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Beata Ujvari - One of the best experts on this subject based on the ideXlab platform.
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multiple paternity and precocial breeding in wild tasmanian devils Sarcophilus harrisii marsupialia dasyuridae
Biological Journal of The Linnean Society, 2019Co-Authors: Tracey Russell, Thomas Madsen, Tamara Keeley, Amanda Lane, Judy Clarke, Carolyn J Hogg, Katrina M Morris, Beata UjvariAbstract:Polyandry, a common reproductive strategy in various animal species, has potential female benefits, which include enhanced offspring fitness. Benefits can be direct, such as reduced risk of male infanticide of offspring, or indirect, such as increased genetic diversity of offspring and the acquisition of 'good genes'. Multiple paternity of litters has been recorded in numerous marsupial species but has not been reported in Tasmanian devils, Sarcophilus harrisii (Boitard). We investigated whether multiple paternity occurred in litters within a wild population of Tasmanian devils. Using major histocompatibility complex-linked and neutral microsatellite markers, the paternity of nine litters was analysed. We found multiple paternity in four out of nine litters and that yearling (> 1, < 2 years old) male devils were siring offspring. This is the first record of multiple paternity and of male precocial breeding in wild Tasmanian devils. To date, there are no data relating to the subsequent survival of devils from single- vs. multiple-sired litters; therefore, we do not know whether multiple paternity increases offspring survival in the wild. These results have implications for the Tasmanian devil captive insurance programme, because group housing can lead to multiple-sired litters, making the maintenance of genetic diversity over time difficult to manage.
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oncogenesis as a selective force adaptive evolution in the face of a transmissible cancer
BioEssays, 2018Co-Authors: Tracey Russell, Frederic Thomas, Nynke Raven, Rodrigo Hamede, Thomas Madsen, Beata UjvariAbstract:Similar to parasites, malignant cells exploit the host for energy, resources and protection, thereby impairing host health and fitness. Although cancer is widespread in the animal kingdom, its impact on life history traits and strategies have rarely been documented. Devil facial tumour disease (DFTD), a transmissible cancer, afflicting Tasmanian devils (Sarcophilus harrisii), provides an ideal model system to monitor the impact of cancer on host life-history, and to elucidate the evolutionary arms-race between malignant cells and their hosts. Here we provide an overview of parasite-induced host life history (LH) adaptations, then both phenotypic plasticity of LH responses and changes in allele frequencies that affect LH traits of Tasmanian devils in response to DFTD are discussed. We conclude that akin to parasites, cancer can directly and indirectly affect devil LH traits and trigger host evolutionary responses. Consequently, it is important to consider oncogenic processes as a selective force in wildlife.
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Oncogenesis as a Selective Force
BioEssays, 2018Co-Authors: Tracey Russell, Frederic Thomas, Nynke Raven, Rodrigo Hamede, Thomas Madsen, Beata UjvariAbstract:Similar to parasites, malignant cells exploit the host for energy, resources and protection, thereby impairing host health and fitness. Although cancer is widespread in the animal kingdom, its impact on life history traits and strategies have rarely been documented. Devil facial tumour disease (DFTD), a transmissible cancer, afflicting Tasmanian devils (Sarcophilus harrisii), provides an ideal model system to monitor the impact of cancer on host life-history, and to elucidate the evolutionary arms-race between malignant cells and their hosts. Here we provide an overview of parasite-induced host life history (LH) adaptations, then both phenotypic plasticity of LH responses and changes in allele frequencies that affect LH traits of Tasmanian devils in response to DFTD are discussed. We conclude that akin to parasites, cancer can directly and indirectly affect devil LH traits and trigger host evolutionary responses. Consequently, it is important to consider oncogenic processes as a selective force in wildlife.
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Immunoglubolin dynamics and cancer prevalence in Tasmanian devils (Sarcophilus harrisii)
Scientific reports, 2016Co-Authors: Beata Ujvari, David Pemberton, Rodrigo Hamede, Menna E Jones, Sarah Peck, Katherine Belov, Thomas MadsenAbstract:Immunoglobulins such as IgG and IgM have been shown to induce anti-tumour cytotoxic activity. In the present study we therefore explore total serum IgG and IgM expression dynamics in 23 known-aged Tasmanian devils (Sarcophilus harrisii) of which 9 where affected by Devil Facial Tumour Disease (DFTD). DFTD is clonally transmissible cancer that has caused massive declines in devil numbers. Our analyses revealed that IgM and IgG expression levels as well as IgM/IgG ratios decreased with increasing devil age. Neither age, sex, IgM nor IgG expression levels affected devil DFTD status in our analyses. However, devils with increased IgM relative to IgG expression levels had significantly lower DFTD prevalence. Our results therefore suggest that IgM/IgG ratios may play an important role in determining devil susceptibility to DFTD. We consequently propose that our findings warrant further studies to elucidate the underpinning(s) of devil IgM/IgG ratios and DFTD status.
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Characterization of antibody V segment diversity in the Tasmanian devil (Sarcophilus harrisii).
Veterinary immunology and immunopathology, 2015Co-Authors: Beata Ujvari, Katherine BelovAbstract:The Tasmanian devil (Sarcophilus harrisii) immune system has recently been under scrutiny because of the emergence of a contagious cancer, which has decimated devil numbers. Here we provide a comprehensive description of the Tasmanian devil immunoglobulin variable regions. We show that heavy chain variable (VH) and light chain variable (VL) repertoires are similar to those described in other marsupial taxa: VL diversity is high, but VH diversity is restricted and belongs only to clan III. As in other mammals, one VH and one Vλ germline family and multiple incomplete Vκ germline sequences were identified in the genome. High Vκ variation was observed in transcripts and we predict that it may have arisen by gene conversion and/or somatic mutations, as it does not appear to have originated from germline variation. Phylogenetic analyses revealed that devil VL gene segments are highly complex and ancient, with some lineages predating the separation of marsupials and eutherians. These results indicate that although the evolutionary history of immune genes lead to the expansions and contractions of immune gene families between different mammalian lineages, some of the ancestral immune gene variants are still maintained in extant species. A high degree of similarity was found between devil and other marsupial VH segments, demonstrating that they originated from a common clade of closely related sequences. The VL families had a higher variation than VH both between and within species. We suggest that, similar to other studied marsupial species, the complex VL segment repertoire compensates for the limited VH diversity in Tasmanian devils.
Thomas Madsen - One of the best experts on this subject based on the ideXlab platform.
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multiple paternity and precocial breeding in wild tasmanian devils Sarcophilus harrisii marsupialia dasyuridae
Biological Journal of The Linnean Society, 2019Co-Authors: Tracey Russell, Thomas Madsen, Tamara Keeley, Amanda Lane, Judy Clarke, Carolyn J Hogg, Katrina M Morris, Beata UjvariAbstract:Polyandry, a common reproductive strategy in various animal species, has potential female benefits, which include enhanced offspring fitness. Benefits can be direct, such as reduced risk of male infanticide of offspring, or indirect, such as increased genetic diversity of offspring and the acquisition of 'good genes'. Multiple paternity of litters has been recorded in numerous marsupial species but has not been reported in Tasmanian devils, Sarcophilus harrisii (Boitard). We investigated whether multiple paternity occurred in litters within a wild population of Tasmanian devils. Using major histocompatibility complex-linked and neutral microsatellite markers, the paternity of nine litters was analysed. We found multiple paternity in four out of nine litters and that yearling (> 1, < 2 years old) male devils were siring offspring. This is the first record of multiple paternity and of male precocial breeding in wild Tasmanian devils. To date, there are no data relating to the subsequent survival of devils from single- vs. multiple-sired litters; therefore, we do not know whether multiple paternity increases offspring survival in the wild. These results have implications for the Tasmanian devil captive insurance programme, because group housing can lead to multiple-sired litters, making the maintenance of genetic diversity over time difficult to manage.
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oncogenesis as a selective force adaptive evolution in the face of a transmissible cancer
BioEssays, 2018Co-Authors: Tracey Russell, Frederic Thomas, Nynke Raven, Rodrigo Hamede, Thomas Madsen, Beata UjvariAbstract:Similar to parasites, malignant cells exploit the host for energy, resources and protection, thereby impairing host health and fitness. Although cancer is widespread in the animal kingdom, its impact on life history traits and strategies have rarely been documented. Devil facial tumour disease (DFTD), a transmissible cancer, afflicting Tasmanian devils (Sarcophilus harrisii), provides an ideal model system to monitor the impact of cancer on host life-history, and to elucidate the evolutionary arms-race between malignant cells and their hosts. Here we provide an overview of parasite-induced host life history (LH) adaptations, then both phenotypic plasticity of LH responses and changes in allele frequencies that affect LH traits of Tasmanian devils in response to DFTD are discussed. We conclude that akin to parasites, cancer can directly and indirectly affect devil LH traits and trigger host evolutionary responses. Consequently, it is important to consider oncogenic processes as a selective force in wildlife.
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Oncogenesis as a Selective Force
BioEssays, 2018Co-Authors: Tracey Russell, Frederic Thomas, Nynke Raven, Rodrigo Hamede, Thomas Madsen, Beata UjvariAbstract:Similar to parasites, malignant cells exploit the host for energy, resources and protection, thereby impairing host health and fitness. Although cancer is widespread in the animal kingdom, its impact on life history traits and strategies have rarely been documented. Devil facial tumour disease (DFTD), a transmissible cancer, afflicting Tasmanian devils (Sarcophilus harrisii), provides an ideal model system to monitor the impact of cancer on host life-history, and to elucidate the evolutionary arms-race between malignant cells and their hosts. Here we provide an overview of parasite-induced host life history (LH) adaptations, then both phenotypic plasticity of LH responses and changes in allele frequencies that affect LH traits of Tasmanian devils in response to DFTD are discussed. We conclude that akin to parasites, cancer can directly and indirectly affect devil LH traits and trigger host evolutionary responses. Consequently, it is important to consider oncogenic processes as a selective force in wildlife.
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Immunoglubolin dynamics and cancer prevalence in Tasmanian devils (Sarcophilus harrisii)
Scientific reports, 2016Co-Authors: Beata Ujvari, David Pemberton, Rodrigo Hamede, Menna E Jones, Sarah Peck, Katherine Belov, Thomas MadsenAbstract:Immunoglobulins such as IgG and IgM have been shown to induce anti-tumour cytotoxic activity. In the present study we therefore explore total serum IgG and IgM expression dynamics in 23 known-aged Tasmanian devils (Sarcophilus harrisii) of which 9 where affected by Devil Facial Tumour Disease (DFTD). DFTD is clonally transmissible cancer that has caused massive declines in devil numbers. Our analyses revealed that IgM and IgG expression levels as well as IgM/IgG ratios decreased with increasing devil age. Neither age, sex, IgM nor IgG expression levels affected devil DFTD status in our analyses. However, devils with increased IgM relative to IgG expression levels had significantly lower DFTD prevalence. Our results therefore suggest that IgM/IgG ratios may play an important role in determining devil susceptibility to DFTD. We consequently propose that our findings warrant further studies to elucidate the underpinning(s) of devil IgM/IgG ratios and DFTD status.
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evolution of a contagious cancer epigenetic variation in devil facial tumour disease
Proceedings of The Royal Society B: Biological Sciences, 2013Co-Authors: Beata Ujvari, Thomas Madsen, Sarah Peck, Annemaree Pearse, Collette Harmsen, Robyn Taylor, Stephen Pyecroft, Anthony T Papenfuss, Katherine BelovAbstract:The emergence of Devil Facial Tumour Disease (DFTD), a highly contagious cancer, is driving Tasmanian devils ( Sarcophilus harrisii ) to extinction. The cancer is a genetically and chromosomally stable clonal cell line which is transmitted by biting during social interactions. In the present study, we explore the Devil Facial Tumour (DFT) epigenome and the genes involved in DNA methylation homeostasis. We show that tumour cells have similar levels of methylation to peripheral nerves, the tissue from which DFTD originated. We did not observe any strain or region-specific epimutations. However, we revealed a significant increase in hypomethylation in DFT samples over time ( p p p
Sarah Peck - One of the best experts on this subject based on the ideXlab platform.
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Salmonella in captive and wild Tasmanian devils (Sarcophilus harrisii) in Tasmania.
Australian veterinary journal, 2020Co-Authors: Michael, Sarah Peck, M Harlock, Billie Lazenby, David PembertonAbstract:Translocation of Tasmanian devils (Sarcophilus harrisii) is a common strategy for recovery of the species as carried out by the Save the Tasmanian Devil Program. Dasyurids including the endangered Tasmanian devil are well known to asymptomatically harbour the zoonotic bacteria Salmonella enterica in their intestinal tracts. Testing for Salmonella is a routine component of pretranslocation health testing, so a statewide microbiological survey of captive and wild devils was implemented in order to understand prevalence and common Salmonella serotypes, and inform decision-making when positive cultures are identified. This preliminary study identified a significantly higher proportion of Salmonella isolations in wild compared with captive devils. Mississippi and Typhimurium were the most common serotypes, followed by Lexington, Bovismorbificans, Kottbus and Amsterdam. Given the common finding of Salmonella in wild devils and the range of serotypes involved, in addition to numerous isolations in domestic species and humans, it is unlikely that the release of small numbers of captive devils to the wild in Tasmania poses a significant risk to the destination ecosystem. Ongoing monitoring of devils is required as the stress of acclimatisation could predispose devils to clinical disease. Appropriate personal protective attire is pertinent to protect personnel handling animals from this zoonotic infection.
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Anaplastic meningioma in a Tasmanian devil (Sarcophilus harrisii)
Veterinary Record Case Reports, 2019Co-Authors: Jessica Elbert, Sarah Peck, Dane Hayes, Jim Taylor, Jodi D. SmithAbstract:A seven-year-old male captive Tasmanian devil was euthanased after presenting with hindlimb ataxia and generalised muscle wasting. On necropsy, an irregular, cream-coloured, firm, 1 cm mass was detected on the dorsal surface of the left olfactory bulb. The mass was composed of pleomorphic neoplastic cells arranged in nests and lobules with occasional pseudorosette formation, and evinced invasion of underlying neural parenchyma. By immunohistochemistry, neoplastic cells were strongly positive for vimentin and cytokeratin AE1/AE3, variably positive for S-100 and neuron-specific enolase, and negative for calretinin, chromogranin A, synaptophysin, glial fibrillar acidic protein and neurofilament protein. Periodic acid-Schiff and Grimelius stains were also negative. Based on histopathological and immunohistochemical findings, the neoplasm was classified as an anaplastic meningioma.
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Molecular characterization of Cryptosporidium and Giardia from the Tasmanian devil (Sarcophilus harrisii)
PloS one, 2017Co-Authors: Liana F. Wait, Sarah Peck, Samantha Fox, Michelle L. PowerAbstract:The Tasmanian devil (Sarcophilus harrisii) is a carnivorous marsupial found only in the wild in Tasmania, Australia. Tasmanian devils are classified as endangered and are currently threatened by devil facial tumour disease, a lethal transmissible cancer that has decimated the wild population in Tasmania. To prevent extinction of Tasmanian devils, conservation management was implemented in 2003 under the Save the Tasmanian Devil Program. This study aimed to assess if conservation management was altering the interactions between Tasmanian devils and their parasites. Molecular tools were used to investigate the prevalence and diversity of two protozoan parasites, Cryptosporidium and Giardia, in Tasmanian devils. A comparison of parasite prevalence between wild and captive Tasmanian devils showed that both Cryptosporidium and Giardia were significantly more prevalent in wild devils (p < 0.05); Cryptosporidium was identified in 37.9% of wild devils but only 10.7% of captive devils, while Giardia was identified in 24.1% of wild devils but only 0.82% of captive devils. Molecular analysis identified the presence of novel genotypes of both Cryptosporidium and Giardia. The novel Cryptosporidium genotype was 98.1% similar at the 18S rDNA to Cryptosporidium varanii (syn. C. saurophilum) with additional samples identified as C. fayeri, C. muris, and C. galli. Two novel Giardia genotypes, TD genotype 1 and TD genotype 2, were similar to G. duodenalis from dogs (94.4%) and a Giardia assemblage A isolate from humans (86.9%). Giardia duodenalis BIV, a zoonotic genotype of Giardia, was also identified in a single captive Tasmanian devil. These findings suggest that conservation management may be altering host-parasite interactions in the Tasmanian devil, and the presence of G. duodenalis BIV in a captive devil points to possible human-devil parasite transmission.
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A review of parasites in the Tasmanian devil (Sarcophilus harrisii)
Biodiversity and Conservation, 2017Co-Authors: Liana F. Wait, Sarah Peck, Michelle L. PowerAbstract:Threatened by devil facial tumour disease, the Tasmanian devil ( Sarcophilus harrisii ), a carnivorous marsupial confined to Tasmania, Australia, is the subject of conservation management under the Save the Tasmanian Devil Program. Conservation actions such as captive breeding and translocation may impact upon parasite ecology, presenting risk of increased disease through stress and impaired immunity, and by exposing hosts to parasites to which they are immunologically naïve. Given the importance of parasites to ecosystem function, it has been argued from a biodiversity perspective that parasites should be conserved in their own right. In this review we describe current knowledge, and limitations in our knowledge, of Tasmanian devil parasites. We then discuss the potential for changes in host–parasite interactions as a result of host-population decline and conservation management, both generally and with examples from the Tasmanian devil. The review closes with a recommendation for a systematic evaluation of parasites in captive and wild devils to aid conservation of this host–parasite system in its entirety.
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A review of parasites in the Tasmanian devil (Sarcophilus harrisii)
Biodiversity and Conservation, 2016Co-Authors: Liana F. Wait, Sarah Peck, Samantha Fox, Michelle L. PowerAbstract:Threatened by devil facial tumour disease, the Tasmanian devil (Sarcophilus harrisii), a carnivorous marsupial confined to Tasmania, Australia, is the subject of conservation management under the Save the Tasmanian Devil Program. Conservation actions such as captive breeding and translocation may impact upon parasite ecology, presenting risk of increased disease through stress and impaired immunity, and by exposing hosts to parasites to which they are immunologically naive. Given the importance of parasites to ecosystem function, it has been argued from a biodiversity perspective that parasites should be conserved in their own right. In this review we describe current knowledge, and limitations in our knowledge, of Tasmanian devil parasites. We then discuss the potential for changes in host–parasite interactions as a result of host-population decline and conservation management, both generally and with examples from the Tasmanian devil. The review closes with a recommendation for a systematic evaluation of parasites in captive and wild devils to aid conservation of this host–parasite system in its entirety.
Menna E Jones - One of the best experts on this subject based on the ideXlab platform.
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Age-related variation in the trophic characteristics of a marsupial carnivore, the Tasmanian devil Sarcophilus harrisii.
Ecology and evolution, 2020Co-Authors: Olivia Bell, Rodrigo Hamede, Menna E Jones, Manuel Ruiz-aravena, Stuart Bearhop, Robbie A. McdonaldAbstract:Age-related changes in diet have implications for competitive interactions and for predator–prey dynamics, affecting individuals and groups at different life stages. To quantify patterns of variation and ontogenetic change in the diets of Tasmanian devils Sarcophilus harrisii, a threatened marsupial carnivore, we analyzed variation in the stable isotope composition of whisker tissue samples taken from 91 individual devils from Wilmot, Tasmania from December 2014 to February 2017. Both δ13C and δ15N decreased with increasing age in weaned Tasmanian devils, indicating that as they age devils rely less on small mammals and birds, and more on large herbivores. Devils
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The genomic basis of tumor regression in Tasmanian devils (Sarcophilus harrisii)
Genome biology and evolution, 2018Co-Authors: Mark J. Margres, Rodrigo Hamede, Menna E Jones, Manuel Ruiz-aravena, Austin H. Patton, Matthew F. Lawrance, Brian W. Davis, Elaine A. Ostrander, Sarah A. Hendricks, Hamish MccallumAbstract:Understanding the genetic basis of disease-related phenotypes, such as cancer susceptibility, is crucial for the advancement of personalized medicine. Although most cancers are somatic in origin, a small number of transmissible cancers have been documented. Two such cancers have emerged in the Tasmanian devil (Sarcophilus harrisii) and now threaten the species with extinction. Recently, cases of natural tumor regression in Tasmanian devils infected with the clonally contagious cancer have been detected. We used whole-genome sequencing and FST-based approaches to identify the genetic basis of tumor regression by comparing the genomes of seven individuals that underwent tumor regression with those of three infected individuals that did not. We found three highly differentiated candidate genomic regions containing several genes related to immune response and/or cancer risk, indicating that the genomic basis of tumor regression was polygenic. Within these genomic regions, we identified putative regulatory variation in candidate genes but no nonsynonymous variation, suggesting that natural tumor regression may be driven, at least in part, by differential host expression of key loci. Comparative oncology can provide insight into the genetic basis of cancer risk, tumor development, and the pathogenicity of cancer, particularly due to our limited ability to monitor natural, untreated tumor progression in human patients. Our results support the hypothesis that host immune response is necessary for triggering tumor regression, providing candidate genes that may translate to novel treatments in human and nonhuman cancers.
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Sarcophilus harrisii dasyuromorphia dasyuridae
Mammalian Species, 2017Co-Authors: Robert K Rose, Nick Mooney, David Pemberton, Menna E JonesAbstract:The Tasmanian devil, Sarcophilus harrisii (Boitard, 1842), the largest surviving marsupial carnivore, is endemic to Tasmania. The size of a small stocky dog, with males weighing 9 kg and females 6 kg, S. harrisii is a scavenger of large mammals and opportunistic predator of vertebrates. Life span in the wild averaged 3–4 years until the late 1990s when a fatal cancer, transmitted by bites, began devastating populations, primarily adults. Devil Facial Tumor Disease (DFTD), a soft-tissue neoplasm usually seen 1st on the head, invariably kills within 6 months of the appearance of symptoms. In the 20 years since the appearance of DFTD, S. harrisii has gone from a species of "Least Concern" to one "Threatened" and potentially on the path to extinction
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Immunoglubolin dynamics and cancer prevalence in Tasmanian devils (Sarcophilus harrisii)
Scientific reports, 2016Co-Authors: Beata Ujvari, David Pemberton, Rodrigo Hamede, Menna E Jones, Sarah Peck, Katherine Belov, Thomas MadsenAbstract:Immunoglobulins such as IgG and IgM have been shown to induce anti-tumour cytotoxic activity. In the present study we therefore explore total serum IgG and IgM expression dynamics in 23 known-aged Tasmanian devils (Sarcophilus harrisii) of which 9 where affected by Devil Facial Tumour Disease (DFTD). DFTD is clonally transmissible cancer that has caused massive declines in devil numbers. Our analyses revealed that IgM and IgG expression levels as well as IgM/IgG ratios decreased with increasing devil age. Neither age, sex, IgM nor IgG expression levels affected devil DFTD status in our analyses. However, devils with increased IgM relative to IgG expression levels had significantly lower DFTD prevalence. Our results therefore suggest that IgM/IgG ratios may play an important role in determining devil susceptibility to DFTD. We consequently propose that our findings warrant further studies to elucidate the underpinning(s) of devil IgM/IgG ratios and DFTD status.
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Hematologic and serum biochemical reference intervals for wild Tasmanian devils (Sarcophilus harrisii)
Veterinary clinical pathology, 2015Co-Authors: Sarah Peck, Rodrigo Hamede, Menna E Jones, Ross Corkrey, Paul J. CanfieldAbstract:Background: The Tasmanian devil ( Sarcophilus harrisii ) is a carnivorous marsupial threatened with extinction by a fatally infectious cancer known as devil facial tumor disease (DFTD). Conservation efforts including captive breeding and island translocations are underway to address this threat. Objectives: The objectives of this study were to determine hematologic and serum biochemical reference intervals (RI) to aid in health assessment of Tasmanian devils, and to examine seasonal, sex, reproductive status and age variations. Methods: We collected jugular blood samples from individual wild Tasmanian devils at 2 different locations over a 2-year period to determine hematologic and serum biochemical RI by nonparametric methods using the central 0.95 fraction. Results: A total of 307 blood samples were collected from 187 devils. Significant age differences were found for ALP, CK, cholesterol, calcium, phosphate, albumin, globulins, albumin: globulin ratio, and glucose. Significant differences between sexes were observed for AST, creatinine, and potassium. Significant seasonal or reproductive status variation in adult males or breeding females were observed for PCV, HGB, RBC, MCHC, MCH, MCV, neutrophils and lymphocytes, fibrinogen, total plasma protein, AST, ALP, ALT, GLDH, bilirubin, urea, calcium, chloride, total protein, albumin, A:G, and glucose. Conclusions: Many of the differences observed between subgroups can be explained by growth requirements, reproductive demands, and seasonal effects on activity. This study has determined comprehensive RI for the Tasmanian devil, which will be used to assess animals targeted for captive breeding and translocations, or affected by DFTD.
Rodrigo Hamede - One of the best experts on this subject based on the ideXlab platform.
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Age-related variation in the trophic characteristics of a marsupial carnivore, the Tasmanian devil Sarcophilus harrisii.
Ecology and evolution, 2020Co-Authors: Olivia Bell, Rodrigo Hamede, Menna E Jones, Manuel Ruiz-aravena, Stuart Bearhop, Robbie A. McdonaldAbstract:Age-related changes in diet have implications for competitive interactions and for predator–prey dynamics, affecting individuals and groups at different life stages. To quantify patterns of variation and ontogenetic change in the diets of Tasmanian devils Sarcophilus harrisii, a threatened marsupial carnivore, we analyzed variation in the stable isotope composition of whisker tissue samples taken from 91 individual devils from Wilmot, Tasmania from December 2014 to February 2017. Both δ13C and δ15N decreased with increasing age in weaned Tasmanian devils, indicating that as they age devils rely less on small mammals and birds, and more on large herbivores. Devils
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The genomic basis of tumor regression in Tasmanian devils (Sarcophilus harrisii)
Genome biology and evolution, 2018Co-Authors: Mark J. Margres, Rodrigo Hamede, Menna E Jones, Manuel Ruiz-aravena, Austin H. Patton, Matthew F. Lawrance, Brian W. Davis, Elaine A. Ostrander, Sarah A. Hendricks, Hamish MccallumAbstract:Understanding the genetic basis of disease-related phenotypes, such as cancer susceptibility, is crucial for the advancement of personalized medicine. Although most cancers are somatic in origin, a small number of transmissible cancers have been documented. Two such cancers have emerged in the Tasmanian devil (Sarcophilus harrisii) and now threaten the species with extinction. Recently, cases of natural tumor regression in Tasmanian devils infected with the clonally contagious cancer have been detected. We used whole-genome sequencing and FST-based approaches to identify the genetic basis of tumor regression by comparing the genomes of seven individuals that underwent tumor regression with those of three infected individuals that did not. We found three highly differentiated candidate genomic regions containing several genes related to immune response and/or cancer risk, indicating that the genomic basis of tumor regression was polygenic. Within these genomic regions, we identified putative regulatory variation in candidate genes but no nonsynonymous variation, suggesting that natural tumor regression may be driven, at least in part, by differential host expression of key loci. Comparative oncology can provide insight into the genetic basis of cancer risk, tumor development, and the pathogenicity of cancer, particularly due to our limited ability to monitor natural, untreated tumor progression in human patients. Our results support the hypothesis that host immune response is necessary for triggering tumor regression, providing candidate genes that may translate to novel treatments in human and nonhuman cancers.
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oncogenesis as a selective force adaptive evolution in the face of a transmissible cancer
BioEssays, 2018Co-Authors: Tracey Russell, Frederic Thomas, Nynke Raven, Rodrigo Hamede, Thomas Madsen, Beata UjvariAbstract:Similar to parasites, malignant cells exploit the host for energy, resources and protection, thereby impairing host health and fitness. Although cancer is widespread in the animal kingdom, its impact on life history traits and strategies have rarely been documented. Devil facial tumour disease (DFTD), a transmissible cancer, afflicting Tasmanian devils (Sarcophilus harrisii), provides an ideal model system to monitor the impact of cancer on host life-history, and to elucidate the evolutionary arms-race between malignant cells and their hosts. Here we provide an overview of parasite-induced host life history (LH) adaptations, then both phenotypic plasticity of LH responses and changes in allele frequencies that affect LH traits of Tasmanian devils in response to DFTD are discussed. We conclude that akin to parasites, cancer can directly and indirectly affect devil LH traits and trigger host evolutionary responses. Consequently, it is important to consider oncogenic processes as a selective force in wildlife.
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Oncogenesis as a Selective Force
BioEssays, 2018Co-Authors: Tracey Russell, Frederic Thomas, Nynke Raven, Rodrigo Hamede, Thomas Madsen, Beata UjvariAbstract:Similar to parasites, malignant cells exploit the host for energy, resources and protection, thereby impairing host health and fitness. Although cancer is widespread in the animal kingdom, its impact on life history traits and strategies have rarely been documented. Devil facial tumour disease (DFTD), a transmissible cancer, afflicting Tasmanian devils (Sarcophilus harrisii), provides an ideal model system to monitor the impact of cancer on host life-history, and to elucidate the evolutionary arms-race between malignant cells and their hosts. Here we provide an overview of parasite-induced host life history (LH) adaptations, then both phenotypic plasticity of LH responses and changes in allele frequencies that affect LH traits of Tasmanian devils in response to DFTD are discussed. We conclude that akin to parasites, cancer can directly and indirectly affect devil LH traits and trigger host evolutionary responses. Consequently, it is important to consider oncogenic processes as a selective force in wildlife.
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Immunoglubolin dynamics and cancer prevalence in Tasmanian devils (Sarcophilus harrisii)
Scientific reports, 2016Co-Authors: Beata Ujvari, David Pemberton, Rodrigo Hamede, Menna E Jones, Sarah Peck, Katherine Belov, Thomas MadsenAbstract:Immunoglobulins such as IgG and IgM have been shown to induce anti-tumour cytotoxic activity. In the present study we therefore explore total serum IgG and IgM expression dynamics in 23 known-aged Tasmanian devils (Sarcophilus harrisii) of which 9 where affected by Devil Facial Tumour Disease (DFTD). DFTD is clonally transmissible cancer that has caused massive declines in devil numbers. Our analyses revealed that IgM and IgG expression levels as well as IgM/IgG ratios decreased with increasing devil age. Neither age, sex, IgM nor IgG expression levels affected devil DFTD status in our analyses. However, devils with increased IgM relative to IgG expression levels had significantly lower DFTD prevalence. Our results therefore suggest that IgM/IgG ratios may play an important role in determining devil susceptibility to DFTD. We consequently propose that our findings warrant further studies to elucidate the underpinning(s) of devil IgM/IgG ratios and DFTD status.
