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1.
Zhonghua Yi Xue Za Zhi ; 99(33): 2615-2618, 2019 Sep 03.
Artigo em Chinês | MEDLINE | ID: mdl-31510723

RESUMO

Objective: To explore the clinical features and genetic causes of autism spectrum disorder (ASD) patients with epilepsy. Methods: The clinical data of five patients with ASD and epilepsy admitted to Xuanwu Hospital between September 2017 and September 2018 were collected, including medical history, intelligence level, developmental level, physical examination, neuroimaging and electroencephalogram. High-throughput whole-genome sequencing was applied to five patients and their parents. Results: Of five patients, four were male and one was female. All five patients had mild mental retardation, and one patient had significant growth retardation and craniofacial deformity. The average epilepsy onset age was 6.3 years old (7 months to 16 years). The main epileptic type was tonic-clonic seizure with abnormal EEG results. All patients have a favorable response to anti-epileptic drugs. Whole-exome sequencing (WES) revealed copy number variation in all 5 patients. Among them, 3 cases were reported to be pathogenic, and 2 cases were not reported (chromosome 16p13.3 duplication and chromosome 21q22.3 deletion). Conclusions: The results of current study support that autism spectrum disorders with seizures is often associated with copy number variations, such as Williams-Beuren region duplication syndrome, chromosome 15q11.2 duplication syndrome and chromosome 15q11.2 deletion syndrome. We reported two novel copy number variations (chromosome 16p13.3 duplication and chromosome 21q22.3 deletion) in two autism spectrum disorder patients with epileptic seizures.


Assuntos
Transtorno do Espectro Autista , Epilepsia , Adolescente , Transtorno do Espectro Autista/complicações , Criança , Pré-Escolar , Aberrações Cromossômicas , Cromossomos Humanos , Variações do Número de Cópias de DNA , Epilepsia/complicações , Feminino , Humanos , Lactente , Masculino , Convulsões
2.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(9): 935-937, 2019 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-31515794

RESUMO

OBJECTIVE: To explore the genetic basis for a patient with autism. METHODS: High-throughput sequencing was carried out to detect copy number variations in the patient. RESULTS: DNA sequencing found that the patient has carried a 0.11 Mb deletion in distal 2p16.3 spanning from genomic position 50 820 001 to 50 922 000, which resulted removal of exon 6 and part of intron 7 of the NRXN1 gene. The same deletion was not found his parents and brother. CONCLUSION: Partial deletion of the NRXN1 gene may underlie the disease in this patient.


Assuntos
Transtorno Autístico/genética , Moléculas de Adesão Celular Neuronais/genética , Deleção de Genes , Proteínas do Tecido Nervoso/genética , Variações do Número de Cópias de DNA , Humanos , Masculino
3.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(8): 837-840, 2019 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-31400141

RESUMO

OBJECTIVE: To analyze the clinical and molecular genetic characteristics of patient with Kleefstra syndrome 1. METHODS: Clinical data, chromosomal karyotype and whole genome copy number variations (CNVs) of the patient were analyzed. RESULTS: The patient was found to have a karyotype of 45,XX,-9[4]/46,XX,r(9)(p24q34)[56]. Whole-genome CNVs detection revealed that she has carried a heterozygous deletion of approximately 670 kb at 9q34.3, which encompassed the entire EHMT1 gene. The region is strongly associated with Kleefstra syndrome (1/9q telomere deletion). In addition, the patient also had heterozygous deletion of 9pter, which may predispose to formation of ring chromosome 9. CONCLUSION: The child was diagnosed with Kleefstra syndrome type 1 in conjunct with ring chromosome 9.


Assuntos
Cromossomos Humanos Par 9/genética , Anormalidades Craniofaciais/genética , Cardiopatias Congênitas/genética , Deficiência Intelectual/genética , Cromossomos em Anel , Criança , Deleção Cromossômica , Variações do Número de Cópias de DNA , Feminino , Humanos
4.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(7): 708-711, 2019 Jul 10.
Artigo em Chinês | MEDLINE | ID: mdl-31302917

RESUMO

OBJECTIVE: To correlate genotype with clinical phenotype of a child featuring multiple congenital malformations. METHODS: Clinical examination of the patient was carried out. Chromosome microarray analysis (CMA) was employed to detect genomic copy number variations (CNVs), and quantitative PCR (qPCR) was used for verifying the result. RESULTS: The child had congenital heart disease (ventricular septal defect, atrial septal defect, pulmonary arterial hypertension, and tricuspid regurgitation), psychomotor retardation, agenesis of corpus callosum, hypospadias and scoliosis. CMA has detected a 1.8 Mb deletion at 7p22.3, a 1.8 Mb duplication at 7p22.3p22.2 and a 23.5 Mb duplication at 7q33q36.3 in the fetus, all of which were de novo in origin. CONCLUSION: CMA can precisely detect microdeletion/duplications and facilitate the genotype-phenotype correlation analysis.


Assuntos
Anormalidades Múltiplas/genética , Cromossomos Humanos Par 7/genética , Variações do Número de Cópias de DNA , Cardiopatias Congênitas/genética , Criança , Testes Genéticos , Humanos , Masculino , Fenótipo , Deleção de Sequência
5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(7): 727-730, 2019 Jul 10.
Artigo em Chinês | MEDLINE | ID: mdl-31302922

RESUMO

OBJECTIVE: To analyze the clinical and molecular genetics features of a family affected with Say-Barber-Biesecker-Young-Simpson syndrome (SBBYSS). METHODS: High-throughput sequencing was used to detect copy number variations (CNVs) and pathogenic variant within the whole exome of the affected child. RESULTS: No pathogenic CNV was found in the child, while exome sequencing identified a heterozygous c.3367_c.3370delAGAA (p.Arg1123Argfs*6) frameshifting variant in the exon 16 of the KAT6B gene. The same variant was not found in either parent. CONCLUSION: The c.3367_c.3370delAGAA (p.R1123Rfs*6) probably underlies the disease in the affected child. Above finding has facilitated genetic counseling and prenatal diagnosis for the family.


Assuntos
Blefarofimose/genética , Hipotireoidismo Congênito/genética , Variações do Número de Cópias de DNA , Cardiopatias Congênitas/genética , Histona Acetiltransferases/genética , Deficiência Intelectual/genética , Instabilidade Articular/genética , Criança , Facies , Feminino , Humanos , Mutação , Fenótipo , Gravidez
6.
Genome Biol ; 20(1): 134, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31287019

RESUMO

We present SMURF-seq, a protocol to efficiently sequence short DNA molecules on a long-read sequencer by randomly ligating them to form long molecules. Applying SMURF-seq using the Oxford Nanopore MinION yields up to 30 fragments per read, providing an average of 6.2 and up to 7.5 million mappable fragments per run, increasing information throughput for read-counting applications. We apply SMURF-seq on the MinION to generate copy number profiles. A comparison with profiles from Illumina sequencing reveals that SMURF-seq attains similar accuracy. More broadly, SMURF-seq expands the utility of long-read sequencers for read-counting applications.


Assuntos
Variações do Número de Cópias de DNA , Análise de Sequência de DNA/métodos , Linhagem Celular Tumoral , Feminino , Humanos
7.
Rev Assoc Med Bras (1992) ; 65(6): 786-790, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31340305

RESUMO

OBJECTIVE: This study was to assess the genetic association of copy number variations in two genes (PRKAB2 and PPM1K) located in two regions (tetralogy of Fallot and ventricular septal defect) in a Chinese Han population. METHODS: A total of 200 congenital heart disease patients (100 tetralogy of Fallot patients and 100 ventricular septal defect patients) and 100 congenital heart defect-free controls were recruited, and quantitative real-time PCR analysis was used to replicate the association of two copy number variations with congenital heart defects in a Chinese Han population. RESULTS: One deletion at PRKAB2 and one duplication at PPM1K were found in two of the tetralogy of Fallot patients, respectively; while all these regions were duplicated in both ventricular septal defect patients and in the 100 congenital heart defects-free controls. CONCLUSIONS: We replicated the copy number variations at the disease-candidate genes of PRKAB2 and PPM1K with tetralogy of Fallot in a Chinese Han population, and in patients with ventricular septal defect mutations in these two genes were not found. These results indicate the same molecular population genetics exist in these two genes with different ethnicity. This shows that these two genes are possibly specific pf tetralogy of Fallot candidates.


Assuntos
Proteínas Quinases Ativadas por AMP/genética , Variações do Número de Cópias de DNA , Comunicação Interventricular/genética , Proteína Fosfatase 2C/genética , Tetralogia de Fallot/genética , Estudos de Casos e Controles , Estudos de Associação Genética , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Valores de Referência
8.
Virchows Arch ; 475(3): 383-389, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31250201

RESUMO

Gastric hyperplastic polyps are common and generally regarded as benign lesions, whereas gastric adenocarcinomas infrequently occur from gastric hyperplastic polyps. Although gastric hyperplastic polyps have received a lot of attention because of their association with malignant transformation, it remains unclear whether gastric hyperplastic polyps are neoplastic lesions that have sporadic genetic changes similar to colorectal hyperplastic polyps. We performed genome-wide analyses of two gastric adenocarcinomas with hyperplastic polyp components. The interface between "adenocarcinoma" and "hyperplastic polyp" components was fairly sharp, and the adenocarcinoma components had copy number alterations and TP53 mutations, whereas the hyperplastic polyp components had only single nucleotide polymorphisms, which were also found in adenocarcinoma components. We did not detect any somatic changes in the hyperplastic polyp components, even in genome-wide analyses, which was in contrast to the adenocarcinoma components. However, due to the small number of cases examined herein, further genetic analyses of more cases are needed.


Assuntos
Pólipos Adenomatosos/patologia , Pólipos Intestinais/patologia , Neoplasias Gástricas/genética , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Transformação Celular Neoplásica/patologia , Hibridização Genômica Comparativa/métodos , Variações do Número de Cópias de DNA/genética , Feminino , Estudo de Associação Genômica Ampla/métodos , Humanos , Hiperplasia , Polimorfismo de Nucleotídeo Único/genética , Pólipos/patologia , Neoplasias Gástricas/patologia , Proteína Supressora de Tumor p53/genética
9.
Cytogenet Genome Res ; 158(2): 56-62, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31158835

RESUMO

SHOX resides in the short arm pseudoautosomal region (PAR1) of the sex chromosomes and escapes X inactivation. SHOX haploinsufficiency underlies idiopathic short stature (ISS) and Leri-Weill dyschondrosteosis (LWD). A substantial percentage of cases with SHOX haploinsufficiency arise from pseudoautosomal copy number variations (CNVs) involving putative enhancer regions of SHOX. Our previous study using peripheral blood samples showed that some CpG dinucleotides adjacent to SHOX exon 1 were hypomethylated in a healthy woman and methylated in a woman with gross X chromosomal rearrangements. However, it remains unknown whether submicroscopic pseudoautosomal CNVs cause aberrant DNA methylation of SHOX-flanking CpG islands. In this study, we examined the DNA methylation status of SHOX-flanking CpG islands in 50 healthy individuals and 10 ISS/LWD patients with pseudoautosomal CNVs. In silico analysis detected 3 CpG islands within the 20-kb region from the translation start site of SHOX. Pyrosequencing and bisulfite sequencing of genomic DNA samples revealed that these CpG islands were barely methylated in peripheral blood cells and cultured chondrocytes of healthy individuals, as well as in peripheral blood cells of ISS/LWD patients with pseudoautosomal CNVs. These results, in conjunction with our previous findings, indicate that the DNA methylation status of SHOX-flanking CpG islands can be affected by gross X-chromosomal abnormalities, but not by submicroscopic CNVs in PAR1. Such CNVs likely disturb SHOX expression through DNA methylation-independent mechanisms, which need to be determined in future studies.


Assuntos
Metilação de DNA , Doenças Genéticas Ligadas ao Cromossomo X/genética , Transtornos do Crescimento/genética , Osteocondrodisplasias/genética , Proteína de Homoeobox de Baixa Estatura/genética , Adolescente , Adulto , Estudos de Casos e Controles , Células Cultivadas , Criança , Pré-Escolar , Condrócitos , Ilhas de CpG , Variações do Número de Cópias de DNA , Feminino , Humanos , Análise de Sequência de DNA
10.
BMC Bioinformatics ; 20(1): 336, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31208319

RESUMO

BACKGROUND: Numerical chromosomal variation is a hallmark of populations of malignant cells. Identifying the factors that promote numerical chromosomal variation is important for understanding mechanisms of carcinogenesis. However, the ability to quantify and visualize differences in chromosome number between experimentally-defined groups (e.g. control vs treated) obtained from single-cell experiments is currently limited by the lack of user-friendly software. RESULTS: Aneuvis is a web application that allows users to determine whether numerical chromosomal variation exists between experimental treatment groups. The web interface allows users to upload molecular cytogenetic or processed single cell whole-genome sequencing data in a cell-by-chromosome matrix format and automatically generates visualizations and summary statistics that reflect the degree of numeric chromosomal variability. CONCLUSIONS: Aneuvis is the first user-friendly web application to help researchers identify the genetic and environmental perturbations that promote numerical chromosomal variation. Aneuvis is freely available as a web application at https://dpique.shinyapps.io/aneuvis/ and the source code for the application is available at https://github.com/dpique/aneuvis .


Assuntos
Cromossomos/genética , Internet , Análise de Célula Única , Software , Linhagem Celular , Variações do Número de Cópias de DNA/genética , Humanos , Interface Usuário-Computador , Sequenciamento Completo do Genoma
11.
Nat Commun ; 10(1): 2595, 2019 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197163

RESUMO

Plasmid acquisition is an important mechanism of rapid adaptation and niche expansion in prokaryotes. Positive selection for plasmid-coded functions is a major driver of plasmid evolution, while plasmids that do not confer a selective advantage are considered costly and expected to go extinct. Yet, plasmids are ubiquitous in nature, and their persistence remains an evolutionary paradox. Here, we demonstrate that non-mobile plasmids persist over evolutionary timescales without selection for the plasmid function. Evolving a minimal plasmid encoding for antibiotics resistance in Escherichia coli, we discover that plasmid stability emerges in the absence of antibiotics and that plasmid loss is determined by transcription-replication conflicts. We further find that environmental conditions modulate these conflicts and plasmid persistence. Silencing the transcription of the resistance gene results in stable plasmids that become fixed in the population. Evolution of plasmid stability under non-selective conditions provides an evolutionary explanation for the ubiquity of plasmids in nature.


Assuntos
Adaptação Biológica/genética , Resistência Microbiana a Medicamentos/genética , Escherichia coli/genética , Plasmídeos/genética , Antibacterianos/farmacologia , Variações do Número de Cópias de DNA/genética , Evolução Molecular Direcionada/métodos , Genoma Bacteriano/genética , Plasmídeos/efeitos dos fármacos , Temperatura Ambiente
12.
Pestic Biochem Physiol ; 157: 80-87, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153480

RESUMO

The European red mite Panonychus ulmi (Koch) is a major pest of apple trees worldwide and causes significant damage to apple orchards in Iran. Pyrethroid insecticides/acaricides, such as fenpropathrin and fenvalerate, are widely used to control P. ulmi, but their long-term use may lead to low efficacy. Earlier studies investigating pyrethroid resistance in closely related mites such as Tetranychus urticae revealed that pyrethroid resistance was associated with point mutations in the voltage-gated sodium channel gene (vgsc). The aim of this study was to investigate the biochemical and molecular mechanisms of fenpropathrin and fenvalerate resistance in Iranian populations of P. ulmi. Pyrethroid toxicity bioassays were carried out on different P. ulmi field populations. Marand (resistance ratio, RR = 149), Maraqeh (RR = 90) and Mianeh2 (RR = 71) populations exhibited high levels of resistance to fenpropathrin, compared to a susceptible field population (Shahin Dej). Resistance was also observed for fenvalerate with resistance ratio's ranging from 2- to 20-fold. Synergism experiments and enzyme activity assays predicted a minor role for classical detoxification enzymes. In contrast, two amino acid substitutions in the VGSC, L1024V and F1538I, that were previously shown to confer pyrethroid resistance, were detected in all three resistant P. ulmi populations and point towards target-site insensitivity as the most likely resistance mechanism. Furthermore, sequencing after cloning of vgsc fragments from single haploid males revealed the presence of multiple copies of vgsc in a highly resistant strain. The link between resistance mutations and vgsc copy number variation should be the subject of future study, as this might be used to develop molecular markers for monitoring pyrethroid resistance of P. ulmi in the field.


Assuntos
Mutação Puntual/genética , Piretrinas/farmacologia , Canais de Sódio Disparados por Voltagem/genética , Animais , Variações do Número de Cópias de DNA/genética , Duplicação Gênica/efeitos dos fármacos , Duplicação Gênica/genética , Resistência a Inseticidas/genética , Irã (Geográfico) , Ácaros , Canais de Sódio Disparados por Voltagem/metabolismo
14.
J Dairy Sci ; 102(8): 7226-7236, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31202648

RESUMO

The mammalian Y chromosome gene families in the ampliconic region are expressed predominantly or exclusively in the testis, and their copy number variations (CNV) are significantly associated with male reproductive traits, suggesting they have important roles in spermatogenesis and testicular development. ZNF280AY (zinc finger protein 280A, Y-linked) is a member of the zinc finger protein family and has been identified as a bovid-specific Y-chromosome gene. The current study applied a reliable quantitative real-time PCR method to estimate the CNV of ZNF280AY in 715 bulls across 21 cattle breeds and to further investigate the association of the CNV of ZNF280AY with bull reproductive traits and ZNF280AY mRNA expression levels in adult testis. The results revealed that the median copy number of ZNF280AY was 47, and the copy number varied from 11 to 154, showing significant CNV between and within the investigated cattle breeds. In addition, all 715 bulls were classified into Y1, Y2, and Y3 lineage groups based on a rapid genotyping method described previously. Pairwise comparisons indicated that bulls belonging to the Y1 lineage had a significantly lower median copy number (40) than bulls belonging to the Y2 (52) and Y3 lineages (57). Association analysis revealed that the CNV of ZNF280AY was correlated negatively with the percentage of normal sperm and sperm concentration in Holstein bulls, whereas no significant correlation was observed with ejaculation volume, total sperm count, sperm motility, postthaw motility (PTM), and scrotal circumference in Holstein and Simmental bulls. Furthermore, no correlation was observed between ZNF280AY copy number and ZNF280AY mRNA expression levels in the testis. The current study suggests that the CNV of the ZNF280AY gene family is associated with male reproductive traits and may serve as a valuable marker for early bull fertility selection in Holstein breeding programs.


Assuntos
Bovinos/genética , Variações do Número de Cópias de DNA , Fertilidade/genética , Regulação da Expressão Gênica , Genes Ligados ao Cromossomo Y/genética , Reprodução/genética , Cromossomo Y/genética , Animais , Cruzamento , Bovinos/fisiologia , Marcadores Genéticos/genética , Genótipo , Masculino , Especificidade de Órgãos , Fenótipo , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Especificidade da Espécie , Contagem de Espermatozoides/veterinária , Motilidade Espermática/genética , Espermatogênese/genética , Testículo/fisiologia , Dedos de Zinco/genética
15.
Tijdschr Psychiatr ; 61(6): 421-425, 2019.
Artigo em Holandês | MEDLINE | ID: mdl-31243752

RESUMO

Genetic factors play an important role in the development of psychotic disorders. With increasing evidence, several rare copy number variants (cnvs) have been identified as risk factors. We describe a patient who had two psychotic episodes during his adolescence. In this patient, a 16p11.2 duplication was detected. This duplication is a recurrent cnv associated with various somatic and psychiatric phenotypes including psychosis and schizophrenia. The potential clinical relevance of this finding is discussed.


Assuntos
Transtornos Psicóticos/genética , Adolescente , Cromossomos Humanos Par 16 , Variações do Número de Cópias de DNA , Predisposição Genética para Doença , Humanos , Masculino , Fenótipo , Transtornos Psicóticos/diagnóstico , Adulto Jovem
16.
Surg Clin North Am ; 99(3): 403-418, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31047032

RESUMO

Esophageal cancer and gastric cancer are leading causes of cancer-related mortality worldwide. In this article, the authors discuss the molecular biology of esophageal and gastric cancer with a focus on esophageal adenocarcinoma. They review data from The Cancer Genome Atlas project and advances in the molecular stratification and classification of esophageal carcinoma and gastric cancer. They also summarize advances in microRNA, molecular staging, gene expression profiling, tumor microenvironment, and detection of circulating tumor DNA. Finally, the authors summarize some of the implications of understanding the molecular basis of esophageal cancer and future directions in the management of esophageal cancer.


Assuntos
Adenocarcinoma/genética , Neoplasias Esofágicas/genética , Neoplasias Gástricas/genética , Adenocarcinoma/epidemiologia , Esôfago de Barrett/epidemiologia , Esôfago de Barrett/genética , Variações do Número de Cópias de DNA/genética , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Neoplasias Esofágicas/epidemiologia , Previsões , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Humanos , Metástase Linfática , MicroRNAs , Mutação/genética , Estadiamento de Neoplasias , Fatores de Risco , Neoplasias Gástricas/epidemiologia , Microambiente Tumoral
17.
Gene ; 706: 162-171, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31085274

RESUMO

In clinical genetics, the need to discriminate between benign and pathogenic variants identified in patients with neurodevelopmental disorders is an absolute necessity. Copy number variants (CNVs) of small size can enable the identification of genes that are critical for neurologic development. However, assigning a definite association with a specific disorder is a difficult task. Among 328 trios analyzed over seven years of activity in a single laboratory, we identified 19 unrelated patients (5.8%) who carried a small (<500 kb) de novo CNV. Four patients had an additional independent de novo CNV. Nine had a variant that could be assigned as definitely pathogenic, whereas the remaining CNVs were considered as variants of unknown significance (VUS). We report clinical and molecular findings of patients harboring VUS. We reviewed the medical literature available for genes impacted by CNVs, obtained the probability of truncating loss-of-function intolerance, and compared overlapping CNVs reported in databases. The classification of small non-recurrent CNVs remains difficult but, among our findings, we provide support for a role of SND1 in the susceptibility of autism, describe a new case of the rare 17p13.1 microduplication syndrome, and report an X-linked duplication involving KIF4A and DLG3 as a likely cause of epilepsy.


Assuntos
Variações do Número de Cópias de DNA/genética , Transtornos do Neurodesenvolvimento/genética , Adulto , Transtorno Autístico/genética , Criança , Pré-Escolar , Epilepsia/genética , Feminino , Humanos , Lactente , Deficiência Intelectual/genética , Cinesina/genética , Masculino , Proteínas Nucleares/genética , Proteínas Nucleares/fisiologia , Fatores de Transcrição/genética
18.
Nat Commun ; 10(1): 2354, 2019 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-31142748

RESUMO

In allopolyploids, correct chromosome segregation requires suppression of non-homologous crossovers while levels of homologous crossovers are ensured. To date, no mechanism able to specifically inhibit non-homologous crossovers has been described in allopolyploids other than in bread wheat. Here, we show that reducing the number of functional copies of MSH4, an essential gene for the main crossover pathway, prevents non-homologous crossovers in allotetraploid Brassica napus. We show that non-homologous crossovers originate almost exclusively from the MSH4-dependent recombination pathway and that their numbers decrease when MSH4 returns to single copy in B. napus; by contrast, homologous crossovers remain unaffected by MSH4 duplicate loss. We also demonstrate that MSH4 systematically returns to single copy following numerous independent polyploidy events, a pattern that is probably not by chance. These results suggest that stabilization of allopolyploid meiosis can be enhanced by loss of a key meiotic recombination gene.


Assuntos
Brassica napus/genética , Segregação de Cromossomos/genética , Troca Genética/genética , Meiose/genética , Proteínas MutS/genética , Poliploidia , Cromossomos de Plantas/metabolismo , Variações do Número de Cópias de DNA , Recombinação Homóloga
19.
Anim Sci J ; 90(7): 849-856, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31067600

RESUMO

This study evaluated the effects of cryopreservation by slow freezing on the mitochondrial function, DNA integrity, and developmental ability of bovine embryos and examined whether resveratrol treatment of the frozen-thawed blastocysts improved embryonic viability. In vitro produced bovine embryos were subjected to slow freezing. After thawing, the ATP content and mitochondrial DNA integrity (mtDNA), determined by real-time PCR targeting short and long mitochondrial sequences, was found to be lower in frozen-thawed embryos than in fresh embryos, and mtDNA copy number was significantly reduced during the 24-hr incubation post warming. Furthermore, immunostaining against double-strand DNA revealed DNA damage in frozen-thawed embryos. When frozen-thawed embryos were incubated in the medium containing 0.5 µM resveratrol, SIRT1 expression, and survival rate of the embryos significantly improved compared with the vehicle-treated embryos. In addition, cell-free mtDNA content in medium was higher in case of resveratrol-treated embryos than of vehicle-treated embryos. In conclusion, slow freezing affects mitochondrial integrity and function in the blastocysts. In the frozen-thawed embryos, mitochondria were removed during post-thawing incubation and resveratrol enhanced the process, resulting in improved survivability of the embryos.


Assuntos
Blastocisto/fisiologia , Criopreservação/métodos , Desenvolvimento Embrionário/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Resveratrol/farmacologia , Preservação de Tecido/métodos , Trifosfato de Adenosina/metabolismo , Animais , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Variações do Número de Cópias de DNA/efeitos dos fármacos , Dano ao DNA , DNA Mitocondrial/metabolismo , Feminino , Mitocôndrias/genética
20.
Anim Reprod Sci ; 205: 78-87, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31036307

RESUMO

Mitochondria function as an energy transfer organelle for cell metabolism with the energy being used for processes such as reproduction. To investigate whether mutations and copy number variations in mitochondrial genes are related to the reproductive capacity of the Asian yellow pond turtle, Mauremys mutica, there was exploration of the distribution frequency of 129 Single Nucleotide Polymorphism loci of six mitochondrial genes, ND1, ND2, COX2, ND4, Cytb andD-loop, of turtles from a relatively greater and lesser fecundity group by direct sequencing. The validation results for five candidate SNP loci in 83 female turtles indicated that only three SNP loci (C119T, A320G and A417C) in ND1 were positively correlated with reproductive capacity in M. mutica (P < 0.05). In addition, by constructing linear regression equations of the copy numbers of ND1, ND4, Cytb, D-loop, COX3, and ATP6 (log10 transformed) genes and the mean offspring number of different female turtles during a 4-year period, the copy numbers of ND4 and ATP6 (log10 transformed) genes were positively correlated (P < 0.05) with the fecundity of female turtles. Results from the present study may provide useful genetic markers for breeding M. mutica with greater reproductive capacity.


Assuntos
Variações do Número de Cópias de DNA , DNA Mitocondrial/genética , Polimorfismo de Nucleotídeo Único , Reprodução/genética , Tartarugas/genética , Animais , Feminino , Masculino , Reprodução/fisiologia , Tartarugas/fisiologia
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