isolated populations
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Author(s):  
F. Tiso ◽  
T. N. Koorenhof-Scheele ◽  
E. Huys ◽  
J. H. A. Martens ◽  
A. O. de Graaf ◽  
...  

AbstractAcute myeloid leukemia (AML) is a highly heterogeneous disease showing dynamic clonal evolution patterns over time. Various subclones may be present simultaneously and subclones may show a different expansion pattern and respond differently to applied therapies. It is already clear that immunophenotyping and genetic analyses may yield overlapping, but also complementary information. Detailed information on the genetic make-up of immunophenotypically defined subclones is however scarce. We performed error-corrected sequencing for 27 myeloid leukemia driver genes in 86, FACS-sorted immunophenotypically characterized normal and aberrant subfractions in 10 AML patients. We identified three main scenarios. In the first group of patients, the two techniques were equally well characterizing the malignancy. In the second group, most of the isolated populations did not express aberrant immunophenotypes but still harbored several genetic aberrancies, indicating that the information obtained only by immunophenotyping would be incomplete. Vice versa, one patient was identified in which genetic mutations were found only in a small fraction of the immunophenotypically defined malignant populations, indicating that the genetic analysis gave an incomplete picture of the disease. We conclude that currently, characterization of leukemic cells in AML by molecular and immunophenotypic techniques is complementary, and infer that both techniques should be used in parallel in order to obtain the most complete view on the disease.


Author(s):  
Cristian Barros-Diaz ◽  
Silvia Vela ◽  
Abel Gallo-Perez ◽  
Manuel Chiquito ◽  
Xavier Cornejo ◽  
...  

The existence of chromatic aberrations such as leucism or albinism is the result of inbreeding in isolated populations of wild local fauna and is associated with environmental stressors. This anomaly may reduce survival rates. There are many cases of leucism in wildlife, but overall, it is considered very rare. In neotropical primates, there have been records of leucism but previously, in howler monkeys was unknown. In this article, we report for the first time leucistic young individuals of Mantled howler monkeys Alouatta palliata, subspecies A. p. aequatorialis in an isolated remanent of tropical dry forest in southwestern Ecuador, namely Cerro Blanco Protective Forest. In total, we found two individuals, we named them Albita (a female) and Japu (a male). We also include a spatial analysis of the covert forest loss between 2000 to 2020. The report of individuals with leucism, may imply inbreeding because of isolated populations. Thus, immediate management strategies must be considered to significantly increase connectivity with other populations of howler monkeys.


2022 ◽  
Vol 17 (1) ◽  
Author(s):  
Aria Setoodeh ◽  
Samareh Panjeh-Shahi ◽  
Fariba Bahmani ◽  
Fatemeh Vand-Rajabpour ◽  
Nazanin Jalilian ◽  
...  

Abstract Objective Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy syndrome (APECED) is a rare autosomal recessive systemic autoimmune disease caused by mutations in the autoimmune regulator (AIRE) gene. Incidence of this genetic disorder is estimated at 1/90,000–200,000 worldwide and 1/6500–9000 in genetically isolated populations such as Iran. Here, we investigated AIRE gene mutations in eight independent Iranian non-Jewish families. Methods We sequenced the coding regions of the AIRE gene and documented mutations which were further confirmed in respective parents. Results In total, 11 cases from 8 independent families were recruited. Mucosal candidiasis, Addison’s disease and hypoparathyroidism were the most common clinical manifestations in these patients. One novel homozygous splice acceptor mutation (c.308-1G>C), and one novel heterozygous stop-gain mutation (c.1496delC) combined with a known heterozygous c.232T>C missense mutation were found. Moreover, we observed previously described splice donor (c.1095+2T>A), frameshift (c.967-979del), stop-gain (c.415C>T), and missense (c.62C>T) mutations among the patients. All results were co-segregated in parents. Conclusion Here, we reported two novel mutations in the AIRE gene leading to APECED. Our data could provide insight into the phenotypic and genotypic spectrum of APECED in the non-Jewish Iranian population. These findings, in addition to future functional assays, can elucidate disease-causing mechanisms related to the AIRE gene and assist in genetic counseling and diagnosis.


2022 ◽  
Author(s):  
Alice Michel ◽  
Riana Minocher ◽  
Peter Niehoff ◽  
Yuhong Li ◽  
Kevin Nota ◽  
...  

Conservation efforts tend to focus on populations that are genetically differentiated without paying attention to their ecological differentiation. However, isolated populations may be ecologically unique, an important aspect for the design of appropriate conservation measures for endangered species. Here we investigate the interplay between diet and gut microbiome in several geographically isolated and genetically differentiated populations of the critically endangered Grauer's gorilla. We find that dietary and gut microbial profiles are population-specific, likely due to geographic isolation and environmental differences. In addition, social groups within each population also differed in diet and, to a lesser extent, in gut microbial composition and diversity. Individuals at low elevation consumed a larger variety of plant taxa than those at high elevation, consistent with the notion that dietary choice is constrained by food availability that changes with elevation. Despite no detectable correlation between the diet and gut microbiome in richness or evenness, dietary and gut microbial composition covaried significantly. As we did not find evidence for an effect of genetic relatedness on the composition of the gut microbiome of Grauer's gorillas, this pattern is likely a result of long-term social, ecological, and geographic factors acting on both diet and microbiome. These results reveal that isolated and genetically distinct populations of Grauer's gorillas are also ecologically distinct, highlighting the need to dedicate separate conservation efforts for each population.


2021 ◽  
Vol 17 (2) ◽  
pp. 116-135
Author(s):  
Rebeca Marques Correia da Rocha ◽  
Marcelo Seidel Fiorotti

Ecological corridors are territorial strips that aim to reduce the impacts of fragmentation of ecosystems, restoring the interconnection between them, in order to facilitate the movement of species, enabling seed dispersal and gene exchange between isolated populations. The relevance of the theme lies in the contribution to sustainable urbanism, aligning with biophilia, with benefits for living beings, including humans, with better walking conditions, thermal and psychological comfort. The general objective of the work was to delineate an urban ecological corridor in the continental portion of the city of Vitória/ES, in order to connect three isolated Environmental Protection Zones and benefit their essential occupants: the human species, the flora and the fauna. Exploratory studies and field visits were conducted, supported by Urbanism and Ecology literature, based on the definition of the connection axes and the recomposition of road profiles. The result achieved is an ecological corridor adapted to the existing roads, from the intensification of forestation and the implementation of gantries and elevated walkways for animal crossings. The insertion of aerial crossings and biodiversity corridors will bring a differential to the quality of life and ecological diversity for the local population.


Pathogens ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1650
Author(s):  
Lisa Segeritz ◽  
Ole Anders ◽  
Tomma Lilli Middelhoff ◽  
Deliah Tamsyn Winterfeld ◽  
Pavlo Maksimov ◽  
...  

The Eurasian lynx (Lynx lynx) represents an endangered wild felid species. In Germany, it currently occurs in three isolated populations in and around the Harz Mountains, the Palatinate Forest and the Bavarian Forest. Lynx parasitic infections affect animal health and might have an influence on population performance. Therefore, we investigated the protozoan and helminth fauna of free-ranging Eurasian lynx of the Harz population with emphasis on zoonotic parasites. Individual scat samples (n = 24) were collected from wild animals between 2019 and 2021 in the Harz National Park and surrounding areas. In total, 15 taxa of endoparasites were detected, including seven nematodes (i.e., Aelurostrongylus abstrusus, Angiostrongylus spp., Uncinaria stenocephala, Toxascaris leonina, Toxocara cati, Cylicospirura spp. and Capillaria spp.), one cestode (Diphyllobothriidae) and one trematode (Heterophylidae) as well as six protozoans (i.e., Cystoisospora rivolta, Cystoisospora felis, Toxoplasma gondii/Hammondia spp., Sarcocystis spp., Giardia intestinalis and Cryptosporidium spp.). Moreover, first-stage larvae (L1) of spurious lungworm, Protostrongylus pulmonalis, originating from lagomorph preys were identified. This work represents the first report on patent A. abstrusus and Angiostrongylus spp. infections in wild German Eurasian lynxes. Some of the identified parasites represent relevant pathogens for lynxes, circulating between these carnivorous definitive hosts and a variety of mammalian and invertebrate intermediate hosts, e.g., Sarcocystis spp., T. gondii/Hammondia spp., T. cati, T. leonina, A. abstrusus and Angiostrongylus spp., while others are considered exclusively pathogenic for wild felids (e.g., Cylicospirura spp., C. rivolta, C. felis). This study provides insights in the occurrence of zooanthroponotically relevant metazoan (i.e., T. cati and U. stenocephala) and protozoan (i.e., G. intestinalis) species in free-ranging lynx. The present work should be considered as a baseline study for future monitoring surveys on endoparasites circulating in wild Eurasian lynx for appropriate management practices in lynx conservation strategies in Europe.


PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0255752
Author(s):  
Kris A. Christensen ◽  
Eric B. Rondeau ◽  
Dionne Sakhrani ◽  
Carlo A. Biagi ◽  
Hollie Johnson ◽  
...  

Pink salmon (Oncorhynchus gorbuscha) adults are the smallest of the five Pacific salmon native to the western Pacific Ocean. Pink salmon are also the most abundant of these species and account for a large proportion of the commercial value of the salmon fishery worldwide. A two-year life history of pink salmon generates temporally isolated populations that spawn either in even-years or odd-years. To uncover the influence of this genetic isolation, reference genome assemblies were generated for each year-class and whole genome re-sequencing data was collected from salmon of both year-classes. The salmon were sampled from six Canadian rivers and one Japanese river. At multiple centromeres we identified peaks of Fst between year-classes that were millions of base-pairs long. The largest Fst peak was also associated with a million base-pair chromosomal polymorphism found in the odd-year genome near a centromere. These Fst peaks may be the result of a centromere drive or a combination of reduced recombination and genetic drift, and they could influence speciation. Other regions of the genome influenced by odd-year and even-year temporal isolation and tentatively under selection were mostly associated with genes related to immune function, organ development/maintenance, and behaviour.


Genetics ◽  
2021 ◽  
Author(s):  
Reine U Protacio ◽  
Tresor O Mukiza ◽  
Mari K Davidson ◽  
Wayne P Wahls

Abstract It has long been known (circa 1917) that environmental conditions, as well as speciation, can affect dramatically the frequency distribution of Spo11/Rec12-dependent meiotic recombination. Here, by analyzing DNA sequence-dependent meiotic recombination hotspots in the fission yeast Schizosaccharomyces pombe, we reveal a molecular basis for these phenomena. The impacts of changing environmental conditions (temperature, nutrients, osmolarity) on local rates of recombination are mediated directly by DNA site-dependent hotspots (M26, CCAAT, Oligo-C). This control is exerted through environmental condition-responsive signal transduction networks (involving Atf1, Pcr1, Php2, Php3, Php5, Rst2). Strikingly, individual hotspots modulate rates of recombination over a very broad dynamic range in response to changing conditions. They can range from being quiescent to being highly proficient at promoting activity of the basal recombination machinery (Spo11/Rec12 complex). Moreover, each different class of hotspot functions as an independently controlled rheostat; a condition that increases the activity of one class can decrease the activity of another class. Together, the independent modulation of recombination rates by each different class of DNA site-dependent hotspots (of which there are many) provides a molecular mechanism for highly dynamic, large-scale changes in the global frequency distribution of meiotic recombination. Because hotspot-activating DNA sites discovered in fission yeast are conserved functionally in other species, this process can also explain the previously enigmatic, Prdm9-independent, evolutionarily rapid changes in hotspot usage between closely related species, subspecies, and isolated populations of the same species.


2021 ◽  
Author(s):  
Samantha V. Beck ◽  
Gary R. Carvalho ◽  
Ian McCarthy ◽  
Walter Hanks ◽  
Robert Evans ◽  
...  

AbstractAquatic species throughout the world are threatened by extinction in many parts of their range, particularly in their most southerly distributions. Arctic charr (Salvelinus alpinus) is a Holarctic species with a distribution that includes the glacial lakes of North Wales, towards it southern limit. To date, no genetic studies have been conducted to determine the genetic health of the three remaining native Arctic charr populations in North Wales, despite exposure to stocking and adverse environmental and ecological conditions. We used seven microsatellite loci to determine whether: 1) genetic differentiation existed between native populations; 2) translocated populations from Llyn Peris were genetically similar to the historically connected Llyn Padarn population; and 3) hatchery supplementation negatively impacted genetic diversity in Llyn Padarn. All three native populations retained their genetic integrity, with Llyn Bodlyn showing high levels of divergence (FST = 0.26 ± 0.02SD) as well as low genetic diversity (HO 0.30) compared to remaining populations (HO 0.64 ± 0.14SD). Although evidence suggests that stocking increased the effective population size of Llyn Padarn in the short term without impacting genetic diversity, the long term effects of such practices are yet to be seen. Results provide baseline data for conservation management, and highlight the need for protection of small isolated populations that are being negatively impacted by the processes of genetic drift due to escalating anthropogenic pressures. Continual monitoring of both Arctic charr and their habitats using a combination of methods will increase the likelihood that these threatened and iconic populations will persist in the future.


2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. 662-663
Author(s):  
Sarah Hubner ◽  
Akankshya Chataut ◽  
Marcia Shade ◽  
Ann Fruhling ◽  
Natalie Manley ◽  
...  

Abstract Remaining community-dwelling is a goal for most aging adults; however, this may necessitate assistance from caregivers. To reduce burden and improve adult autonomy, recent technological advancements have provided various supports. These advancements may improve quality of life (QOL) while also enhancing psychological/physical well-being for adults and caregivers. To investigate relationships between technology, QOL, and caregiver burden, needs assessments with focus groups were utilized. Four older adult focus groups (N=20) and three caregiver focus groups (N=12) were convened. Older adult participants, aged 64-83 years (M=73.1,SD=5.3), were 50% female and generally white (90%). Caregiver participants, aged 31-78 years (M=61.9,SD=12.6), were majority female (83%) and generally white (92%). Because of the ongoing COVID-19 pandemic, focus groups were conducted via Zoom video-conferencing. Thematic analyses revealed major themes of privacy, transportation, and interest in streamlined technologies. Throughout groups, privacy was consistently described; participants were either 1) apathetic, noting absence of privacy or 2) hyper-vigilant about security, citing privacy as a major barrier to utilization. Transportation, specifically self-driving/enhanced vehicles, emerged as a focus for future technologies as a means to reduce care burden and improve personal autonomy/QOL. In general, participants noted that major barriers to technology use included complexity and cost; persons expressed interest in simpler/cheaper devices. This study indicates varied interest in technology while exposing barriers to use. Additionally, the methodology demonstrates the utility of technology (e.g., Zoom) in accessing vulnerable and/or isolated populations. Overall, understanding barriers to technology use and adoption informs upcoming developments and may improve accessibility and usefulness in future systems/devices.


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