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Kritické srovnání režimů náhrady nemajetkové újmy a vzniklé dvojkolejnosti / Critical comparison ofcompensation schemes for non-pecuniary harmand incurred duplicationTázler, Jakub January 2020 (has links)
1 Critical comparison of compensation schemes for non-pecuniary harm and incurred duplication Abstract The Diploma thesis deals with critical comparison of compensation schemes for non-pecuniary harm and incurred duplication. The aim is to describe how non-pecuniary harm is compensated in case of health-related harm, with particular regard to comparison of schemes according to Civil Code and Labour Code. This description and critical comparison of both schemes leads to reflection, that this incurred duplication is not in accordance with the constitutional values, and that, in the future, changes will be needed, so that this accordance would be achieved. The thesis is divided into six chapters. The first chapter defines basic terms, with whom it tis worked in the text - harm. What is that, when is it compensated, how is it laid down in Civil Code and Labour Code. The second chapter deals with the history and development of compensation for non-pecuniary harm in case of health-related harm. Next chapter describes key document for calculation of the amount of compensation - Supreme Court's methodology and the Government Regulation used for accidents at work. In this chapter there are mentioned two other legislations, Civil service employment Act and Professional soldiers' Act. Chapter "incurred duplication and...
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A Broad Analysis of Tandemly Arrayed Genes in the Genomes of Human, Mouse, and RatShoja, Valia 20 December 2006 (has links)
Tandemly arrayed genes (TAG) play an important functional and physiological role in the genome. Most previous studies have focused on individual TAG families in a few species, yet a broad characterization of TAGs is not available. We identified all the TAGs in the genomes of human, chimp, mouse, and rat and performed a comprehensive analysis of TAG distribution, TAG sizes, TAG gene orientations and intergenic distances, and TAG gene functions. TAGs account for about 14-17% of all the genomic genes and nearly one third of all the duplicated genes in the four genomes, highlighting the predominant role that tandem duplication plays in gene duplication. For all species, TAG distribution is highly heterogeneous along chromosomes and some chromosomes are enriched with TAG forests while others are enriched with TAG deserts. The majority of TAGs are of size two for all genomes, similar to the previous findings in C. elegans, A. thaliana, and O. sativa, suggesting that it is a rather general phenomenon in eukaryotes.
The comparison with the genome patterns shows that TAG members have a significantly higher proportion of parallel gene orientation in all species, corroborating Graham's claim that parallel orientation is the preferred form of orientation in TAGs. Moreover, TAG members with parallel orientation tend to be closer to each other than all neighboring genes with parallel orientation in the genome. The analysis of GO function indicate that genes with receptor or binding activities are significantly over-represented by TAGs. Simulation reveals that random gene rearrangements have little effect on the statistics of TAGs for all genomes. It is noteworthy to mention that gene family sizes are significantly correlated with the extent of tandem duplication, suggesting that tandem duplication is a preferred form of duplication, especially in large families.
There has not been any systematic study of TAG genes' expression patterns in the genome. Taking advantage of recent large-scale microarray data, we were able to study expression divergence of some of the TAGs of size two in human and mouse for which the expression data is available and examine the effect of sequence divergence, gene orientation, and physical proximity on the divergence of gene expression patterns. Our results show that there is a weak negative correlation between sequence divergence and expression similarity between the two members of a TAG, and also a weak negative correlation between physical proximity of two genes and their expression similarity. No significant relationship was detected between gene orientation and expression similarity. Moreover, we compared the expression breadth of upstream and downstream duplicate copies and found that downstream duplicate does not show significantly narrower expression breadth. We also compared TAG gene pairs with their neighboring non-TAG pairs for both physical proximity and expression similarity. Our results show that TAG gene pairs do not show any distinct differences in the two aspects from their neighboring gene pairs, suggesting that sufficient divergence has occurred to these duplicated genes during evolution and their original similarity conferred by duplication has decayed to a level that is comparable to their surrounding regions. / Master of Science
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Evolutionary history and diversification of duplicated fatty-acyl elongase genes of Atlantic salmon (Salmo salar)Carmona-Antoñanzas, Greta E. January 2014 (has links)
Background: The Atlantic salmon, Salmo salar L., is a prominent member of the Salmonidae family, and has been the focus of intense research because of its environmental and economic significance as an iconic sporting species and its global importance as an aquaculture species. Furthermore, salmonids constitute ideal organisms for the study of evolution by gene duplication as they are pseudotetraploid descendants of a common ancestor whose genome was duplicated some 25 to 100 million years ago. Whole-genome duplication is considered a major evolutionary force capable of creating vast amounts of new genetic material for evolution to act upon, promoting speciation by acquisition of new traits. Recently, large-scale comparison of paralogous genes in Atlantic salmon suggested that asymmetrical selection was acting on a significant proportion of them. However, to elucidate the physiological consequences of gene and genome duplications, studies integrating molecular evolution and functional biology are crucial. To this end, sequence and molecular analyses were performed on duplicated Elovl5 fatty-acyl elongases of Atlantic salmon, as they are responsible for a rate-limiting reaction in the elongation process of long-chain polyunsaturated fatty acids (LC-PUFA), critical components of all vertebrates. The aim of the research presented here was to investigate the role of gene duplication as an evolutionary process capable of creating genetic novelty, and to identify the potential ecological and physiological implications. Results: Linkage analyses indicated that both fatty-acyl elongases segregated independently and located elovl5 duplicates on different linkage groups. Genetic mapping using microsatellites identified in each elovl5 locus assigned elovl5a and elovl5b to chromosomes ssa28 and ssa13, respectively. In silico sequence analysis and selection tests indicated that both salmon Elovl5 proteins were subject to purifying selection, in agreement with previous results showing indistinguishable substrate specificities. Gene expression and promoter analysis indicated that Elovl5 duplicates differed in response to dietary lipids and tissue expression profile. Lipid biosynthesis and metabolic gene expression profiling performed in Atlantic salmon SHK-1 cells, suggested that the control of lipid homeostasis in fish is similar to that described in higher vertebrates, and revealed the particular importance of Lxr and Srebp transcription factors (TFs) in the regulation of LC-PUFA biosynthetic enzymes. Sequence comparison of upstream promoter regions of elovl5 genes showed intense differences between duplicates. Promoter functional analysis by co-transfection and transcription factor transactivation showed that both elovl5 duplicates were upregulated by Srebp overexpression. However, elovl5b exhibited a higher response and its promoter contained a duplication of a region containing response elements for Srebp and NF-Y cofactors. Furthermore, these studies indicated an Lxr/Rxr dependant response of elovl5a, which was not observed in elovl5b. Analysis of the genomic sequences of elovl5 duplicates by comparison to various sequence databases showed an asymmetrical distribution of transposable elements (TEs) in both introns and promoter regions. Further comparison to introns of the single elovl5 gene in pike indicated much higher TE distribution in salmon genes compared to the pike. Conclusions: Although not conclusive, the most parsimonious origin for the salmon elovl5 duplicates is that they are derived from a WGD event. This conclusion is also supported by the close similarity of two elovl5 paralogs in the recently available rainbow trout genome. Regardless of their origin, Atlantic salmon elovl5 genes have been efficiently retained in the genome under strong functional constraints indicating a physiological requirement for both enzymes to be functionally active. In contrast, upstream promoter regions have strongly diverged from one another, indicating a relaxation of purifying selection following the duplication event. This divergence of cis-regulatory regions has resulted in regulatory diversification of the elovl5 duplicates and regulatory neofunctionalisation of elovl5a, which displayed a novel Lxr/Rxr-dependant response not described in sister or other vertebrate lineages. Promoter analysis indicated that the observed elovl5 differential response to dietary variation could be partly attributed to varying transcriptional regulation driven by lipid-modulated TFs. The distribution of TEs in elvol5 genes of Atlantic salmon shows a clear increase in TE mobilisation after the divergence of esocids and salmonids. This must have occurred after the elongase duplication and thus the salmonid WGD event and contributes to the observed regulatory divergence of elovl5 paralogs.
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Molecular study of Metal Tolerance Protein 1(MTP1) and Plant Defensins Type I (PDF1) gene sub-families : inference on their role in evolution of zinc hypertolerance in Arabidopsis halleri / Molecular study of Metal Tolerance Protein 1(MTP1) and Plant Defensins Type I (PDF1) gene sub-families : contribution à la compréhension des mécanismes moléculaires évolutifs liés à l'acquisition de la tolérance au zinc chez Arabidopsis halleriShahzad, Zaigham 09 July 2010 (has links)
A. halleri, est une espèce modèle pour l'étude des mécanismes moléculaires liés à l'évolution des caractères d'hypertolérance au zinc et d'hyperaccumulation de ce métal, car elle est phylogénétiquement proche d'A. thaliana qui est sensible au zinc et non-accumulatrice. Dans ce travail, nous avons caractérisé comparativement chez A. thaliana et chez A. halleri, deux sous-familles de gènes liés à l'homéostasie du zinc et ou à sa tolérance: Metal Tolérance Protein 1 (MTP1) et Plant Defensin type I (PDF1). Notre analyse génomique montre que le nombre de ces gènes est plus élevé chez A. halleri que chez A. thaliana confortant l'hypothèse actuelle reliant les duplications de gènes chez A. halleri à l'acquisition de son caractère d'hypertolérance. Mais, les résultats de nos études fonctionnelles ne vont pas dans ce sens, car ils montrent que, par exemple, certaines protéines AhMTP1 et AhPDF1 induisent une tolérance au zinc faible voire nulle lorsqu'elles sont testées dans la levure. Mais le résultat le plus marquant est que les transcrits de plusieurs gènes AhMTP1 et AhPDF1 ne sont pas détectables ou bien sont faiblement accumulés dans la plante. Nos résultats montrent donc que les gènes de ces sous-familles ne sont pas équivalents en ce qui concerne leur fonction dans la tolérance au zinc suggérant ainsi qu'ils sont le sujet de devenirs évolutifs différents. En dehors de leur contribution à la compréhension des mécanismes moléculaires qui sous-tendent l'évolution de la tolérance au zinc chez A. halleri, nos travaux sont également porteurs de développements biotechnologiques appliqués au zinc dans les domaines de la phytoremédiation et de la biofortification / A. halleri, is a model species to study molecular evolutionary mechanisms related to zinc hypertolerance and hyperaccumulation, due to its close relatedness with A. thaliana which is zinc sensitive and non-accumulator. Here, we comparatively characterised in both species, two zinc homeostasis and/or zinc tolerance related genes sub-families: the Metal Tolerance Protein 1 (MTP1) and the Plant defensins type I (PDF1). Genomic analyses revealed that the copy number of these genes is increased in A. halleri compared to A. thaliana. It was thus tempting to relate the acquisition of zinc hypertolerance in A. halleri to these gene duplications. However, the assumption was invalidated by functional analyses. For instance, some of the AhMTP1 or AhPDF1 proteins induced weak or no zinc tolerance to yeast. More importantly, transcripts of many AhMTP1 or AhPDF1 genes were either not accumulated or were very poorly expressed in A. halleri. These results indicate that different members of these gene sub-families are not equally functional. It is thus expected that these gene duplicates are undergoing different evolutionary fates regarding zinc tolerance. Besides helping to understand the molecular evolutionary mechanisms, studying zinc-related genes in A. halleri may also help developing strategies like phytoremediation and biofortification.
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Génomique comparée et évolutive chez les graminées : Cas particulier des micro-ARNAbrouk, Michael 19 December 2012 (has links)
Les Poaceae aussi appelées Graminées forment une importante famille botanique regroupant près de 12 000 espèces en plus de 700 genres dont les céréales. Cette famille présente un intérêt économique majeur car elle est importante dans la nutrition humaine et animale. De ce fait, cette famille a été très étudiée en génomique comparée depuis les années 1990 révélant une grande conservation de la structure de leur génome depuis leur divergence d’un ancêtre commun. Avec le séquençage de Brachypodium distachyon en 2009, nous avons réalisé l’analyse de son génome par l’identification de douze blocs de synténie avec les génomes séquencés du riz, du sorgho et du maïs ainsi que sept blocs de duplications partagées entre ces graminées. Ces données nous ont permis de suggérer que les cinq chromosomes modernes de Brachypodium sont issus de l’ancêtre commun des graminées constitué de douze chromosomes et ayant subi sept fusions au cours de l’évolution. Ces travaux nous ont permis de confirmer un possible génome ancêtre des graminées constitué de cinq chromosomes porteurs de près de 10 000 gènes et d’une taille minimale de près de 35Mb. Ensuite, sur la base des résultats de génomique comparée, nous nous sommes intéressés à l’évolution des différentes familles de micro-ARN (miARN). La comparaison de ces ARN non-codants réalisée pour le riz, le sorgho, le maïs et Brachypodium montre une conservation de cette famille chez les graminées avec 50% d’orthologues et 20% de paralogues. Sur la base des résultats de paléogénomique, nous avons proposé une modélisation de l’évolution des miARN qui corrobore l’hypothèse d’une origine très ancienne de ce mécanisme de « gene silencing ». Au-delà des nouvelles connaissances fondamentales générées au cours de ce travail de thèse sur l’évolution des génomes de graminées, les résultats que nous avons obtenus ont des applications potentielles dans le domaine de l’amélioration variétale, comme avec par exemple la possibilité de définir des marqueurs moléculaires de type COS (Conserved Orthologous Set). Ces marqueurs COS ont été mis en oeuvre pour l’étude de caractères agronomiques d’intérêt dans des espèces dont le génome n’est pas encore complètement séquencé comme le blé. / Poaceae also called Grasses are an important botanical family consisting in nearly 12,000 species in over 700 genres including cereals. This family is of major economic interest because it comprises cereals that are among the most important crops for human and animal nutrition. This family has been extensively studied in comparative genomics since the 1990s and showed a high degree of gene conservation among species since they diverged from a common ancestor. With the sequencing of Brachypodium distachyon in 2009, we performed an analysis of its genome by the identification of twelve synteny blocks with the sequenced genomes of rice, sorghum and maize and seven duplications blocks shared with these last grass species. These data allowed us to suggest the five chromosomes of Brachypodium are from the common ancestor composed of twelve chromosomes and having undergone seven fusions during the evolution. This work allowed us to confirm a possible grass ancestor with five chromosomes carrying almost 10,000 genes with a size of 35Mb. Then, based on these comparative genomics results, we studied more particularly the evolution of different families of microRNAs (miRNAs). The comparison of non-coding RNA from rice, sorghum, maize and Brachypodium showed conservation into this family for the grass species with 50% of orthologs and 20% of paralogs. Based on the paleogenomics results, we proposed an evolutionary scenario of miRNA genes, which supports the hypothesis of an ancient origin of this gene silencing mechanism in plants. Beyond the fundamental knowledge generated on the evolution of grass genomes during this PhD, these results have potential applications in breeding, for example with the possibility to identify COS (Conserved Orthologous Set) molecular markers. Such COS markers have been used for the study of agronomic traits in species not completely sequenced as wheat.
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Molecular and Clinical Characterization of Syndromes Associated With Intellectual DisabilityWentzel, Christian January 2013 (has links)
Intellectual disability (ID) affects approximately 1-3% of the population and is defined as having an IQ below 70 as well as a significant limitation in adaptive behavior. The implementation of chromosomal microarrays (CMA) into the field of clinical genetics has revolutionized the ability to find genetic aberrations responsible for different genetic disorders. Importantly. these technologies have allowed several new microdeletion and microduplication aberrations to be identified that otherwise would have escaped detection using more conventional methods. Finding the genetic etiology of a syndrome and its association to the phenotype is paramount to better health care, provision of tailored therapy, presymptomatic screening, accurate prognosis, recurrence risk evaluation and in some cases prenatal testing. Despite the plethora of new information available, there are still a number of clinical and genetic features we do not fully understand. The aim of this work was to identify regions and syndromes associated with ID by CMA analysis and to make a detailed clinical description of the affected patients’ phenotype. In paper I we studied the 22q11.2 duplication syndrome and presented two familial cases with a description of both their genotype and phenotype. Additionally, 36 cases harboring the duplication were reviewed to further delineate the phenotype of the syndrome. In paper II, we revealed two unrelated patients with a deletion at 6q14.1-q15 and a distinct phenotype. Together with one previously reported patient our study suggests that a novel, clinically recognizable microdeletion syndrome exists in these patients. In paper III the phenotype and genotype of six unrelated patients with partially overlapping microdeletions at 10p12.31-p11.21 were described. Taken together with a previously reported patient we propose that these findings represent a new contiguous gene syndrome. In paper IV, two sisters; one presenting with two tandem interstitial duplications and the other a large deletion over the same region (6q13-q16) were reported. The reason for the CNVs was a maternal de novo translocation. This is the first case describing the genotype and phenotype of this duplicated region at 6q13-q16. In conclusion, four different genetic aberrations involved in the etiology of ID and their corresponding phenotypes and candidate genes have been characterized.
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Algorithmes pour la reconstruction de génomes ancestrauxGagnon, Yves 05 1900 (has links)
L’inférence de génomes ancestraux est une étape essentielle pour l’étude de l’évolution
des génomes. Connaissant les génomes d’espèces éteintes, on peut proposer des
mécanismes biologiques expliquant les divergences entre les génomes des espèces modernes.
Diverses méthodes visant à résoudre ce problème existent, se classant parmis deux
grandes catégories : les méthodes de distance et les méthodes de synténie. L’état de l’art
des distances génomiques ne permettant qu’un certain répertoire de réarrangements pour
le moment, les méthodes de synténie sont donc plus appropriées en pratique.
Nous proposons une méthode de synténie pour la reconstruction de génomes ancestraux
basée sur une définition relaxée d’adjacences de gènes, permettant un contenu en
gène inégal dans les génomes modernes causé par des pertes de gènes de même que des
duplications de génomes entiers (DGE). Des simulations sont effectuées, démontrant
une capacité de former une solution assemblée en un nombre réduit de régions ancestrales
contigües par rapport à d’autres méthodes tout en gardant une bonne fiabilité. Des
applications sur des données de levures et de plantes céréalières montrent des résultats
en accord avec d’autres publications, notamment la présence de fusion imbriquée de
chromosomes pendant l’évolution des céréales. / Ancestral genome inference is a decisive step for studying genome evolution. Knowing
genomes from extinct species, one can propose biological mecanisms explaining
divergences between extant species genomes.
Various methods classified in two categories have been developped : distance based
methods and synteny based methods. The state of the art of distance based methods only
permit a certain repertoire of genomic rearrangements, thus synteny based methods are
more appropriate in practice for the time being.
We propose a synteny method for ancestral genome reconstruction based on a relaxed
defenition of gene adjacencies, permitting unequal gene content in extant genomes
caused by gene losses and whole genome duplications (WGD). Simulations results demonstrate
our method’s ability to form a more assembled solution rather than a collection of
contiguous ancestral regions (CAR) with respect to other methods, while maintaining a
good reliability. Applications on data sets from yeasts and cereal species show results
agreeing with other publications, notably the existence of nested chromosome fusion
during the evolution of cereals.
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Variation in length of proteins by repeats and disorder regionsSagit, Rauan January 2013 (has links)
Protein-coding genes evolve together with their genome and acquire changes, some of which affect the length of their protein products. This explains why equivalent proteins from different species can exhibit length differences. Variation in length of proteins during evolution arguably presents a large number of possibilities for improvement and innovation of protein structure and function. In order to contribute to an increased understanding of this process, we have studied variation caused by tandem domain duplications and insertions or deletions of intrinsically disordered residues. The study of two proteins, Nebulin and Filamin, together with a broader study of long repeat proteins (>10 domain repeats), began by confirming that tandem domains evolve by internal duplications. Next, we show that vertebrate Nebulins evolved by duplications of a seven-domain unit, yet the most recent duplications utilized different gene parts as duplication units. However, Filamin exhibits a checkered duplication pattern, indicating that duplications were followed by similarity erosions that were hindered at particular domains due to the presence of equivalent binding motifs. For long repeat proteins, we found that human segmental duplications are over-represented in long repeat genes. Additionally, domains that have formed long repeats achieved this primarily by duplications of two or more domains at a time. The study of homologous protein pairs from the well-characterized eukaryotes nematode, fruit fly and several fungi, demonstrated a link between variation in length and variation in the number of intrinsically disordered residues. Next, insertions and deletions (indels) estimated from HMM-HMM pairwise alignments showed that disordered residues are clearly more frequent among indel than non-indel residues. Additionally, a study of raw length differences showed that more than half of the variation in fungi proteins is composed of disordered residues. Finally, a model of indels and their immediate surroundings suggested that disordered indels occur in already disordered regions rather than in ordered regions. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: In press. Paper 4: Manuscript.</p>
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Algorithmes pour la reconstruction de génomes ancestrauxGagnon, Yves 05 1900 (has links)
L’inférence de génomes ancestraux est une étape essentielle pour l’étude de l’évolution
des génomes. Connaissant les génomes d’espèces éteintes, on peut proposer des
mécanismes biologiques expliquant les divergences entre les génomes des espèces modernes.
Diverses méthodes visant à résoudre ce problème existent, se classant parmis deux
grandes catégories : les méthodes de distance et les méthodes de synténie. L’état de l’art
des distances génomiques ne permettant qu’un certain répertoire de réarrangements pour
le moment, les méthodes de synténie sont donc plus appropriées en pratique.
Nous proposons une méthode de synténie pour la reconstruction de génomes ancestraux
basée sur une définition relaxée d’adjacences de gènes, permettant un contenu en
gène inégal dans les génomes modernes causé par des pertes de gènes de même que des
duplications de génomes entiers (DGE). Des simulations sont effectuées, démontrant
une capacité de former une solution assemblée en un nombre réduit de régions ancestrales
contigües par rapport à d’autres méthodes tout en gardant une bonne fiabilité. Des
applications sur des données de levures et de plantes céréalières montrent des résultats
en accord avec d’autres publications, notamment la présence de fusion imbriquée de
chromosomes pendant l’évolution des céréales. / Ancestral genome inference is a decisive step for studying genome evolution. Knowing
genomes from extinct species, one can propose biological mecanisms explaining
divergences between extant species genomes.
Various methods classified in two categories have been developped : distance based
methods and synteny based methods. The state of the art of distance based methods only
permit a certain repertoire of genomic rearrangements, thus synteny based methods are
more appropriate in practice for the time being.
We propose a synteny method for ancestral genome reconstruction based on a relaxed
defenition of gene adjacencies, permitting unequal gene content in extant genomes
caused by gene losses and whole genome duplications (WGD). Simulations results demonstrate
our method’s ability to form a more assembled solution rather than a collection of
contiguous ancestral regions (CAR) with respect to other methods, while maintaining a
good reliability. Applications on data sets from yeasts and cereal species show results
agreeing with other publications, notably the existence of nested chromosome fusion
during the evolution of cereals.
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An analysis of salmonid RNA sequences and implications for salmonid evolutionBrown, Gordon David 01 April 2008 (has links)
This work addresses two areas of computational biology: automation of sequence
processing and an assessment of the evidence for a hypothesized salmonid
genome based on an analysis of a set of expressed sequence tags.
Three problem areas in sequence processing are addressed in the first half of
the work. Chapter 3 describes an accurate technique for trimming of vector,
adapter and poly(A) sequence. Chapter 4 suggests methods for verifying the
accuracy of assembled mRNA transcripts despite a large number of
chimeras in the cDNA clone libraries. Chapter 5 is concerned with the problem
of estimating the number of transcripts in a tissue or cDNA library, concluding
that computational and statistical techniques are inadequate to estimate the
quantity accurately.
The hypothesized salmonid genome duplication has been widely accepted since
1984. If it occurred, it should have left evidence in the form of many
paralogous pairs of genes, all at approximately the same degree of sequence
divergence. To assess this question, several hundred thousand ESTs were
assembled into transcripts, compared to each other to find homologs, and
the evolutionary distances of the homologs represented as a histogram.
Evidence of a single evolutionary event was not seen. The same procedure
was applied to Xenopus laevis, which has a well-established recent
genome duplication, and Danio rerio, which is known not to have had
one. In those cases, the evidence for or against a genome duplication
appeared exactly as predicted. The conclusion is that if the salmonid
genome duplication occurred, some force altered its evolutionary development
subsequently to mask the duplication, but also that a genome duplication is not
necessary to explain the observed pattern of homolog distances.
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