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2.
BMC Plant Biol ; 23(1): 530, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37907872

RESUMEN

BACKGROUND: Latania scale (Hemiberlesia lataniae Signoret) is an armoured scale insect known to cause damage to kiwifruit plants and fruit, which ultimately reduces crop values and creates post-harvest export and quarantine issues. Resistance to H. lataniae does exist in some commercial cultivars of kiwifruit. However, some of the commercial cultivars bred in New Zealand have not inherited alleles for resistance to H. lataniae carried by their parents. To elucidate the architecture of resistance in the parents and develop molecular markers to assist breeding, these experiments analysed the inheritance of resistance to H. lataniae from families related to commercial cultivars. RESULTS: The first experiment identified a 15.97 Mb genomic region of interest for resistance to H. lataniae in rtGBS data of 3.23 to 19.20 Mb on chromosome 10. A larger population was then QTL mapped, which confirmed the region of interest as the sole locus contributing to H. lataniae resistance. inDel markers mapping the region of low recombination under the QTL peak further narrowed the region associated with H. lataniae resistance to a 5.73 Mb region. CONCLUSIONS: The kiwifruit populations and genomic methods used in this study identify the same non-recombinant region of chromosome 10 which confers resistance of A. chinensis var. chinensis to H. lataniae. The markers developed to target the H. lataniae resistance loci will reduce the amount of costly and time-consuming phenotyping required for breeding H. lataniae scale resistance into new kiwifruit cultivars.


Asunto(s)
Actinidia , Frutas , Humanos , Frutas/genética , Fitomejoramiento , Genómica , Genoma de Planta , Nueva Zelanda , Actinidia/genética
4.
Evol Appl ; 15(4): 591-602, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35505891

RESUMEN

Aquaculture is the fastest-growing food production sector worldwide, yet industry has been slow to implement genomic techniques as routine tools. Applying genomics to new breeding programmes can provide important information about pedigree structure and genetic diversity; key parameters for a successful long-term breeding programme. It can also provide insights on potential gains for commercially important, yet complex, quantitative traits such as growth rate. Here we investigated a population of 1100 captive-bred F1 silver trevally (Pseudocaranx georgianus), a promising new species for New Zealand aquaculture. We used whole-genome information, coupled with image-based phenotypic data collected over two years, to build the pedigree of the population, assess its genetic diversity, describe growth patterns of ten growth traits and estimate their genetic parameters. Successful parentage assignment of 664 F1 individuals showed that the pedigree consisted of a complex mixture of full- and half-sib individuals, with skewed reproductive success among parents, especially in females. Growth patterns showed seasonal fluctuations (average increase across all traits of 27.3% in summer and only 7% in winter) and strong inter-family differences. Heritability values for growth traits ranged from 0.27 to 0.76. Genetic and phenotypic correlations between traits were high and positive, ranging from 0.57 to 0.94 and 0.50 to 1.00 respectively. The implications of these findings are threefold: first, the best on-growing conditions are in warmer months, where highest growth peaks can be achieved; second, size- and family-based selection can be used as early selection criterion if pedigree structure and inbreeding risks are closely monitored; third, selection for body length results in concomitant increases in height and weight, traits of paramount importance for aquaculture. It is concluded that there is substantial potential for genetic improvement of economically important traits, suggesting that silver trevally is a promising species for selective breeding for enhanced growth.

5.
Evol Appl ; 15(2): 237-248, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35233245

RESUMEN

Ectotherm species, such as marine fishes, depend on environmental temperature to regulate their vital functions. In finfish aquaculture production, being able to predict physiological responses in growth and other economic traits to temperature is crucial to address challenges inherent in the selection of grow-out locations. This will become an even more significant issue under the various predicted future climate change scenarios. In this study, we used the marine teleost silver trevally (Pseudocaranx georgianus), a species currently being explored as a candidate for aquaculture in New Zealand, as a model to study plasticity in gene expression patterns and growth in response to different temperatures. Using a captive study population, temperature conditions were experimentally manipulated for 1 month to mimic seasonal extremes. Phenotypic differences in growth were measured in 400 individuals, and gene expression patterns of pituitary gland and liver were determined in a subset of 100 individuals. Results showed that growth increased 50% in the warmer compared with the colder condition, suggesting that temperature has a large impact on metabolic activities associated with growth. A total of 265,116,678 single-end RNA sequence reads were aligned to the trevally genome, and 28,416 transcript models were developed (27,887 of these had GenBank accessions, and 17,980 unique gene symbols). Further filtering reduced this set to 8597 gene models. 39 and 238 differentially expressed genes (DEGs) were found in the pituitary gland and the liver, respectively (|log2FC| > 0.26, p-value < 0.05). Of these, 6 DEGs showed a common expression pattern between both tissues, all involved in housekeeping functions. Temperature-modulated growth responses were linked to major pathways affecting metabolism, cell regulation and signalling, previously shown to be important for temperature tolerance in other fish species. An interesting finding of this study was that genes linked to the reproductive system were up-regulated in both tissues in the high treatment, indicating the onset of sexual maturation. Few studies have investigated the thermal plasticity of the gene expression in the main organs of the somatotropic axis simultaneously. Our findings indicate that trevally exhibit substantial growth differences and predictable plastic regulatory responses to different temperature conditions. We identified a set of genes that provide a list of candidates for further investigations for selective breeding objectives and how populations may adapt to increasing temperatures.

6.
Insects ; 13(3)2022 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-35323562

RESUMEN

The light brown apple moth, Epiphyas postvittana is an invasive, polyphagous pest of horticultural systems around the world. With origins in Australia, the pest has subsequently spread to New Zealand, Hawaii, California and Europe, where it has been found on over 500 plants, including many horticultural crops. We have produced a genomic resource, to understand the biological basis of the polyphagous and invasive nature of this and other lepidopteran pests. The assembled genome sequence encompassed 598 Mb and has an N50 of 301.17 kb, with a BUSCO completion rate of 97.9%. Epiphyas postvittana has 34% of its assembled genome represented as repetitive sequences, with the majority of the known elements made up of longer DNA transposable elements (14.07 Mb) and retrotransposons (LINE 17.83 Mb). Of the 31,389 predicted genes, 28,714 (91.5%) were assigned to 11,438 orthogroups across the Lepidoptera, of which 945 were specific to E. postvittana. Twenty gene families showed significant expansions in E. postvittana, including some likely to have a role in its pest status, such as cytochrome p450s, glutathione-S-transferases and UDP-glucuronosyltransferases. Finally, using a RAD-tag approach, we investigated the population genomics of this pest, looking at its likely patterns of invasion.

7.
Obes Surg ; 32(4): 1034-1048, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35132569

RESUMEN

BACKGROUND: Despite the low rates of complications of bariatric surgery, gastrointestinal leaks are major adverse events that increase post-operative morbidity and mortality. Endoscopic treatment using self-expanding stents has been used in the therapeutic management of these complications with preliminary good results. METHODS: We performed a systematic review and meta-analysis of self-expanding stents placement for the management of gastrointestinal leaks after obesity surgery. Overall proportion of successful leak closure, stent migration, and reoperation were analysed as primary outcomes. Secondary outcomes were patients' clinical characteristics, duration and type of stent, other stent complications, and mortality. RESULTS: A meta-analysis of studies reporting stents was performed, including 488 patients. The overall proportion of successful leak closure was 85.89% (95% CI, 82.52-89.25%), median interval between stent placement and its removal of 44 days. Stent migration was noted in 18.65% (95% CI, 14.32-22.98%) and the overall proportion of re-operation was in 13.54% (95% CI, 9.94-17.14%). The agreement between reviewers for the collected data gave a Cohen's κ value of 1.0. No deaths were caused directly by complications with the stent placement. CONCLUSIONS: Endoscopic placement of self-expanding stents can be used, in selected patients, for the management of leaks after bariatric surgery with a high rate of effectiveness and low mortality rates. Nevertheless, reducing stent migration and re-operation rates represents an important challenge for future studies.


Asunto(s)
Cirugía Bariátrica , Obesidad Mórbida , Fuga Anastomótica/etiología , Fuga Anastomótica/cirugía , Cirugía Bariátrica/efectos adversos , Cirugía Bariátrica/métodos , Humanos , Obesidad Mórbida/cirugía , Estudios Retrospectivos , Stents/efectos adversos , Resultado del Tratamiento
8.
Mol Ecol Resour ; 22(1): 345-360, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34260155

RESUMEN

Bilberry (Vaccinium myrtillus L.) belongs to the Vaccinium genus, which includes blueberries (Vaccinium spp.) and cranberry (V. macrocarpon). Unlike its cultivated relatives, bilberry remains largely undomesticated, with berry harvesting almost entirely from the wild. As such, it represents an ideal target for genomic analysis, providing comparisons with the domesticated Vaccinium species. Bilberry is prized for its taste and health properties and has provided essential nutrition for Northern European indigenous populations. It contains high concentrations of phytonutrients, with perhaps the most important being the purple colored anthocyanins, found in both skin and flesh. Here, we present the first bilberry genome assembly, comprising 12 pseudochromosomes assembled using Oxford Nanopore (ONT) and Hi-C Technologies. The pseudochromosomes represent 96.6% complete BUSCO genes with an assessed LAI score of 16.3, showing a high conservation of synteny against the blueberry genome. Kmer analysis showed an unusual third peak, indicating the sequenced samples may have been from two individuals. The alternate alleles were purged so that the final assembly represents only one haplotype. A total of 36,404 genes were annotated after nearly 48% of the assembly was masked to remove repeats. To illustrate the genome quality, we describe the complex MYBA locus, and identify the key regulating MYB genes that determine anthocyanin production. The new bilberry genome builds on the genomic resources and knowledge of Vaccinium species, to help understand the genetics underpinning some of the quality attributes that breeding programs aspire to improve. The high conservation of synteny between bilberry and blueberry genomes means that comparative genome mapping can be applied to transfer knowledge about marker-trait association between these two species, as the loci involved in key characters are orthologous.


Asunto(s)
Vaccinium myrtillus , Antocianinas , Cromosomas , Frutas/genética , Genómica , Humanos
9.
Evol Appl ; 14(12): 2848-2863, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34950233

RESUMEN

The assessment of the genetic structuring of biodiversity is crucial for management and conservation. This is particularly critical for widely distributed and highly mobile deep-water teleosts, such as hoki (Macruronus novaezelandiae). This species is significant to Maori people and supports the largest commercial fishery in New Zealand, but uncertainty about its stock structure presents a challenge for management. Here, we apply a comprehensive genomic analysis to shed light on the demographic structure of this species by (1) assembling the genome, (2) generating a catalogue of genome-wide SNPs to infer the stock structure and (3) identifying regions of the genome under selection. The final genome assembly used short and long reads and is near complete, representing 93.8% of BUSCO genes, and consisting of 566 contigs totalling 501 Mb. Whole-genome re-sequencing of 510 hoki sampled from 14 locations around New Zealand and Australia, at a read depth greater than 10×, produced 227,490 filtered SNPs. Analyses of these SNPs were able to resolve the stock structure of hoki into two genetically and geographically distinct clusters, one including the Australian and the other one all New Zealand locations, indicating genetic exchange between these regions is limited. Location differences within New Zealand samples were much more subtle (global F ST  = 0.0006), and while small and significant differences could be detected, they did not conclusively identify additional substructures. Ten putative adaptive SNPs were detected within the New Zealand samples, but these also did not geographically partition the dataset further. Contemporary and historical N e estimation suggest the current New Zealand population of hoki is large yet declining. Overall, our study provides the first genomic resources for hoki and provides detailed insights into the fine-scale population genetic structure to inform the management of this species.

10.
Hortic Res ; 8(1): 233, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34719690

RESUMEN

The Rosaceae family has striking phenotypic diversity and high syntenic conservation. Gillenia trifoliata is sister species to the Maleae tribe of apple and ~1000 other species. Gillenia has many putative ancestral features, such as herb/sub-shrub habit, dry fruit-bearing and nine base chromosomes. This coalescence of ancestral characters in a phylogenetically important species, positions Gillenia as a 'rosetta stone' for translational science within Rosaceae. We present genomic and phenological resources to facilitate the use of Gillenia for this purpose. The Gillenia genome is the first fully annotated chromosome-level assembly with an ancestral genome complement (x = 9), and with it we developed an improved model of the Rosaceae ancestral genome. MADS and NAC gene family analyses revealed genome dynamics correlated with growth and reproduction and we demonstrate how Gillenia can be a negative control for studying fleshy fruit development in Rosaceae.

11.
BMC Genomics ; 22(1): 785, 2021 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-34727894

RESUMEN

BACKGROUND: The genetic control of sex determination in teleost species is poorly understood. This is partly because of the diversity of mechanisms that determine sex in this large group of vertebrates, including constitutive genes linked to sex chromosomes, polygenic constitutive mechanisms, environmental factors, hermaphroditism, and unisexuality. Here we use a de novo genome assembly of New Zealand silver trevally (Pseudocaranx georgianus) together with sex-specific whole genome sequencing data to detect sexually divergent genomic regions, identify candidate genes and develop molecular makers. RESULTS: The de novo assembly of an unsexed trevally (Trevally_v1) resulted in a final assembly of 579.4 Mb in length, with a N50 of 25.2 Mb. Of the assembled scaffolds, 24 were of chromosome scale, ranging from 11 to 31 Mb in length. A total of 28,416 genes were annotated after 12.8 % of the assembly was masked with repetitive elements. Whole genome re-sequencing of 13 wild sexed trevally (seven males and six females) identified two sexually divergent regions located on two scaffolds, including a 6 kb region at the proximal end of chromosome 21. Blast analyses revealed similarity between one region and the aromatase genes cyp19 (a1a/b) (E-value < 1.00E-25, identity > 78.8 %). Males contained higher numbers of heterozygous variants in both regions, while females showed regions of very low read-depth, indicative of male-specificity of this genomic region. Molecular markers were developed and subsequently tested on 96 histologically-sexed fish (42 males and 54 females). Three markers amplified in absolute correspondence with sex (positive in males, negative in females). CONCLUSIONS: The higher number of heterozygous variants in males combined with the absence of these regions in females support a XY sex-determination model, indicating that the trevally_v1 genome assembly was developed from a male specimen. This sex system contrasts with the ZW sex-determination model documented in closely related carangid species. Our results indicate a sex-determining function of a cyp19a1a-like gene, suggesting the molecular pathway of sex determination is somewhat conserved in this family. The genomic resources developed here will facilitate future comparative work, and enable improved insights into the varied sex determination pathways in teleosts. The sex marker developed in this study will be a valuable resource for aquaculture selective breeding programmes, and for determining sex ratios in wild populations.


Asunto(s)
Peces , Genoma , Animales , Femenino , Peces/genética , Genómica , Masculino , Nueva Zelanda , Cromosomas Sexuales/genética
12.
BMC Plant Biol ; 21(1): 334, 2021 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-34261431

RESUMEN

BACKGROUND: The skin (exocarp) of fleshy fruit is hugely diverse across species. Most fruit types have a live epidermal skin covered by a layer of cuticle made up of cutin while a few create an outermost layer of dead cells (peridermal layer). RESULTS: In this study we undertook crosses between epidermal and peridermal skinned kiwifruit, and showed that epidermal skin is a semi-dominant trait. Furthermore, backcrossing these epidermal skinned hybrids to a peridermal skinned fruit created a diverse range of phenotypes ranging from epidermal skinned fruit, through fruit with varying degrees of patches of periderm (russeting), to fruit with a complete periderm. Quantitative trait locus (QTL) analysis of this population suggested that periderm formation was associated with four loci. These QTLs were aligned either to ones associated with russet formation on chromosome 19 and 24, or cuticle integrity and coverage located on chromosomes 3, 11 and 24. CONCLUSION: From the segregation of skin type and QTL analysis, it appears that skin development in kiwifruit is controlled by two competing factors, cuticle strength and propensity to russet. A strong cuticle will inhibit russeting while a strong propensity to russet can create a continuous dead skinned periderm.


Asunto(s)
Actinidia/genética , Frutas/genética , Genes de Plantas , Sitios Genéticos , Desarrollo de la Planta/genética , Actinidia/crecimiento & desarrollo , Cruzamientos Genéticos , Frutas/crecimiento & desarrollo , Genotipo , Fenotipo , Sitios de Carácter Cuantitativo
13.
Mol Ecol Resour ; 21(6): 2125-2144, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33955186

RESUMEN

We used long read sequencing data generated from Knightia excelsa, a nectar-producing Proteaceae tree endemic to Aotearoa (New Zealand), to explore how sequencing data type, volume and workflows can impact final assembly accuracy and chromosome reconstruction. Establishing a high-quality genome for this species has specific cultural importance to Maori and commercial importance to honey producers in Aotearoa. Assemblies were produced by five long read assemblers using data subsampled based on read lengths, two polishing strategies and two Hi-C mapping methods. Our results from subsampling the data by read length showed that each assembler tested performed differently depending on the coverage and the read length of the data. Subsampling highlighted that input data with longer read lengths but perhaps lower coverage constructed more contiguous, kmers and gene-complete assemblies than short read length input data with higher coverage. The final genome assembly was constructed into 14 pseudochromosomes using an initial flye long read assembly, a racon/medaka/pilon combined polishing strategy, salsa2 and allhic scaffolding, juicebox curation, and Macadamia linkage map validation. We highlighted the importance of developing assembly workflows based on the volume and read length of sequencing data and established a robust set of quality metrics for generating high-quality assemblies. Scaffolding analyses highlighted that problems found in the initial assemblies could not be resolved accurately by Hi-C data and that assembly scaffolding was more successful when the underlying contig assembly was of higher accuracy. These findings provide insight into how quality assessment tools can be implemented throughout genome assembly pipelines to inform the de novo reconstruction of a high-quality genome assembly for nonmodel organisms.


Asunto(s)
Genoma de Planta , Genómica , Proteaceae , Secuenciación de Nucleótidos de Alto Rendimiento , Nueva Zelanda , Proteaceae/genética , Análisis de Secuencia de ADN
14.
Am J Surg ; 222(2): 446-452, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33234235

RESUMEN

BACKGROUND: Although bullfighting festivals were traditionally attributed to the cultural idiosyncrasies of the Ibero-American people, they also exist world-wide. METHODS: A retrospective study was conducted, reviewing the medical records of patients treated on our service for bull horn injuries between January 1978 and December 2019. RESULTS: There were 572 admissions due to bull horn injuries. 54 of these patients had multiple injuries. The average annual admission was 13.6 patients. The most frequent injuries were located in the lower extremities, perineum, and abdomen. Forty-seven laparotomies were performed, revealing intra-abdominal visceral impairment on 39 occasions. The most frequently injured organs were the intestine and liver. The most frequent complications were skin devitalisation, infection and post-operative eventration. The recorded mortality was 0.87%. CONCLUSION: We wish to highlight the importance of injuries caused by bull horns worldwide. These are high-impact injuries with specific intrinsic characteristics that require regulated medical and surgical care.


Asunto(s)
Cuernos , Complicaciones Posoperatorias/epidemiología , Heridas Penetrantes/epidemiología , Heridas Penetrantes/patología , Animales , Bovinos , Hospitalización , Humanos , Estudios Retrospectivos , España , Factores de Tiempo , Heridas Penetrantes/cirugía
15.
Plant Methods ; 16: 121, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32884578

RESUMEN

BACKGROUND: Genomic methods for identifying causative variants for trait loci applicable to a wide range of germplasm are required for plant biologists and breeders to understand the genetic control of trait variation. RESULTS: We implemented Cas9-targeted sequencing for fine-mapping in apple, a method combining CRISPR-Cas9 targeted cleavage of a region of interest, followed by enrichment and long-read sequencing using the Oxford Nanopore Technology (ONT). We demonstrated the capability of this methodology to specifically cleave and enrich a plant genomic locus spanning 8 kb. The repeated mini-satellite motif located upstream of the Malus × domestica (apple) MYB10 transcription factor gene, causing red fruit colouration when present in a heterozygous state, was our exemplar to demonstrate the efficiency of this method: it contains a genomic region with a long structural variant normally ignored by short-read sequencing technologiesCleavage specificity of the guide RNAs was demonstrated using polymerase chain reaction products, before using them to specify cleavage of high molecular weight apple DNA. An enriched library was subsequently prepared and sequenced using an ONT MinION flow cell (R.9.4.1). Of the 7,056 ONT reads base-called using both Albacore2 (v2.3.4) and Guppy (v3.2.4), with a median length of 9.78 and 9.89 kb, respectively, 85.35 and 91.38%, aligned to the reference apple genome. Of the aligned reads, 2.98 and 3.04% were on-target with read depths of 180 × and 196 × for Albacore2 and Guppy, respectively, and only five genomic loci were off-target with read depth greater than 25 × , which demonstrated the efficiency of the enrichment method and specificity of the CRISPR-Cas9 cleavage. CONCLUSIONS: We demonstrated that this method can isolate and resolve single-nucleotide and structural variants at the haplotype level in plant genomic regions. The combination of CRISPR-Cas9 target enrichment and ONT sequencing provides a more efficient technology for fine-mapping loci than genome-walking approaches.

16.
Ecol Evol ; 10(16): 8643-8651, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32884647

RESUMEN

The more demanding requirements of DNA preservation for genomic research can be difficult to meet when field conditions limit the methodological approaches that can be used or cause samples to be stored in suboptimal conditions. Such limitations may increase rates of DNA degradation, potentially rendering samples unusable for applications such as genome-wide sequencing. Nonetheless, little is known about the impact of suboptimal sampling conditions. We evaluated the performance of two widely used preservation solutions (1. DESS: 20% DMSO, 0.25 M EDTA, NaCl saturated solution, and 2. Ethanol >99.5%) under a range of storage conditions over a three-month period (sampling at 1 day, 1 week, 2 weeks, 1 month, and 3 months) to provide practical guidelines for DNA preservation. DNA degradation was quantified as the reduction in average DNA fragment size over time (DNA fragmentation) because the size distribution of DNA segments plays a key role in generating genomic datasets. Tissues were collected from a marine teleost species, the Australasian snapper, Chrysophrys auratus. We found that the storage solution has a strong effect on DNA preservation. In DESS, DNA was only moderately degraded after three months of storage while DNA stored in ethanol showed high levels of DNA degradation already within 24 hr, making samples unsuitable for next-generation sequencing. Here, we conclude that DESS was the most promising solution when storing samples for genomic applications. We recognize that the best preservation protocol is highly dependent on the organism, tissue type, and study design. We highly recommend performing similar experiments before beginning a study. This study highlights the importance of testing sample preservation protocols and provides both practical and economical advice to improve DNA preservation when sampling for genome-wide applications.

17.
Hortic Res ; 7: 47, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32257233

RESUMEN

The allelic diversity of primitive germplasm of fruit crops provides a useful resource for introgressing novel genes to meet consumer preferences and environmental challenges. Pre-breeding facilitates the identification of novel genetic variation in the primitive germplasm and expedite its utilisation in cultivar breeding programmes. Several generations of pre-breeding could be required to minimise linkage drag from the donor parent and to maximise the genomic content of the recipient parent. In this study we investigated the potential of genomic selection (GS) as a tool for rapid background selection of parents for the successive generation. A diverse set of 274 accessions was genotyped using random-tag genotyping-by-sequencing, and phenotyped for eight fruit quality traits. The relationship between 'own phenotypes' of 274 accessions and their general combining ability (GCA) was also examined. Trait heritability influenced the strength of correspondence between own phenotype and the GCA. The average (across eight traits) accuracy of predicting own phenotype was 0.70, and the correlations between genomic-predicted own phenotype and GCA were similar to the observed correlations. Our results suggest that genome-assisted parental selection (GAPS) is a credible alternative to phenotypic parental selection, so could help reduce the generation interval to allow faster accumulation of favourable alleles from donor and recipient parents.

18.
Plants (Basel) ; 8(7)2019 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-31336644

RESUMEN

During analysis of kiwifruit derived from hybrids between the high vitamin C (ascorbic acid; AsA) species Actinidia eriantha and A. chinensis, we observed bimodal segregation of fruit AsA concentration suggesting major gene segregation. To test this hypothesis, we performed whole-genome sequencing on pools of hybrid genotypes with either high or low AsA fruit. Pool-GWAS (genome-wide association study) revealed a single Quantitative Trait Locus (QTL) spanning more than 5 Mbp on chromosome 26, which we denote as qAsA26.1. A co-dominant PCR marker was used to validate this association in four diploid (A. chinensis × A. eriantha) × A. chinensis backcross families, showing that the A. eriantha allele at this locus increases fruit AsA levels by 250 mg/100 g fresh weight. Inspection of genome composition and recombination in other A. chinensis genetic maps confirmed that the qAsA26.1 region bears hallmarks of suppressed recombination. The molecular fingerprint of this locus was examined in leaves of backcross validation families by RNA sequencing (RNASEQ). This confirmed strong allelic expression bias across this region as well as differential expression of transcripts on other chromosomes. This evidence suggests that the region harbouring qAsA26.1 constitutes a supergene, which may condition multiple pleiotropic effects on metabolism.

19.
BMC Genomics ; 19(1): 257, 2018 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-29661190

RESUMEN

BACKGROUND: Most published genome sequences are drafts, and most are dominated by computational gene prediction. Draft genomes typically incorporate considerable sequence data that are not assigned to chromosomes, and predicted genes without quality confidence measures. The current Actinidia chinensis (kiwifruit) 'Hongyang' draft genome has 164 Mb of sequences unassigned to pseudo-chromosomes, and omissions have been identified in the gene models. RESULTS: A second genome of an A. chinensis (genotype Red5) was fully sequenced. This new sequence resulted in a 554.0 Mb assembly with all but 6 Mb assigned to pseudo-chromosomes. Pseudo-chromosomal comparisons showed a considerable number of translocation events have occurred following a whole genome duplication (WGD) event some consistent with centromeric Robertsonian-like translocations. RNA sequencing data from 12 tissues and ab initio analysis informed a genome-wide manual annotation, using the WebApollo tool. In total, 33,044 gene loci represented by 33,123 isoforms were identified, named and tagged for quality of evidential support. Of these 3114 (9.4%) were identical to a protein within 'Hongyang' The Kiwifruit Information Resource (KIR v2). Some proportion of the differences will be varietal polymorphisms. However, as most computationally predicted Red5 models required manual re-annotation this proportion is expected to be small. The quality of the new gene models was tested by fully sequencing 550 cloned 'Hort16A' cDNAs and comparing with the predicted protein models for Red5 and both the original 'Hongyang' assembly and the revised annotation from KIR v2. Only 48.9% and 63.5% of the cDNAs had a match with 90% identity or better to the original and revised 'Hongyang' annotation, respectively, compared with 90.9% to the Red5 models. CONCLUSIONS: Our study highlights the need to take a cautious approach to draft genomes and computationally predicted genes. Our use of the manual annotation tool WebApollo facilitated manual checking and correction of gene models enabling improvement of computational prediction. This utility was especially relevant for certain types of gene families such as the EXPANSIN like genes. Finally, this high quality gene set will supply the kiwifruit and general plant community with a new tool for genomics and other comparative analysis.


Asunto(s)
Actinidia/genética , Genoma de Planta , Genes de Plantas , Genotipo , Anotación de Secuencia Molecular , Proteínas de Plantas/genética
20.
Rev. senol. patol. mamar. (Ed. impr.) ; 31(1): 12-19, ene.-mar. 2018. tab, graf
Artículo en Español | IBECS | ID: ibc-174314

RESUMEN

Introducción. El cáncer de mama en la mujer joven constituye cerca del 5-10% de los cánceres de mama. Recientes estudios han demostrado un aumento de la incidencia de cáncer de mama en la mujer joven pero es posible que estos resultados no sean aplicables a nuestro entorno. El objetivo del presente estudio fue analizar si en nuestro entorno ha habido un aumento real de la incidencia. Material y métodos. Se utilizaron los datos del registro poblacional de tumores de mama de la provincia de Castellón (Comunidad Valenciana, España), correspondientes al Hospital Universitario General de Castellón en el periodo 1995-2013. Se establecieron 3grupos: < 45 años, de 45 a 69 años y > 69 años. Se realizó otra división en menores y mayores de 40 años. Resultados. De los 1.416 casos analizados, 178 eran menores de 45 años (12,6%), 886 (62,6%) tenían entre 45 y 69 años, y 352 (24,9%) tenían > 69 años. Del total, 87 pacientes fueron menores de 40 años (6,1%). El número de casos diagnosticados entre los 45 y los 69 años se ha visto incrementado de manera progresiva. Por el contrario, el número de casos diagnosticados en pacientes menores de 45 años se mantuvo prácticamente constante durante todos los años de estudio. La incidencia en mujeres menores de 40 años se mantuvo casi constante durante los años de estudio. Conclusión. No se ha podido demostrar en nuestro entorno y en el periodo estudiado un aumento de incidencia en el número de casos de mujeres jóvenes, tanto cuando se establecieron los puntos de corte en 40 años o en 45 años


Introduction. Breast cancer in young women represents only 5-10% of breast cancers. Recent studies have demonstrated an increasing incidence of breast cancer in young women, but these results may not apply in our population. The objective of this study was to analyse whether there has been a real increase in the incidence of breast cancer in young women in our population. Material and methods. Data were retrieved from the Castellon Cancer Registry (C. Valenciana, Spain), a population-based cancer registry. Data from tumours diagnosed in Castellon General Hospital between 1995 and 2013 were used to conduct this study. We defined 3groups of patients: <45 years; 45-69 years and >69 years. Another analysis was performed, using a cutoff at 40 years. Results. Of the 1,416 patients analysed, 178 were aged <45 years (12.6%), 886 (62.6%) were aged between 45 and 69 years and 352 (24.9%) were > 69 years; 87 patients were <40 years old (6.1%). The number of incident breast cancer patients significantly increased in the group aged 45-69 years. However, the number of incident cases remained constant during the study period for both patients aged <45 years and those aged <40 years. Conclusion. We did not find an increase in the incidence of breast cancer in young women in our population in the period analysed, or in women aged <45 years or <40 years old


Asunto(s)
Humanos , Femenino , Adulto , Persona de Mediana Edad , Neoplasias de la Mama/epidemiología , Pronóstico , Evaluación de Necesidades/tendencias , Perfil de Impacto de Enfermedad , Incidencia , Factores de Edad
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