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1.
Front Immunol ; 14: 1215607, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37731500

RESUMEN

Background: Molecular diversity of virus-associated cervical cancer remains a relatively underexplored issue, and interrelations of immunologic and angiogenic features during the establishment of a particular landscape of the cervical cancer microenvironment are not well-characterized, especially for its earliest clinical stages, although this may provide insight into the mechanisms behind the differences in tumor aggressiveness, treatment responsiveness and prognosis. In this research, we were aimed at identifying transcriptomic landscapes of early-stage cervical carcinoma that differ substantially in their immune-related characteristics, patterns of signaling pathways and composition of the microenvironment in comparison with immediate precursor (intraepithelial) lesions. Methods: We performed the Illumina platform-based RNA sequencing using a panel of fresh tissue samples that included human papillomavirus-positive cervical intraepithelial neoplastic lesions (CIN), invasive squamous carcinoma of the cervix of FIGO IA1-IIB stages, and morphologically normal epithelium. The derived transcriptomic profiles were bioinformatically analyzed and compared by patterns of signaling pathway activation, distribution of tumor-infiltrating cell populations, and genomic regions involved. Result: According to hierarchical cluster analysis of the whole-transcriptome profiles, tissue samples were distributed between three groups, or gene expression patterns (the one comprising most pre-cancer cases and the other two encompassing mostly early-stage invasive cancer cases). Differentially expressed genes were retrieved in each intergroup pairwise comparison followed by Gene Ontology analysis. Gene set enrichment analysis of the two groups of tumor samples in comparison with the CIN group identified substantial differences in immunological and angiogenic properties between tumorous groups suggesting the development of different molecular phenotypes. Cell composition analysis confirmed the diverse changes in the abundancies of immune and non-immune populations and, accordingly, different impacts of the immune and stromal compartments on the tumor microenvironment in these two groups of tumors compared to CIN. Positional gene expression analysis demonstrated that the identified transcriptomic differences were linked to different chromosomal regions and co-localized with particular gene families implicated in immune regulation, inflammation, cell differentiation, and tumor invasion. Conclusions: Overall, detection of different transcriptomic patterns of invasive cervical carcinoma at its earliest stages supports the diverse impacts of immune response- and angiogenesis-related mechanisms on the onset of tumor invasion and progression. This may provide new options for broadening the applicability and increasing the efficiency of target anti-angiogenic and immune-based therapy of virus-associated cervical carcinoma.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/genética , Perfilación de la Expresión Génica , Transcriptoma , Carcinoma de Células Escamosas/genética , Inmunidad , Microambiente Tumoral/genética
2.
Genes (Basel) ; 14(3)2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36980891

RESUMEN

Pusa sibirica, the Baikal seal, is the only extant, exclusively freshwater, pinniped species. The pending issue is, how and when they reached their current habitat-the rift lake Baikal, more than three thousand kilometers away from the Arctic Ocean. To explore the demographic history and genetic diversity of this species, we generated a de novo chromosome-length assembly, and compared it with three closely related marine pinniped species. Multiple whole genome alignment of the four species compared with their karyotypes showed high conservation of chromosomal features, except for three large inversions on chromosome VI. We found the mean heterozygosity of the studied Baikal seal individuals was relatively low (0.61 SNPs/kbp), but comparable to other analyzed pinniped samples. Demographic reconstruction of seals revealed differing trajectories, yet remarkable variations in Ne occurred during approximately the same time periods. The Baikal seal showed a significantly more severe decline relative to other species. This could be due to the difference in environmental conditions encountered by the earlier populations of Baikal seals, as ice sheets changed during glacial-interglacial cycles. We connect this period to the time of migration to Lake Baikal, which occurred ~3-0.3 Mya, after which the population stabilized, indicating balanced habitat conditions.


Asunto(s)
Lagos , Phocidae , Animales , Phocidae/genética , Cariotipo
3.
Genes (Basel) ; 13(5)2022 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-35627305

RESUMEN

This study provides new data on the whole-exome sequencing of a cohort of children with autistic spectrum disorders (ASD) from an underexplored Russian population. Using both a cross-sectional approach involving a control cohort of the same ancestry and an annotation-based approach involving relevant public databases, we explored exonic single nucleotide variants and copy-number variation potentially involved in the manifestation of ASD. The study results reveal new potential ASD candidate-variants found in the studied Russian cohort and show a high prevalence of common ASD-associated genomic variants, especially those in the genes known to be associated with the manifestation of intellectual disabilities. Our screening of an ASD cohort from a previously understudied population allowed us to flag at least a few novel genes (IGLJ2, FAM21A, OR11H12, HIP1, PRAMEF10, and ZNF717) regarding their potential involvement in ASD.


Asunto(s)
Trastorno del Espectro Autista , Trastorno del Espectro Autista/genética , Niño , Estudios de Cohortes , Variaciones en el Número de Copia de ADN , Genómica , Humanos , Secuenciación del Exoma
4.
Evol Appl ; 15(3): 351-364, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35386395

RESUMEN

Captive breeding programmes represent the most intensive type of ex situ population management for threatened species. One example is the Cuvier's gazelle programme that started in 1975 with only four founding individuals, and after more than four decades of management in captivity, a reintroduction effort was undertaken in Tunisia in 2016, to establish a population in an area historically included within its range. Here, we aim to determine the genetic consequences of this reintroduction event by assessing the genetic diversity of the founder stock as well as of their descendants. We present the first whole-genome sequencing dataset of 30 Cuvier's gazelles including captive-bred animals, animals born in Tunisia after a reintroduction and individuals from a genetically unrelated Moroccan population. Our analyses revealed no difference between the founder and the offspring cohorts in genome-wide heterozygosity and inbreeding levels, and in the amount and length of runs of homozygosity. The captive but unmanaged Moroccan gazelles have the lowest genetic diversity of all genomes analysed. Our findings demonstrate that the Cuvier's gazelle captive breeding programme can serve as source populations for future reintroductions of this species. We believe that this study can serve as a starting point for global applications of genomics to the conservation plan of this species.

5.
Mol Ecol ; 31(10): 2898-2919, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35334142

RESUMEN

Species of the mustelid subfamily Guloninae inhabit diverse habitats on multiple continents, and occupy a variety of ecological niches. They differ in feeding ecologies, reproductive strategies and morphological adaptations. To identify candidate loci associated with adaptations to their respective environments, we generated a de novo assembly of the tayra (Eira barbara), the earliest diverging species in the subfamily, and compared this with the genomes available for the wolverine (Gulo gulo) and the sable (Martes zibellina). Our comparative genomic analyses included searching for signs of positive selection, examining changes in gene family sizes and searching for species-specific structural variants. Among candidate loci associated with phenotypic traits, we observed many related to diet, body condition and reproduction. For example, for the tayra, which has an atypical gulonine reproductive strategy of aseasonal breeding, we observed species-specific changes in many pregnancy-related genes. For the wolverine, a circumpolar hypercarnivore that must cope with seasonal food scarcity, we observed many changes in genes associated with diet and body condition. All types of genomic variation examined (single nucleotide polymorphisms, gene family expansions, structural variants) contributed substantially to the identification of candidate loci. This argues strongly for consideration of variation other than single nucleotide polymorphisms in comparative genomics studies aiming to identify loci of adaptive significance.


Asunto(s)
Mustelidae , Adaptación Fisiológica/genética , Animales , Genoma , Genómica , Mustelidae/genética , Fenotipo
6.
Gigascience ; 122022 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-37609916

RESUMEN

BACKGROUND: Inference of complex demographic histories is a source of information about events that happened in the past of studied populations. Existing methods for demographic inference typically require input from the researcher in the form of a parameterized model. With an increased variety of methods and tools, each with its own interface, the model specification becomes tedious and error-prone. Moreover, optimization algorithms used to find model parameters sometimes turn out to be inefficient, for instance, by being not properly tuned or highly dependent on a user-provided initialization. The open-source software GADMA addresses these problems, providing automatic demographic inference. It proposes a common interface for several likelihood engines and provides global parameters optimization based on a genetic algorithm. RESULTS: Here, we introduce the new GADMA2 software and provide a detailed description of the added and expanded features. It has a renovated core code base, new likelihood engines, an updated optimization algorithm, and a flexible setup for automatic model construction. We provide a full overview of GADMA2 enhancements, compare the performance of supported likelihood engines on simulated data, and demonstrate an example of GADMA2 usage on 2 empirical datasets. CONCLUSIONS: We demonstrate the better performance of a genetic algorithm in GADMA2 by comparing it to the initial version and other existing optimization approaches. Our experiments on simulated data indicate that GADMA2's likelihood engines are able to provide accurate estimations of demographic parameters even for misspecified models. We improve model parameters for 2 empirical datasets of inbred species.


Asunto(s)
Algoritmos , Investigadores , Humanos , Demografía , Probabilidad , Programas Informáticos
7.
J Hered ; 112(6): 540-548, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34146095

RESUMEN

The Puma lineage within the family Felidae consists of 3 species that last shared a common ancestor around 4.9 million years ago. Whole-genome sequences of 2 species from the lineage were previously reported: the cheetah (Acinonyx jubatus) and the mountain lion (Puma concolor). The present report describes a whole-genome assembly of the remaining species, the jaguarundi (Puma yagouaroundi). We sequenced the genome of a male jaguarundi with 10X Genomics linked reads and assembled the whole-genome sequence. The assembled genome contains a series of scaffolds that reach the length of chromosome arms and is similar in scaffold contiguity to the genome assemblies of cheetah and puma, with a contig N50 = 100.2 kbp and a scaffold N50 = 49.27 Mbp. We assessed the assembled sequence of the jaguarundi genome using BUSCO, aligned reads of the sequenced individual and another published female jaguarundi to the assembled genome, annotated protein-coding genes, repeats, genomic variants and their effects with respect to the protein-coding genes, and analyzed differences of the 2 jaguarundis from the reference mitochondrial genome. The jaguarundi genome assembly and its annotation were compared in quality, variants, and features to the previously reported genome assemblies of puma and cheetah. Computational analyzes used in the study were implemented in transparent and reproducible way to allow their further reuse and modification.


Asunto(s)
Felidae , Puma , Animales , Femenino , Genoma , Genómica , Masculino , Anotación de Secuencia Molecular , Puma/genética
8.
Curr Biol ; 31(13): 2929-2938.e5, 2021 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-33957077

RESUMEN

Species is the fundamental taxonomic unit in biology and its delimitation has implications for conservation. In giraffe (Giraffa spp.), multiple taxonomic classifications have been proposed since the early 1900s.1 However, one species with nine subspecies has been generally accepted,2 likely due to limited in-depth assessments, subspecies hybridizing in captivity,3,4 and anecdotal reports of hybrids in the wild.5 Giraffe taxonomy received new attention after population genetic studies using traditional genetic markers suggested at least four species.6,7 This view has been met with controversy,8 setting the stage for debate.9,10 Genomics is significantly enhancing our understanding of biodiversity and speciation relative to traditional genetic approaches and thus has important implications for species delineation and conservation.11 We present a high-quality de novo genome assembly of the critically endangered Kordofan giraffe (G. camelopardalis antiquorum)12 and a comprehensive whole-genome analysis of 50 giraffe representing all traditionally recognized subspecies. Population structure and phylogenomic analyses support four separately evolving giraffe lineages, which diverged 230-370 ka ago. These lineages underwent distinct demographic histories and show different levels of heterozygosity and inbreeding. Our results strengthen previous findings of limited gene flow and admixture among putative giraffe species6,7,9 and establish a genomic foundation for recognizing four species and seven subspecies, the latter of which should be considered as evolutionary significant units. Achieving a consensus over the number of species and subspecies in giraffe is essential for adequately assessing their threat level and will improve conservation efforts for these iconic taxa.


Asunto(s)
Genoma/genética , Genómica , Jirafas/clasificación , Jirafas/genética , Filogenia , Animales , Flujo Génico , Masculino , Especificidad de la Especie
9.
Evol Appl ; 13(8): 2143-2154, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32908610

RESUMEN

As we enter the sixth mass extinction, many species that are no longer self-sustaining in their natural habitat will require ex situ management. Zoos have finite resources for ex situ management, and there is a need for holistic conservation programs between the public and private sector. Ex situ populations of sable antelope, Hippotragus niger, have existed in zoos and privately owned ranches in North America since the 1910s. Unknown founder representation and relatedness has made the genetic management of this species challenging within zoos, while populations on privately owned ranches are managed independently and retain minimal-to-no pedigree history. Consequences of such challenges include an increased risk of inbreeding and a loss of genetic diversity. Here, we developed and applied a customized targeted sequence capture panel based on 5,000 genomewide single-nucleotide polymorphisms to investigate the genomic diversity present in these uniquely managed populations. We genotyped 111 sable antelope: 23 from zoos, 43 from a single conservation center, and 45 from ranches. We found significantly higher genetic diversity and significantly lower inbreeding in herds housed in zoos and conservation centers, when compared to those in privately owned ranches, likely due to genetic-based breeding recommendations implemented in the former populations. Genetic clustering was strong among all three populations, possibly as a result of genetic drift. We propose that the North American ex situ population of sable antelope would benefit from a metapopulation management system, to halt genetic drift, reduce the occurrence of inbreeding, and enable sustainable population sizes to be managed ex situ.

10.
Mol Ecol Resour ; 20(6): 1668-1681, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32365406

RESUMEN

Captive populations provide a valuable insurance against extinctions in the wild. However, they are also vulnerable to the negative impacts of inbreeding, selection and drift. Genetic information is therefore considered a critical aspect of conservation management. Recent developments in sequencing technologies have the potential to improve the outcomes of management programmes; however, the transfer of these approaches to applied conservation has been slow. The scimitar-horned oryx (Oryx dammah) is a North African antelope that has been extinct in the wild since the early 1980s and is the focus of a large-scale and long-term reintroduction project. To enable the selection of suitable founder individuals, facilitate post-release monitoring and improve captive breeding management, comprehensive genomic resources are required. Here, we used 10X Chromium sequencing together with Hi-C contact mapping to develop a chromosomal-level genome assembly for the species. The resulting assembly contained 29 chromosomes with a scaffold N50 of 100.4 Mb, and displayed strong chromosomal synteny with the cattle genome. Using resequencing data from six additional individuals, we demonstrated relatively high genetic diversity in the scimitar-horned oryx compared to other mammals, despite it having experienced a strong founding event in captivity. Additionally, the level of diversity across populations varied according to management strategy. Finally, we uncovered a dynamic demographic history that coincided with periods of climate variation during the Pleistocene. Overall, our study provides a clear example of how genomic data can uncover valuable insights into captive populations and contributes important resources to guide future management decisions of an endangered species.


Asunto(s)
Antílopes , Especies en Peligro de Extinción , Genoma , Animales , Antílopes/genética , Cromosomas , Endogamia , Sintenía
11.
Gigascience ; 9(3)2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-32112099

RESUMEN

BACKGROUND: The demographic history of any population is imprinted in the genomes of the individuals that make up the population. One of the most popular and convenient representations of genetic information is the allele frequency spectrum (AFS), the distribution of allele frequencies in populations. The joint AFS is commonly used to reconstruct the demographic history of multiple populations, and several methods based on diffusion approximation (e.g., ∂a∂i) and ordinary differential equations (e.g., moments) have been developed and applied for demographic inference. These methods provide an opportunity to simulate AFS under a variety of researcher-specified demographic models and to estimate the best model and associated parameters using likelihood-based local optimizations. However, there are no known algorithms to perform global searches of demographic models with a given AFS. RESULTS: Here, we introduce a new method that implements a global search using a genetic algorithm for the automatic and unsupervised inference of demographic history from joint AFS data. Our method is implemented in the software GADMA (Genetic Algorithm for Demographic Model Analysis, https://github.com/ctlab/GADMA). CONCLUSIONS: We demonstrate the performance of GADMA by applying it to sequence data from humans and non-model organisms and show that it is able to automatically infer a demographic model close to or even better than the one that was previously obtained manually. Moreover, GADMA is able to infer multiple demographic models at different local optima close to the global one, providing a larger set of possible scenarios to further explore demographic history.


Asunto(s)
Evolución Molecular , Frecuencia de los Genes , Población/genética , Programas Informáticos , Algoritmos , Humanos , Modelos Genéticos
12.
Genomics ; 112(1): 442-458, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-30902755

RESUMEN

The Russian Federation is the largest and one of the most ethnically diverse countries in the world, however no centralized reference database of genetic variation exists to date. Such data are crucial for medical genetics and essential for studying population history. The Genome Russia Project aims at filling this gap by performing whole genome sequencing and analysis of peoples of the Russian Federation. Here we report the characterization of genome-wide variation of 264 healthy adults, including 60 newly sequenced samples. People of Russia carry known and novel genetic variants of adaptive, clinical and functional consequence that in many cases show allele frequency divergence from neighboring populations. Population genetics analyses revealed six phylogeographic partitions among indigenous ethnicities corresponding to their geographic locales. This study presents a characterization of population-specific genomic variation in Russia with results important for medical genetics and for understanding the dynamic population history of the world's largest country.


Asunto(s)
Variación Genética , Adulto , Enfermedades Transmisibles/genética , Demografía , Haplotipos , Humanos , Mutación INDEL , Farmacogenética , Fenotipo , Filogeografía , Polimorfismo de Nucleótido Simple , Federación de Rusia/etnología , Selección Genética , Secuenciación Completa del Genoma
13.
G3 (Bethesda) ; 9(6): 1785-1793, 2019 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-31000506

RESUMEN

Genome-wide assessment of genetic diversity has the potential to increase the ability to understand admixture, inbreeding, kinship and erosion of genetic diversity affecting both captive (ex situ) and wild (in situ) populations of threatened species. The sable antelope (Hippotragus niger), native to the savannah woodlands of sub-Saharan Africa, is a species that is being managed ex situ in both public (zoo) and private (ranch) collections in the United States. Our objective was to develop whole genome sequence resources that will serve as a foundation for characterizing the genetic status of ex situ populations of sable antelope relative to populations in the wild. Here we report the draft genome assembly of a male sable antelope, a member of the subfamily Hippotraginae (Bovidae, Cetartiodactyla, Mammalia). The 2.596 Gb draft genome consists of 136,528 contigs with an N50 of 45.5 Kbp and 16,927 scaffolds with an N50 of 4.59 Mbp. De novo annotation identified 18,828 protein-coding genes and repetitive sequences encompassing 46.97% of the genome. The discovery of single nucleotide variants (SNVs) was assisted by the re-sequencing of seven additional captive and wild individuals, representing two different subspecies, leading to the identification of 1,987,710 bi-allelic SNVs. Assembly of the mitochondrial genomes revealed that each individual was defined by a unique haplotype and these data were used to infer the mitochondrial gene tree relative to other hippotragine species. The sable antelope genome constitutes a valuable resource for assessing genome-wide diversity and evolutionary potential, thereby facilitating long-term conservation of this charismatic species.


Asunto(s)
Antílopes/genética , Genoma , Genómica , Secuenciación Completa del Genoma , Animales , Antílopes/clasificación , Biodiversidad , Evolución Biológica , Biología Computacional/métodos , Femenino , Variación Genética , Genética de Población , Genoma Mitocondrial , Genómica/métodos , Masculino , Anotación de Secuencia Molecular , Fenotipo , Filogenia , Estados Unidos
14.
PLoS One ; 13(7): e0200423, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29995946

RESUMEN

A comparative analysis of whole genome sequencing (WGS) and genotype calling was initiated for ten human genome samples sequenced by St. Petersburg State University Peterhof Sequencing Center and by three commercial sequencing centers outside of Russia. The sequence quality, efficiency of DNA variant and genotype calling were compared with each other and with DNA microarrays for each of ten study subjects. We assessed calling of SNPs, indels, copy number variation, and the speed of WGS throughput promised. Twenty separate QC analyses showed high similarities among the sequence quality and called genotypes. The ten genomes tested by the centers included eight American patients afflicted with autoimmune hepatitis (AIH), plus one case's unaffected parents, in a prelude to discovering genetic influences in this rare disease of unknown etiology. The detailed internal replication and parallel analyses allowed the observation of two of eight AIH cases carrying a rare allele genotype for a previously described AIH-associated gene (FTCD), plus multiple occurrences of known HLA-DRB1 alleles associated with AIH (HLA-DRB1-03:01:01, 13:01:01 and 7:01:01). We also list putative SNVs in other genes as suggestive in AIH influence.


Asunto(s)
Técnicas de Genotipaje , Hepatitis Autoinmune/genética , Secuenciación Completa del Genoma , Adolescente , Amoníaco-Liasas/genética , Niño , Preescolar , Estudios de Cohortes , Variaciones en el Número de Copia de ADN , Femenino , Predisposición Genética a la Enfermedad , Glutamato Formimidoiltransferasa/genética , Cadenas HLA-DRB1/genética , Humanos , Mutación INDEL , Masculino , Enzimas Multifuncionales , Análisis de Secuencia por Matrices de Oligonucleótidos , Polimorfismo de Nucleótido Simple , Control de Calidad , Federación de Rusia , Factores de Tiempo
15.
Gigascience ; 7(6)2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29718205

RESUMEN

Solenodons are insectivores that live in Hispaniola and Cuba. They form an isolated branch in the tree of placental mammals that are highly divergent from other eulipothyplan insectivores The history, unique biology, and adaptations of these enigmatic venomous species could be illuminated by the availability of genome data. However, a whole genome assembly for solenodons has not been previously performed, partially due to the difficulty in obtaining samples from the field. Island isolation and reduced numbers have likely resulted in high homozygosity within the Hispaniolan solenodon (Solenodon paradoxus). Thus, we tested the performance of several assembly strategies on the genome of this genetically impoverished species. The string graph-based assembly strategy seemed a better choice compared to the conventional de Bruijn graph approach due to the high levels of homozygosity, which is often a hallmark of endemic or endangered species. A consensus reference genome was assembled from sequences of 5 individuals from the southern subspecies (S. p. woodi). In addition, we obtained an additional sequence from 1 sample of the northern subspecies (S. p. paradoxus). The resulting genome assemblies were compared to each other and annotated for genes, with an emphasis on venom genes, repeats, variable microsatellite loci, and other genomic variants. Phylogenetic positioning and selection signatures were inferred based on 4,416 single-copy orthologs from 10 other mammals. We estimated that solenodons diverged from other extant mammals 73.6 million years ago. Patterns of single-nucleotide polymorphism variation allowed us to infer population demography, which supported a subspecies split within the Hispaniolan solenodon at least 300 thousand years ago.


Asunto(s)
Evolución Biológica , Secuencia Conservada/genética , Especies en Peligro de Extinción , Islas , Mamíferos/genética , Análisis de Secuencia de ADN/métodos , Animales , Cuba , Genoma , Heterocigoto , Especificidad de la Especie
16.
Curr Biol ; 28(1): R13-R14, 2018 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-29316411

RESUMEN

Black and white rhinoceros (Diceros bicornis and Ceratotherium simum) are iconic African species that are classified by the International Union for the Conservation of Nature (IUCN) as Critically Endangered and Near Threatened (http://www.iucnredlist.org/), respectively [1]. At the end of the 19th century, Southern white rhinoceros (Ceratotherium simum simum) numbers had declined to fewer than 50 animals in the Hluhluwe-iMfolozi region of the KwaZulu-Natal (KZN) province of South Africa, mainly due to uncontrolled hunting [2,3]. Efforts by the Natal Parks Board facilitated an increase in population to over 20,000 in 2015 through aggressive conservation management [2]. Black rhinoceros (Diceros bicornis) populations declined from several hundred thousand in the early 19th century to ∼65,000 in 1970 and to ∼2,400 by 1995 [1] with subsequent genetic reduction, also due to hunting, land clearances and later poaching [4]. In South Africa, rhinoceros poaching incidents have increased from 13 in 2007 to 1,215 in 2014 [1]. This has occurred despite strict trade bans on rhinoceros products and strict enforcement in recent years.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Ciencias Forenses/métodos , Repeticiones de Microsatélite , Perisodáctilos , África , Animales , Cuernos/anatomía & histología , Perisodáctilos/anatomía & histología , Perisodáctilos/genética
17.
BMC Res Notes ; 11(1): 18, 2018 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-29329601

RESUMEN

OBJECTIVE: Nicotiana glauca (tree tobacco) is a naturally transgenic plant, containing sequences acquired from Agrobacterium rhizogenes by horizontal gene transfer. Besides, N. glauca contains a wide profile of alkaloids of medical interest. DATA DESCRIPTION: We report a high-depth sequencing and de novo assembly of N. glauca full genome and analysis of genome elements with bacterial origin. The draft genome assembly is 3.2 Gb, with N50 size of 31.1 kbp. Comparative analysis confirmed the presence of single, previously described gT insertion. No evidence was acquired to support idea of multiple T-DNA insertions in the N. glauca genome. Our data is the first comprehensive de novo assembly of tree tobacco and provide valuable information for researches in pharmacological and in phylogenetic fields.


Asunto(s)
ADN Bacteriano/genética , Transferencia de Gen Horizontal/genética , Genoma de Planta/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Nicotiana/genética , Análisis de Secuencia de ADN/métodos
18.
Neurotoxicol Teratol ; 66: 125-131, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29247702

RESUMEN

Epigenetic regulation plays an important role in development, at the embryonic stages and later during the lifespan. Some epigenetic marks are highly conserved throughout the lifespan whereas others are closely associated with specific age periods and/or particular environmental factors. Little is known about the dynamics of epigenetic regulation during childhood, especially during the period of rapid early development. Our study was aimed to determine whether the developmental program at the early stages of human development is accompanied by significant changes in the systems of genome regulation, specifically, by genome-wide changes in DNA methylation. Using a sequencing approach (MBD-seq) we investigated genome-wide DNA methylation patterns in the T-lymphocytes of three healthy toddlers at two timepoints within the second year of life. Pairwise comparison of the methylation patterns across the individuals and time points was conducted to determine common longitudinal changes in the DNA methylation patterns. Despite relatively high interindividual variability in their epigenetic profiles and the dynamics of these profiles during the second year of life, all children showed consistent changes in the DNA methylation patterns of genes involved in the control of the immune system and genes related to the development of the CNS. Thereby, we provide evidence that early development might be accompanied by epigenetic changes in specific functional groups of genes; many such epigenetic changes appear to be related to the rapid development of the CNS.


Asunto(s)
Desarrollo Infantil , Metilación de ADN/genética , Epigénesis Genética , Linfocitos T/metabolismo , Preescolar , Humanos , Lactante , Estudios Longitudinales , Masculino
19.
J Hered ; 108(6): 671-677, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28821181

RESUMEN

The dwindling wildlife species of our planet have become a cause célèbre for conservation groups, governments, and concerned citizens throughout the world. The application of powerful new genetic technologies to surviving populations of threatened mammals has revolutionized our ability to recognize hidden perils that afflict them. We have learned new lessons of survival, adaptation, and evolution from viewing the natural history of genomes in hundreds of detailed studies. A single case history of one species, the African cheetah, Acinonyx jubatus, is here reviewed to reveal a long-term story of conservation challenges and action informed by genetic discoveries and insights. A synthesis of 3 decades of data, interpretation, and controversy, capped by whole genome sequence analysis of cheetahs, provides a compelling tale of conservation relevance and action to protect this species and other threatened wildlife.


Asunto(s)
Acinonyx/genética , Conservación de los Recursos Naturales , Variación Genética , Genética de Población , Animales , Animales Salvajes/genética , Genoma
20.
Mitochondrial DNA A DNA Mapp Seq Anal ; 28(5): 662-670, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-27159724

RESUMEN

Solenodons are insectivores found only in Hispaniola and Cuba, with a Mesozoic divergence date versus extant mainland mammals. Solenodons are the oldest lineage of living eutherian mammal for which a mitogenome sequence has not been reported. We determined complete mitogenome sequences for six Hispaniolan solenodons (Solenodon paradoxus) using next-generation sequencing. The solenodon mitogenomes were 16,454-16,457 bp long and carried the expected repertoire of genes. A mitogenomic phylogeny confirmed the basal position of solenodons relative to shrews and moles, with solenodon mitogenomes estimated to have diverged from those of other mammals ca. 78 Mya. Control region sequences of solenodons from the northern (n = 3) and southern (n = 5) Dominican Republic grouped separately in a network, with FST = 0.72 (p = 0.036) between north and south. This regional genetic divergence supports previous morphological and genetic reports recognizing northern (S. p. paradoxus) and southern (S. p. woodi) subspecies in need of separate conservation plans.


Asunto(s)
Eulipotyphla/clasificación , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Mitocondrias/genética , Análisis de Secuencia de ADN/métodos , Animales , Eulipotyphla/genética , Evolución Molecular , Tamaño del Genoma , Genoma Mitocondrial , Filogenia
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