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1.
Mol Ecol ; 27(18): 3599-3612, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30074659

RESUMEN

Allee effects reduce the viability of small populations in many different ways, which act synergistically to lead populations towards extinction vortexes. The Sierra Morena wolf population, isolated in the south of the Iberian Peninsula and composed of just one or few packs for decades, represents a good example of how diverse threats act additively in very small populations. We sequenced the genome of one of the last wolves identified (and road-killed) in Sierra Morena and that of another wolf in the Iberian Wolf Captive Breeding Program and compared them with other wolf and dog genomes from around the world (including two previously published genome sequences from northern Iberian wolves). The results showed relatively low overall genetic diversity in Iberian wolves, but diverse population histories including past introgression of dog genes. The Sierra Morena wolf had an extraordinarily high level of inbreeding and long runs of homozygosity, resulting from the long isolation. In addition, about one-third of the genome was of dog origin. Despite the introgression of dog genes, heterozygosity remained low because of continued inbreeding after several hybridization events. The results thus illustrate the case of a small and isolated wolf population where the low population density may have favoured hybridization and introgression of dog alleles, but continued inbreeding may have resulted in large chromosomal fragments of wolf origin completely disappearing from the population, and being replaced by chromosomal fragments of dog origin. The latest population surveys suggest that this population may have gone extinct.


Asunto(s)
Genética de Población , Endogamia , Lobos/genética , Alelos , Animales , Mapeo Cromosómico , Conservación de los Recursos Naturales , Perros , Heterocigoto , Hibridación Genética , Polimorfismo de Nucleótido Simple , Densidad de Población , España , Secuenciación Completa del Genoma
2.
BMC Genomics ; 18(1): 977, 2017 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-29258433

RESUMEN

BACKGROUND: Whole genome re-sequencing data from dogs and wolves are now commonly used to study how natural and artificial selection have shaped the patterns of genetic diversity. Single nucleotide polymorphisms, microsatellites and variants in mitochondrial DNA have been interrogated for links to specific phenotypes or signals of domestication. However, copy number variation (CNV), despite its increasingly recognized importance as a contributor to phenotypic diversity, has not been extensively explored in canids. RESULTS: Here, we develop a new accurate probabilistic framework to create fine-scale genomic maps of segmental duplications (SDs), compare patterns of CNV across groups and investigate their role in the evolution of the domestic dog by using information from 34 canine genomes. Our analyses show that duplicated regions are enriched in genes and hence likely possess functional importance. We identify 86 loci with large CNV differences between dogs and wolves, enriched in genes responsible for sensory perception, immune response, metabolic processes, etc. In striking contrast to the observed loss of nucleotide diversity in domestic dogs following the population bottlenecks that occurred during domestication and breed creation, we find a similar proportion of CNV loci in dogs and wolves, suggesting that other dynamics are acting to particularly select for CNVs with potentially functional impacts. CONCLUSIONS: This work is the first comparison of genome wide CNV patterns in domestic and wild canids using whole-genome sequencing data and our findings contribute to study the impact of novel kinds of genetic changes on the evolution of the domestic dog.


Asunto(s)
Variaciones en el Número de Copia de ADN , Perros/genética , Lobos/genética , Animales , Cruzamiento , Genómica , Duplicaciones Segmentarias en el Genoma , Análisis de Secuencia de ADN
3.
Mol Biol Evol ; 33(10): 2759-64, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27486221

RESUMEN

The evolutionary dynamics of transposable elements (TEs) are still poorly understood. One reason is that TE abundance needs to be studied at the population level, but sequencing individuals on a population scale is still too expensive to characterize TE abundance in multiple populations. Although sequencing pools of individuals dramatically reduces sequencing costs, a comparison of TE abundance between pooled samples has been difficult, if not impossible, due to various biases. Here, we introduce a novel bioinformatic tool, PoPoolationTE2, which is specifically tailored for the comparison of TE abundance among pooled population samples or different tissues. Using computer simulations, we demonstrate that PoPoolationTE2 not only faithfully recovers TE insertion frequencies and positions but, by homogenizing the power to identify TEs across samples, it provides an unbiased comparison of TE abundance between pooled population samples. We anticipate that PoPoolationTE2 will greatly facilitate the analysis of TE insertion patterns in a broad range of applications.


Asunto(s)
Elementos Transponibles de ADN , Genómica/métodos , Metagenómica/métodos , Análisis de Secuencia de ADN/métodos , Animales , Biología Computacional/métodos , Drosophila melanogaster , Evolución Molecular , Modelos Genéticos , Selección Genética/genética
4.
Nano Lett ; 15(2): 1117-21, 2015 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-25603117

RESUMEN

This work provides experimental evidence and theoretical explanations regarding the formation mechanisms of GaN nanowires grown by selective area growth on GaN-on-sapphire templates. The first growth stage, driven by selective area growth kinetics, consists of initial nucleation (along the nanohole inner periphery), coalescence onset and full coalescence, producing a single nanocrystal within each nanohole. In the second growth stage, driven by free-surface-energy minimization, the formed nanocrystal undergoes morphological evolution, exhibiting initial cylindrical-like shape, intermediate dodecagonal shape and a final, thermodynamically stable hexagonal shape. From this point on, the nanowire vertical growth proceeds while keeping the stable hexagonal form.

5.
Arch Argent Pediatr ; 117(1): e34-e36, 2019 02 01.
Artículo en Español | MEDLINE | ID: mdl-30652452

RESUMEN

Migraine with aura in children is often reported, typical aura without headache is reported sometimes, but persistent aura and Alice in Wonderland syndrome is exceptionally reported. We present a case corresponding to the last one mentioned in a 6-year-old patient who had at least two episodes with the typical characteristics of aura without migraine before developing more frequently the complete clinical picture of aura and subsequently headache. The complementary studies systematically done to the patient were normal and she improved with conventional therapy.It is important to emphasize that the syndrome should be suspected in any patient who presents the described manifestations in order to approach to the diagnosis of aura without migraine, to discard either organic pathology or another cause and to indicate adequate therapeutic measures.


La migraña con aura en pacientes pediátricos es reportada con frecuencia; el aura típica sin migraña, en raras ocasiones, y el aura persistente asociada al denominado síndrome de Alicia en el País de las Maravillas, excepcionalmente.El objetivo de este reporte es presentar un caso clínico correspondiente a la última variedad mencionada. Se trata de una paciente de 6 años de edad, quien tuvo, al menos, dos episodios con estas características antes de presentar un cuadro clínico completo de aura y, consecutivamente, cefalea con más frecuencia. Los estudios complementarios practicados de manera sistemática a la paciente fueron normales, con mejoría clínica con el tratamiento convencional.Se debe sospechar el síndrome en todo paciente que se presente con las características descritas a fin de aproximarse al diagnóstico de aura sin migraña, descartar patologías orgánicas o de otra naturaleza e instaurar la terapéutica adecuada.


Asunto(s)
Síndrome de Alicia en el País de las Maravillas/diagnóstico , Niño , Femenino , Humanos
6.
Mol Ecol Resour ; 18(3): 676-680, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29171165

RESUMEN

Sequencing whole genomes has become a standard research tool in many disciplines including Molecular Ecology, but the rapid technological advances in combination with several competing platforms have resulted in a confusing diversity of formats. This lack of standard formats causes several problems, such as undocumented preprocessing steps or the loss of information in downstream software tools, which do not account for the specifics of the different available formats. ReadTools is an open-source Java toolkit designed to standardize and preprocess read data from different platforms. It manages FASTQ- and SAM-formatted inputs while dealing with platform-specific peculiarities and provides a standard SAM compliant output. The code and executable are available at https://github.com/magicDGS/ReadTools.


Asunto(s)
Análisis de Secuencia/métodos , Programas Informáticos , Biología Computacional , Internet , Análisis de Secuencia de ADN
7.
Arch. venez. pueric. pediatr ; 85(1): 16-19, abr. 2022. tab
Artículo en Español | LILACS, LIVECS | ID: biblio-1572647

RESUMEN

El síndrome de münchausen por poderes constituye una particular forma de maltrato infantil cuya gravedad radica en su potencialmente elevada morbi-mortalidad, en gran parte debida a su difícil diagnóstico y manejo. se reporta la experiencia de dos casos de este síndrome de características extraordinariamente similares, y con cuadros clínicos extremos dada la diversidad de manifestaciones narradas, el número de diagnósticos, la gran cantidad de consultas y el elevado número de ingresos; todo ello denota la dificultad en el diagnóstico y manejo de esta patología, cuyo retraso implica un gran peligro para el niño a nivel psicológico, físico y social. en ambos casos el agente causal es la madre, con un nivel socioeconómico bajo e importante disfunción familiar(AU)


Münchausen syndrome by proxy is a particular form of child abuse whose severity lies in its high morbidity and mortality, due to its difficult diagnosis and management. we provide the experience of two suggestive cases of this syndrome with extraordinarily similar characteristics and with extreme clinical presentations due to the variety of manifestations, the elevated number of diagnosis, consultations and admissions to the hospital. the aim of this presentation is to highlight the difficulty in the diagnosis and management of this pathology, whose delay implies a great danger for the child at a psychological, physical and social level. In both cases the causal agent is the mother, with a low socioeconomic level and significant family dysfunction(AU)


Asunto(s)
Humanos , Masculino , Niño , Maltrato a los Niños , Síndrome de Munchausen Causado por Tercero , Síndrome de Munchausen , Indicadores de Morbimortalidad , Trastornos Mentales
8.
Arch. argent. pediatr ; 117(1): 34-36, feb. 2019.
Artículo en Español | LILACS, BINACIS | ID: biblio-983776

RESUMEN

La migraña con aura en pacientes pediátricos es reportada con frecuencia; el aura típica sin migraña, en raras ocasiones, y el aura persistente asociada al denominado síndrome de Alicia en el País de las Maravillas, excepcionalmente. El objetivo de este reporte es presentar un caso clínico correspondiente a la última variedad mencionada. Se trata de una paciente de 6 años de edad, quien tuvo, al menos, dos episodios con estas características antes de presentar un cuadro clínico completo de aura y, consecutivamente, cefalea con más frecuencia. Los estudios complementarios practicados de manera sistemática a la paciente fueron normales, con mejoría clínica con el tratamiento convencional. Se debe sospechar el síndrome en todo paciente que se presente con las características descritas a fin de aproximarse al diagnóstico de aura sin migraña, descartar patologías orgánicas o de otra naturaleza e instaurar la terapéutica adecuada.


Migraine with aura in children is often reported, typical aura without headache is reported sometimes, but persistent aura and Alice in Wonderland syndrome is exceptionally reported. We present a case corresponding to the last one mentioned in a 6-year-old patient who had at least two episodes with the typical characteristics of aura without migraine before developing more frequently the complete clinical picture of aura and subsequently headache. The complementary studies systematically done to the patient were normal and she improved with conventional therapy. It is important to emphasize that the syndrome should be suspected in any patient who presents the described manifestations in order to approach to the diagnosis of aura without migraine, to discard either organic pathology or another cause and to indicate adequate therapeutic measures.


Asunto(s)
Humanos , Femenino , Niño , Niño , Migraña con Aura , Síndrome de Alicia en el País de las Maravillas
9.
PLoS One ; 9(8): e105105, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25116044

RESUMEN

Previous mitochondrial DNA analyses on ancient European remains have suggested that the current distribution of haplogroup H was modeled by the expansion of the Bell Beaker culture (ca 4,500-4,050 years BP) out of Iberia during the Chalcolithic period. However, little is known on the genetic composition of contemporaneous Iberian populations that do not carry the archaeological tool kit defining this culture. Here we have retrieved mitochondrial DNA (mtDNA) sequences from 19 individuals from a Chalcolithic sample from El Mirador cave in Spain, dated to 4,760-4,200 years BP and we have analyzed the haplogroup composition in the context of modern and ancient populations. Regarding extant African, Asian and European populations, El Mirador shows affinities with Near Eastern groups. In different analyses with other ancient samples, El Mirador clusters with Middle and Late Neolithic populations from Germany, belonging to the Rössen, the Salzmünde and the Baalberge archaeological cultures but not with contemporaneous Bell Beakers. Our analyses support the existence of a common genetic signal between Western and Central Europe during the Middle and Late Neolithic and points to a heterogeneous genetic landscape among Chalcolithic groups.


Asunto(s)
ADN Mitocondrial/historia , Etnicidad/historia , Cuevas , ADN Mitocondrial/genética , ADN Mitocondrial/aislamiento & purificación , Etnicidad/genética , Europa (Continente) , Evolución Molecular , Genética de Población , Haplotipos , Historia Antigua , Humanos , Análisis de Componente Principal , España
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