis results showed that the average effective allele number,Shannon index,observed heterozygosity,expected heterozygosity,average heterozygosity,polymorphism information,and other genetic parameters of Chinese hamster population A were higher than those in population B.Using scientific screening and optimization,we successfully developed a novel Chinese hamster SNP genetic detection system that can efficiently and accurately analyze the genetic quality of the Chinese hamster population.展开更多
To address the shortcomings of traditional Genetic Algorithm (GA) in multi-agent path planning, such as prolonged planning time, slow convergence, and solution instability, this paper proposes an Asynchronous Genetic ...To address the shortcomings of traditional Genetic Algorithm (GA) in multi-agent path planning, such as prolonged planning time, slow convergence, and solution instability, this paper proposes an Asynchronous Genetic Algorithm (AGA) to solve multi-agent path planning problems effectively. To enhance the real-time performance and computational efficiency of Multi-Agent Systems (MAS) in path planning, the AGA incorporates an Equal-Size Clustering Algorithm (ESCA) based on the K-means clustering method. The ESCA divides the primary task evenly into a series of subtasks, thereby reducing the gene length in the subsequent GA process. The algorithm then employs GA to solve each subtask sequentially. To evaluate the effectiveness of the proposed method, a simulation program was designed to perform path planning for 100 trajectories, and the results were compared with those of State-Of-The-Art (SOTA) methods. The simulation results demonstrate that, although the solutions provided by AGA are suboptimal, it exhibits significant advantages in terms of execution speed and solution stability compared to other algorithms.展开更多
Introduction Tibetan sheep,economically important animals on the Qinghai–Tibet Plateau,have diversified into numerous local breeds with unique characteristics through prolonged environmental adaptation and selective ...Introduction Tibetan sheep,economically important animals on the Qinghai–Tibet Plateau,have diversified into numerous local breeds with unique characteristics through prolonged environmental adaptation and selective breeding.However,most current research focuses on one or two breeds,and lacks a comprehensive representa-tion of the genetic diversity across multiple Tibetan sheep breeds.This study aims to fill this gap by investigating the genetic structure,diversity and high-altitude adaptation of 6 Tibetan sheep breeds using whole-genome rese-quencing data.Results Six Tibetan sheep breeds were investigated in this study,and whole-genome resequencing data were used to investigate their genetic structure and population diversity.The results showed that the 6 Tibetan sheep breeds exhibited distinct separation in the phylogenetic tree;however,the levels of differentiation among the breeds were minimal,with extensive gene flow observed.Population structure analysis broadly categorized the 6 breeds into 3 distinct ecological types:plateau-type,valley-type and Euler-type.Analysis of unique single-nucleotide polymor-phisms(SNPs)and selective sweeps between Argali and Tibetan sheep revealed that Tibetan sheep domestication was associated primarily with sensory and signal transduction,nutrient absorption and metabolism,and growth and reproductive characteristics.Finally,comprehensive analysis of selective sweep and transcriptome data sug-gested that Tibetan sheep breeds inhabiting different altitudes on the Qinghai–Tibet Plateau adapt by enhancing cardiopulmonary function,regulating body fluid balance through renal reabsorption,and modifying nutrient diges-tion and absorption pathways.Conclusion In this study,we investigated the genetic diversity and population structure of 6 Tibetan sheep breeds in Qinghai Province,China.Additionally,we analyzed the domestication traits and investigated the unique adapta-tion mechanisms residing varying altitudes in the plateau region of Tibetan sheep.This study provides valuable insights into the evolutionary processes of Tibetan sheep in extreme environments.These findings will also contribute to the preservation of genetic diversity and offer a foundation for Tibetan sheep diversity preservation and plateau animal environmental adaptation mechanisms.展开更多
The relationship between genetics and infectious diseases is important in shaping our understanding of disease susceptibility,progression,and treatment.Recent research shows the impact of genetic variations,such as he...The relationship between genetics and infectious diseases is important in shaping our understanding of disease susceptibility,progression,and treatment.Recent research shows the impact of genetic variations,such as heme-oxygenase promoter length,on diseases like malaria and sepsis,revealing both protective and inconclusive effects.Studies on vaccine responses highlight genetic markers like human leukocyte antigens,emphasizing the potential for personalized immunization strategies.The ongoing battle against drug-resistant tuberculosis(TB)illustrates the complexity of genomic variants in predicting resistance,highlighting the need for integrated diagnostic tools.Additionally,genome-wide association studies reveal antibiotic resistance mechanisms in bacterial genomes,while host genetic polymorphisms,such as those in solute carrier family 11 member 1 and vitamin D receptor,demonstrate their role in TB susceptibility.Advanced techniques like metagenomic next-generation sequencing promise detailed pathogen detection but face challenges in cost and accessibility.A case report involving a highly virulent Mycobacterium TB strain with the pks1 gene further highlights the need for genetic insights in understanding disease severity and developing targeted interventions.This evolving landscape emphasizes the role of genetics in infectious diseases,while also addressing the need for standardized studies and accessible technologies.展开更多
Understanding the evolutionary processes that influence the distribution of genetic diversity in natural populations is a key issue in evolutionary biology. Both species' distribution ranges and environmental grad...Understanding the evolutionary processes that influence the distribution of genetic diversity in natural populations is a key issue in evolutionary biology. Both species' distribution ranges and environmental gradients can influence this diversity through mechanisms such as gene flow, selection, and genetic drift. To explore how these forces interact, we assessed neutral and adaptive genetic variation in three widely distributed and two narrowly distributed bird species co-occurring along the Cauca River canyon in Antioquia, Colombia—a region of pronounced environmental heterogeneity. We sampled individuals across eight sites spanning the canyon's gradient and analyzed genetic diversity and structure using microsatellites and toll-like receptors (TLRs), a gene family involved in innate immunity. Widely distributed species consistently exhibited higher genetic diversity at both marker types compared to their narrowly distributed counterparts. Although we did not find a significant relationship between microsatellite heterozygosity and TLR heterozygosity, we evidenced a negative trend for widely distributed species and a positive trend for narrowly distributed species. This result suggests that there is a stronger effect of genetic drift in narrowly distributed species. Our results highlight the role of distribution range in maintaining genetic diversity and suggest that environmental gradients, by interacting with gene flow and selection, may influence patterns of adaptive variation.展开更多
文摘The intergeneric hybridization between Brassica napus L. cv. oro and Matthiola incana (L.) R. Br. was carried out to study the phytogenetic peculiarities of the hybrid plants. In order to improve the oil quality of rape seed, ovaries of B. napus pollinated with pollen of M. incana, were cut off and inoculated onto MS media supplemented with various plant hormones at the 7th day after pollination. Two mature embryos were obtained from 750 pollinated ovaries cultured in vitro. The percentage of seed set was 0.26%. The mature embryos were transferred onto the MS media supplemented with 2.0 mg/L 6-BA + 0.1 mg/L NAA, and a compound bud was produced later. The compound bud was then cut into a number of single buds, which were transferred onto fresh media. Twenty-two plantlets in vitro were developed from the above single buds. The hybrid plants (F-1) were basically intermediate between the two parents in many,characters with a few showing hybrid vigor. The fertility of hybrid plants (F-1) was poor. Cytological studies revealed that the hybrid plants (F-1) were mixoploid. in nature. The chromosome number of many somatic cells was 2n = 26, which was the sum of the chromosome number of the two parents. The chromosome number of other somatic cells was 2n = 38, similar to that of B. napus. The hybrid offspring (F-2) from the selfed hybrid plants (F-1) showed polymorphism. Among the hybrid offspring (F-2) some were nearly matroclinous and fertile, similar to B. napus. some others were intermediate between the two parents and less fertile, and a few were poorly developed and nearly infertile. From the hybrid offspring a few plants with improved seed-oil quality were obtained.
基金National Basic Research Program of China(5132004)
文摘To improve performances of multi-objective optimization algorithms, such as convergence and diversity, a hybridization- encouraged mechanism is proposed and realized in elitist nondominated sorting genetic algorithm （NSGA-Ⅱ）. This mechanism uses the normalized distance to evaluate the difference among genes in a population. Three possible modes of crossover operators--＂Max Distance＂, ＂Min-Max Distance＂, and ＂Neighboring-Max＂--are suggested and analyzed. The mode of ＂Neighboring-Max＂, which not only takes advantage of hybridization but also improves the distribution of the population near Pareto optimal front, is chosen and used in NSGA-Ⅱ on the basis of hybridization-encouraged mechanism （short for HEM-based NSGA-Ⅱ）. To prove the HEM-based algorithm, several problems are studied by using standard NSGA-Ⅱ and the presented method. Different evaluation criteria are also used to judge these algorithms in terms of distribution of solutions, convergence, diversity, and quality of solutions. The numerical results indicate that the application of hybridization-encouraged mechanism could effectively improve the performances of genetic algorithm. Finally, as an example in engineering practices, the presented method is used to design a longitudinal flight control system, which demonstrates the obtainability of a reasonable and correct Pareto front.
基金funded by Natural Science Foundation of China(31500551)the Fundamental Research Funds for the Central Non-profit Research Institute of Chinese Academy of Forestry(CAFYBB2016QB008)+1 种基金Zhejiang Science and Technology Major Program on Agricultural New Variety Breeding(2016C02056-8)the Fundamental Research Funds for the Central Non-profit Research Institute of Research Institute of Subtropical Forestry-Chinese Academy of Forestry(RISF2014001)
文摘To achieve germplasm innovation and study genetic variation of important traits of bamboo plants,we used Bambusa multiplex,B.chungii,and Dendrocalamus latiflorus as parent materials for distant and inbred hybridizations.Two hybrid populations and three inbred populations were obtained:two populations consisted of 57 hybrid progenies from B.multiplex 9 B.chungii,26 hybrid progenies from B.multiplex 9 D.latiflorus,and three inbred progenies were from B.multiplex,B.chungii,and D.latiflorus.Traits for growth,morphology,and fiber were examined from the five populations when plants were 3 years old.Two hybrid populations had significant growth advantages in terms of height,diameter at ground level and internodal length.In terms of variability in morphological traits,the two hybrid populations followed the same trend,namely,seven morphological traits showed phenotypes that were intermediate to those of their parents;three morphological traits showed strong maternal effects,and three other morphological traits showed strong paternal effects.Among the five populations,the two hybrid populations had high arithmetic average fiber length,lengthweighted average fiber length and mass-weighted average fiber length,moreover,extensive variations of these three traits were observed within these two hybrid populations.The establishment of distant hybrid populations from these three bamboo species increased the genetic diversity more than in the other species examined.This work provides excellent materials for breeding new varieties and lays the foundation for understanding the genetics of important traits by analyzing related functional genes.
基金Supported by The Science and Technology Fund of Henan Health Department, No. 2007-026
文摘AIM: To characterize cytogenetic alterations in esophageal squamous cell carcinoma (ESCC) and its metastasis. METHODS: A total of 37 cases of primary ESCC and 15 pairs of primary ESCC tumors and their matched metastatic lymph nodes cases were enrolled from Linzhou, the high incidence area for ESCC in Henan, northern China. The comparative genomic hybridization (CGH) was applied to determine the chromosomal aberrations on the DNA extracted from the frozen ESCC and metastatic lymph node samples from these patients. RESULTS: CGH showed chromosomal aberrations in all the cases. In 37 cases of primary ESCC, chromosomal profile of DNA copy number was characterized by frequently detected gains at 8q (29/37, 78%), 3q (24/37, 65%), 5p (19/37, 51%); and frequently detected losses at 3p (21/37, 57%), 8p and 9q (14/37, 38%). In 15 pairs of primary ESCC tumors and their matched metastatic lymph node cases, the majority of the chromosomal aberrations in both primary tumor and metastatic lymph node lesions were consistent with the primary ESCC cases, but new candidate regions of interest were also detected. The most significant finding is the gains of chromosome 6p with a minimum high-level amplification region at 6p12-6q12 in 7 metastatic lymph nodes butonly in 2 corresponding primary tumors (P = 0.05) and 20p with a minimum high-level amplification region at 20p12 in 11 metastatic lymph nodes but only in 5 corresponding primary tumors (P < 0.05). Another interesting finding is the loss of chromosome 10p and 10q in 8 and 7 metastatic lymph nodes but only in 2 corresponding primary tumors (P < 0.05). CONCLUSION: Using the CGH technique to detect chromosomal aberrations in both the primary tumor and its metastatic lymph nodes of ESCC, gains of 8q, 3q and 5p and loss of 3p, 8p, 9q and 13q were specifically implicated in ESCC in Linzhou population. Gains of 6p and 20p and loss of 10pq may contribute to the lymph node metastasis of ESCC. These findings suggest that the gains and losses of chromosomal regions may contain ESCC-related oncogenes and tumor suppressor genes and provide important theoretic information for identifying and cloning novel ESCC-related oncogenes and tumor suppressor genes.
基金This research was partially supported by the Trans-century Training Program Foundation for the Talents by the State Education Commission of China to Dr.Chen Jinfeng,by the National Natural Science Founda-tion of China(301 70644 and 30470120)by National Hi-Tech R&D Program(2002AA241251 and 2004 AA241120)by Tang's Cornell-China Scholar Program and by Pickle Seed Research Foundation of PPI.
文摘Studies on the reproduction and cytogenetic characterization of a primary amphidiploid Cucumis species C. hytivus Chen and Kirkbride (2n = 4x = 38) indicated that a more comprehensive cytogenetic analysis of this species and its first selfed progeny would increase its potential utility in cucumber improvement. With tendrils used as source materials for mitotic analysis, chromosome numbers in all selfed progenies were 2n = 38, confirming chromosomal stability in this synthetic amphidiploid species. Detailed meiotic processes were described by comparing the primary and the selfed amphidiploids. Meiotic abnormalities, such as chromosome lagging, unequal separation, chromosome multi-polarization and polyads were observed frequently in all amphidiploid plants except for the selfed no.8, in which meiosis was arrested prior to metaphase Ⅰ. Generally, the frequency of multivalents was higher and the configurations were more complex in the selfed progenies, demonstrating a more extensive genetic exchange between cucumber and C. hystrix Chakr. Genome separation between cucumber and C. hystrix was observed through prophase Ⅰ to anaphase Ⅰ in both generations of the amphidiploids. Consequently, in addition to n = 19, a new gamete with n = 7 was produced, which was confirmed by the chromosome counts 2n = 14 in the backcrossing progenies from cucumber × amphidiploid mating. Fertility varied among the selfed amphidiploid plants. The selfed plant no.1 was found to have an improved fertility (e.g., pollen staining ability 40.8% and 25.6 seeds per fruit) and then was used as source germplasm in further introgression and gene exchange experiments.
文摘The genomic structures of Oryza sativa （A genome） and O. meyeriana （G genome） were comparatively studied using bicolor genomic in situ hybridization （GISH）. GISH was clearly able to discriminate between the chromosomes of O. sativa and O. meyeriana in the interspecific F1 hybrids without blocking DNA, and co-hybridization was hardly detected. The average mitotic chromosome length of O. meyeriana was found to be 1.69 times that of O. sativa. A comparison of 4,6-diamidino-2-phenylindole staining showed that the chromosomes of O. meyeriana were more extensively labelled, suggesting that the G genome is amplified with more repetitive sequences than the A genome. In interphase nuclei, 9-12 chromocenters were normally detected and nearly all the chromocenters constituted the G genome-specific DNA. More and larger chromocenters formed by chromatin compaction corresponding to the G genome were detected in the hybrid compared with its parents. During pachytene of the F1 hybrid, most chromosomes of A and G did not synapse each other except for 1-2 chromosomes paired at the end of their arms. At meiotic metaphase I, three types of chromosomal associations, i.e.O, sativa-O, sativa （A-A）, O. sativa-O, meyeriana （A-G） and O. meyeriana-O, meyeriana （G-G）, were observed in the F1 hybrid. The A-G chromosome pairing configurations included bivalents and trivalents. The results provided a foundation toward studying genome organization and evolution of O. meyeriana.
基金supported by the National Natural Science Foundation of China (30971845)
文摘indica and japonica are the two most important subspecies of Asian cultivated rice. Identifying mechanisms responsible for population differentiation in these subspecies is important for indica-japonica hybridization breeding. In this study, subspecies and economic trait differentiation patterns were analyzed using morphological and molecular （InDel and Intron Length Polymorphism） data in F2 and F3 populations derived from indica-japonica hybridization. Populations were grown in Liaoning and Guangdong provinces, China, with F3 populations generated from F2 populations using bulk harvesting （BM） and single-seed descent methods （SSD）. Segregation distortion was detected in F3-BM populations, but not in F3- SSD or in F2 populations. Superior performance was observed with respect to economic traits in Liaoning compared with that in Guangdong and 1 000-grain weight （KW）, seed setting rate （SSR） and grain yield per plant （GYP） were significantly correlated with indica and japonica subspecies types. Analysis of molecular and morphological data demonstrated that the environment is the main factor giving rise to population differentiation in indica-japonica hybridization. In addition, we also found that KW, SSR and GYP are related to subspecies characteristics and kinship, which is possibly a significant factor resulting in economic trait differentiation and determining environmental adaptability. Our study has provided new insights into the process of population differentiation in these subspecies to inform indica-japonica hybridization breeding.
基金Supported by the National Natural Science Foundation of China,No.82460940Major Project of Gansu Province Joint Fund,No.23JRRA1519+2 种基金Key Science and Technology Project of Gansu Province,No.21ZD4FA009Natural Science Foundation of Gansu Province,No.24JRRA1040Gansu Province Famous Traditional Chinese Medicine Inheritance Studio Project。
文摘Congenital scoliosis(CS)is a prevalent spinal deformity with a multifaceted etiology that remains incompletely understood.Recent advances in genetic and epigenetic research have provided novel insights into CS pathogenesis.Herein,we review the current progress in genetics and epigenetics to examine genetic variants,susceptibility factors,and the epigenetic regulatory mechanisms implicated in CS.Through an analysis of diverse genetic markers,chromosomal abnormalities,and epigenetic modifications,the correlation between genetic predisposition and environmental influences in CS pathogenesis is elucidated.By integrating these genetic and epigenetic findings,this study aims to clarify the underlying etiology of CS to provide guidance on future clinical interventions and promote the development of personalized therapeutic strategies.
基金supported by the National Key Resarch and Development Program of China(Grant No.2023YFD1200802)the Base Bank of Lingnan Rice Germplasm Resources Project,China(Grant No.2024B1212060009).
文摘Polyploidization is a commonly employed strategy in crop breeding to augment genetic diversity,particularly leveraging the distinctive benefits of additional progressive heterosis or multi-generation heterosis unique to polyploidy.Despite genetic disparities between polyploids and diploids,challenges stem from reproductive anomalies,complicating genetic investigations in polyploid systems.Through nearly two decades of intensive research,our team has effectively generated a series of fertile tetraploid lines known as neo-tetraploid rice(NTR),facilitating comparative genetic studies between diploid and tetraploid rice.In this study,we identified diploid counterparts(H3d and H8d)for two NTR lines[Huaduo 3(H3)and Huaduo 8(H8)]and utilized them to create diploid and tetraploid fertile F_(2) populations to assess genotype segregation ratios,recombination rates,and their impact on QTL mapping via bulked segregant analysis combined with sequencing(BSA-seq).Additionally,we assessed yield heterosis in F_(1) and F_(2) generations of two tetraploid populations(H3×H8 and T449×H1),revealing evidence of multi-generation heterosis in polyploid rice.These findings provide valuable insights into the advantages and challenges of polyploid rice breeding.
基金Supported by The European Union-Next Generation EU,through the National Recovery and Resilience Plan of the Republic of Bulgaria,No.BG-RRP-2.004-0008。
文摘Inflammatory bowel disease(IBD)represents a significant disease burden marked by chronic inflammation and complications that adversely affect patients’quality of life.Effective diagnostic strategies involve clinical assessments,endoscopic evaluations,imaging studies,and biomarker testing,where early diagnosis is essential for effective management and prevention of long-term complications,highlighting the need for continual advancements in diagnostic methods.The intricate interplay between genetic factors and the outcomes of biological therapy is of critical importance.Unraveling the genetic determinants that influence responses and failures to biological therapy holds significant promise for optimizing treatment strategies for patients with IBD on biologics.Through an indepth examination of current literature,this review article synthesizes critical genetic markers associated with therapeutic efficacy and resistance in IBD.Understanding these genetic actors paves the way for personalized approaches,informing clinicians on predicting,tailoring,and enhancing the effectiveness of biological therapies for improved outcomes in patients with IBD.
文摘Fluorescence in situ hybridization (FISH) has become an important tool both for defining initial chromosomal abnormalities within a disease process, and for monitoring response to therapy as well as minimal residual disease. We report the results of interphase FISH (iFISH) analysis of 92 patients. We have used five different FISH probes to detect common cytogenetic rearrangements associated with hematological malignancies. A total of 83 patients were screened for BCR/ABL gene rearrangements. Displayed iFISH patterns of BCR/ABL gene rearrangements in 37.3% of patients (31/83) ranged between 10% to 98%. In addition, while 3 patients and one patient with AML showed t(15;17) (12.5%) and inv(16;16) (8.3%) respectively, t(8;21) was not found. Furthermore, secondary chromosomal aberrations (6.5% of all cases) were clearly non random in the present study. The diagnosis of BCR/ABL gene rearrangements are likely become an important tool for the monitoring of therapies in patients with CML. Atypical patterns also may have clinical prognostic implications. Further studies in larger groups of patients are needed in order to elucidate the role of AML1/ETO, PML/RARA, CBFB and p53, and to identify the specific chromosomal regions and interacting genes involved in this process.
文摘The mussel is one of the main cultivated species in the world.A significant challenge faced by suspension-cultured mussels is the high incidence of mussel fall-off from cultivation ropes,adversely impacting harvest yields,which have been documented at commercial mussel farms in the United Kingdom,the United States of America,Canada,Spain,New Zealand and China.Byssus is an important attachment structure for marine mussels,and weakness in byssal thread attachment is a major factor leading to mussel detachment from ropes.To investigate the relationship between genetic variability and byssal thread phenotypic characteristics in the hard-shelled mussel(Mytilus coruscus),we collected three wild populations of M.coruscus from different latitudes in the East China Sea,including the Shengsi(SS),Jiaojiang(JJ),and Fuding(FD)populations.The genetic diversity and structure of these populations were investigated using 10 microsatellite loci.The mean observed heterozygosity(Ho)in the SS population was 0.44,higher than the mean Ho values of the JJ(0.40)and FD(0.39)populations.The mean inbreeding coefficients(F_(is))in the SS population was 0.20,lower than the mean F_(is)values of the JJ(0.33)and FD populations(0.40).These results revealed that the SS population exhibited higher genetic diversity compared to the other two populations.The different numbers of private alleles(P_(a))in the three populations,ranging from 10 to 17,suggest that these populations have experienced selective pressures from various environments.Moreover,genetic differentiation was observed in the genetic distance between the SS population and the other two populations.We also examined the phenotypic characteristics of their byssal threads.There were significant differences in byssus attachment strength among the three populations,with the SS population located at the highest latitude secreting more byssal threads and exhibiting greater byssal breaking force and plaque adhesion strength,while the Fuding(FD)population located at the lowest latitude had the weakest byssal attachment.The observed differentiation in private alleles and byssus phenotypes might suggest that the three wild populations have experienced different environmental selective pressures.This study provides insight for future genetic enhancement programs aimed at improving byssus attachment in M.coruscus.
基金National Key Research and Development Program for Young scientists,Grant/Award Number:2021YFF0703200National Natural Foundation Joint Fund for Regional Innovation and Development,Grant/Award Number:U21A20194+1 种基金National Natural Science Foundation of China,Grant/Award Number:32170540National Key Research and Development Program,Grant/Award Number:2022YFF0711005。
文摘Chinese hamster with Chinese characteristics is used in experiments,and it is of great value in the field of medical biology research.However,at present,there is no high-efficiency method for evaluating the genetic quality of Chinese hamsters.Here,we developed a novel Chinese hamster genetic quality detection system using single-nucleotide polymorphism(SNP)markers.To find SNP loci,we conducted whole genome sequencing on 24 Chinese hamsters.Then,we employed an SNP locus screening criterion that we set up previously and initially screened 214 SNP loci with wide genome distribution and high polymorphism level.Subsequently,we developed the SNP detection system using a multitarget region capture technique based on second-generation sequencing,and a 55 SNP panel for genetic evaluation of Chinese hamster populations was developed.PopGen.32.analysis results showed that the average effective allele number,Shannon index,observed heterozygosity,expected heterozygosity,average heterozygosity,polymorphism information,and other genetic parameters of Chinese hamster population A were higher than those in population B.Using scientific screening and optimization,we successfully developed a novel Chinese hamster SNP genetic detection system that can efficiently and accurately analyze the genetic quality of the Chinese hamster population.
文摘To address the shortcomings of traditional Genetic Algorithm (GA) in multi-agent path planning, such as prolonged planning time, slow convergence, and solution instability, this paper proposes an Asynchronous Genetic Algorithm (AGA) to solve multi-agent path planning problems effectively. To enhance the real-time performance and computational efficiency of Multi-Agent Systems (MAS) in path planning, the AGA incorporates an Equal-Size Clustering Algorithm (ESCA) based on the K-means clustering method. The ESCA divides the primary task evenly into a series of subtasks, thereby reducing the gene length in the subsequent GA process. The algorithm then employs GA to solve each subtask sequentially. To evaluate the effectiveness of the proposed method, a simulation program was designed to perform path planning for 100 trajectories, and the results were compared with those of State-Of-The-Art (SOTA) methods. The simulation results demonstrate that, although the solutions provided by AGA are suboptimal, it exhibits significant advantages in terms of execution speed and solution stability compared to other algorithms.
基金supported by the Natural Science Foundation of Qinghai Province(No.2022-ZJ-901)the National Breeding Joint Research Project。
文摘Introduction Tibetan sheep,economically important animals on the Qinghai–Tibet Plateau,have diversified into numerous local breeds with unique characteristics through prolonged environmental adaptation and selective breeding.However,most current research focuses on one or two breeds,and lacks a comprehensive representa-tion of the genetic diversity across multiple Tibetan sheep breeds.This study aims to fill this gap by investigating the genetic structure,diversity and high-altitude adaptation of 6 Tibetan sheep breeds using whole-genome rese-quencing data.Results Six Tibetan sheep breeds were investigated in this study,and whole-genome resequencing data were used to investigate their genetic structure and population diversity.The results showed that the 6 Tibetan sheep breeds exhibited distinct separation in the phylogenetic tree;however,the levels of differentiation among the breeds were minimal,with extensive gene flow observed.Population structure analysis broadly categorized the 6 breeds into 3 distinct ecological types:plateau-type,valley-type and Euler-type.Analysis of unique single-nucleotide polymor-phisms(SNPs)and selective sweeps between Argali and Tibetan sheep revealed that Tibetan sheep domestication was associated primarily with sensory and signal transduction,nutrient absorption and metabolism,and growth and reproductive characteristics.Finally,comprehensive analysis of selective sweep and transcriptome data sug-gested that Tibetan sheep breeds inhabiting different altitudes on the Qinghai–Tibet Plateau adapt by enhancing cardiopulmonary function,regulating body fluid balance through renal reabsorption,and modifying nutrient diges-tion and absorption pathways.Conclusion In this study,we investigated the genetic diversity and population structure of 6 Tibetan sheep breeds in Qinghai Province,China.Additionally,we analyzed the domestication traits and investigated the unique adapta-tion mechanisms residing varying altitudes in the plateau region of Tibetan sheep.This study provides valuable insights into the evolutionary processes of Tibetan sheep in extreme environments.These findings will also contribute to the preservation of genetic diversity and offer a foundation for Tibetan sheep diversity preservation and plateau animal environmental adaptation mechanisms.
文摘The relationship between genetics and infectious diseases is important in shaping our understanding of disease susceptibility,progression,and treatment.Recent research shows the impact of genetic variations,such as heme-oxygenase promoter length,on diseases like malaria and sepsis,revealing both protective and inconclusive effects.Studies on vaccine responses highlight genetic markers like human leukocyte antigens,emphasizing the potential for personalized immunization strategies.The ongoing battle against drug-resistant tuberculosis(TB)illustrates the complexity of genomic variants in predicting resistance,highlighting the need for integrated diagnostic tools.Additionally,genome-wide association studies reveal antibiotic resistance mechanisms in bacterial genomes,while host genetic polymorphisms,such as those in solute carrier family 11 member 1 and vitamin D receptor,demonstrate their role in TB susceptibility.Advanced techniques like metagenomic next-generation sequencing promise detailed pathogen detection but face challenges in cost and accessibility.A case report involving a highly virulent Mycobacterium TB strain with the pks1 gene further highlights the need for genetic insights in understanding disease severity and developing targeted interventions.This evolving landscape emphasizes the role of genetics in infectious diseases,while also addressing the need for standardized studies and accessible technologies.
基金funded by the Empresas Públicas de Medellín and Universidad de Antioquia.
文摘Understanding the evolutionary processes that influence the distribution of genetic diversity in natural populations is a key issue in evolutionary biology. Both species' distribution ranges and environmental gradients can influence this diversity through mechanisms such as gene flow, selection, and genetic drift. To explore how these forces interact, we assessed neutral and adaptive genetic variation in three widely distributed and two narrowly distributed bird species co-occurring along the Cauca River canyon in Antioquia, Colombia—a region of pronounced environmental heterogeneity. We sampled individuals across eight sites spanning the canyon's gradient and analyzed genetic diversity and structure using microsatellites and toll-like receptors (TLRs), a gene family involved in innate immunity. Widely distributed species consistently exhibited higher genetic diversity at both marker types compared to their narrowly distributed counterparts. Although we did not find a significant relationship between microsatellite heterozygosity and TLR heterozygosity, we evidenced a negative trend for widely distributed species and a positive trend for narrowly distributed species. This result suggests that there is a stronger effect of genetic drift in narrowly distributed species. Our results highlight the role of distribution range in maintaining genetic diversity and suggest that environmental gradients, by interacting with gene flow and selection, may influence patterns of adaptive variation.
