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1.
Clin Med Insights Case Rep ; 16: 11795476231159584, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37033677

RESUMEN

Background: It has been proposed that the immunomodulatory capacity of neuraltherapeutic medicine (NTM) functions by means of stimuli to the nervous system, which influences the self-regulatory and plastic capacity of the nervous system, especially through the autonomic balance between the sympathetic and parasympathetic nervous systems. Several studies report the usefulness of NTM in inflammatory pathologies. Case presentation: A case report through a retrospective review of the medical history of an 82-year-old male patient with a diagnosis of acute SARS-CoV-2 who received a therapeutic intervention of NTM at the beginning of his hospitalization and presented satisfactory clinical evolution, with a follow-up for 18 months without post-COVID sequelae. A patient diagnosed with acute pneumonia for SARS-CoV-2, and mild ARDS, with markers of severity given by the history of COPD, advanced age, and elevation of LDH, ferritin, and CRP. On the third day of hospitalization, he presented an episode of pulmonary thromboembolism. He presented significant clinical improvement with in-hospital management for 9 days and underwent out-patient control with no post-COVID sequelae. Conclusions: NTM could be useful for the management of acute inflammatory diseases, including viral diseases such as SARS-CoV-2, in a mild or severe state of inflammation, when added to allopathic medicine, and it can improve clinical evolution and long-term sequelae. More studies are needed to validate this information.

2.
Rev. cuba. med. mil ; 52(1)mar. 2023.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1521979

RESUMEN

Introducción: La musicoterapia puede ser utilizada para influenciar en el estado físico y emocional de pacientes diagnosticados con la COVID-19. Se realiza una revisión sistemática exploratoria que incluye estudios observacionales y ensayos clínicos; Pubmed y Scopus fueron las bases de datos empleadas para la realización de la búsqueda. Además, se incluyen registros de ensayos clínicos de la Plataforma de Registros Internacionales de Ensayos Clínicos de la Organización Mundial de la Salud. Objetivo: Explorar la literatura médica disponible, sobre el impacto clínico de la musicoterapia en pacientes diagnosticados con la COVID-19. Desarrollo: De 39 documentos encontrados se incluyen 2 artículos: un ensayo clínico y un reporte de caso, con una población total de 41 pacientes. Se encuentra evidencia médica que respalda el impacto clínico favorable sobre la saturación de oxígeno, rehabilitación física y síntomas asociados al estrés en pacientes con diagnóstico de la COVID-19 con y sin requerimiento de soporte ventilatorio. Conclusiones: La musicoterapia es una herramienta útil en el tratamiento y rehabilitación no farmacológica de pacientes con la COVID-19; sin embargo, son necesarios nuevos estudios clínicos con mayor número de poblaciones muestrales y mayor tiempo de seguimiento.


Background: Music therapy can be used to influence the physical and emotional state of patients diagnosed with COVID-19. An exploratory systematic review was carried out including observational studies and clinical trials, Pubmed and Scopus were the databases used to carry out the literature search. In addition, clinical trial registries from the World Health Organization International Clinical Trials Registry Platform are included. Objective: To explore the available medical literature on the clinical impact of music therapy in patients diagnosed with COVID-19. Development: Of 39 documents found in the search, two articles are included: a clinical trial and a case report, with a total population of 41 patients. Medical evidence is found to support the favorable clinical impact on oxygen saturation, physical rehabilitation and symptoms associated with stress in patients diagnosed with COVID-19 with and without the need for ventilatory support. Conclusions: Music therapy is a useful tool in the non-pharmacological treatment and rehabilitation of patients with COVID-19. However, new clinical studies with a larger number of sample populations and follow-up times using music therapy in this disease are necessary.

3.
Science ; 377(6601): 72-79, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35771911

RESUMEN

Micronesia began to be peopled earlier than other parts of Remote Oceania, but the origins of its inhabitants remain unclear. We generated genome-wide data from 164 ancient and 112 modern individuals. Analysis reveals five migratory streams into Micronesia. Three are East Asian related, one is Polynesian, and a fifth is a Papuan source related to mainland New Guineans that is different from the New Britain-related Papuan source for southwest Pacific populations but is similarly derived from male migrants ~2500 to 2000 years ago. People of the Mariana Archipelago may derive all of their precolonial ancestry from East Asian sources, making them the only Remote Oceanians without Papuan ancestry. Female-inherited mitochondrial DNA was highly differentiated across early Remote Oceanian communities but homogeneous within, implying matrilocal practices whereby women almost never raised their children in communities different from the ones in which they grew up.


Asunto(s)
ADN Antiguo , ADN Mitocondrial , Migración Humana , Pueblo Asiatico/genética , Niño , ADN Mitocondrial/genética , Femenino , Historia Antigua , Migración Humana/historia , Humanos , Masculino , Micronesia , Oceanía
4.
Proc Natl Acad Sci U S A ; 115(26): 6774-6779, 2018 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-29895688

RESUMEN

The extent to which prehistoric migrations of farmers influenced the genetic pool of western North Africans remains unclear. Archaeological evidence suggests that the Neolithization process may have happened through the adoption of innovations by local Epipaleolithic communities or by demic diffusion from the Eastern Mediterranean shores or Iberia. Here, we present an analysis of individuals' genome sequences from Early and Late Neolithic sites in Morocco and from Early Neolithic individuals from southern Iberia. We show that Early Neolithic Moroccans (∼5,000 BCE) are similar to Later Stone Age individuals from the same region and possess an endemic element retained in present-day Maghrebi populations, confirming a long-term genetic continuity in the region. This scenario is consistent with Early Neolithic traditions in North Africa deriving from Epipaleolithic communities that adopted certain agricultural techniques from neighboring populations. Among Eurasian ancient populations, Early Neolithic Moroccans are distantly related to Levantine Natufian hunter-gatherers (∼9,000 BCE) and Pre-Pottery Neolithic farmers (∼6,500 BCE). Late Neolithic (∼3,000 BCE) Moroccans, in contrast, share an Iberian component, supporting theories of trans-Gibraltar gene flow and indicating that Neolithization of North Africa involved both the movement of ideas and people. Lastly, the southern Iberian Early Neolithic samples share the same genetic composition as the Cardial Mediterranean Neolithic culture that reached Iberia ∼5,500 BCE. The cultural and genetic similarities between Iberian and North African Neolithic traditions further reinforce the model of an Iberian migration into the Maghreb.


Asunto(s)
Etnicidad/genética , Genoma Humano , Migración Humana/historia , África del Norte , Agricultura/historia , Cromosomas Humanos Y/genética , ADN Mitocondrial/genética , Etnicidad/historia , Europa (Continente) , Flujo Génico , Biblioteca de Genes , Genética de Población , Historia Antigua , Humanos , Medio Oriente , Marruecos , Análisis de Secuencia de ADN , España/etnología
5.
Lancet Oncol ; 19(6): 785-798, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29753700

RESUMEN

BACKGROUND: Medulloblastoma is associated with rare hereditary cancer predisposition syndromes; however, consensus medulloblastoma predisposition genes have not been defined and screening guidelines for genetic counselling and testing for paediatric patients are not available. We aimed to assess and define these genes to provide evidence for future screening guidelines. METHODS: In this international, multicentre study, we analysed patients with medulloblastoma from retrospective cohorts (International Cancer Genome Consortium [ICGC] PedBrain, Medulloblastoma Advanced Genomics International Consortium [MAGIC], and the CEFALO series) and from prospective cohorts from four clinical studies (SJMB03, SJMB12, SJYC07, and I-HIT-MED). Whole-genome sequences and exome sequences from blood and tumour samples were analysed for rare damaging germline mutations in cancer predisposition genes. DNA methylation profiling was done to determine consensus molecular subgroups: WNT (MBWNT), SHH (MBSHH), group 3 (MBGroup3), and group 4 (MBGroup4). Medulloblastoma predisposition genes were predicted on the basis of rare variant burden tests against controls without a cancer diagnosis from the Exome Aggregation Consortium (ExAC). Previously defined somatic mutational signatures were used to further classify medulloblastoma genomes into two groups, a clock-like group (signatures 1 and 5) and a homologous recombination repair deficiency-like group (signatures 3 and 8), and chromothripsis was investigated using previously established criteria. Progression-free survival and overall survival were modelled for patients with a genetic predisposition to medulloblastoma. FINDINGS: We included a total of 1022 patients with medulloblastoma from the retrospective cohorts (n=673) and the four prospective studies (n=349), from whom blood samples (n=1022) and tumour samples (n=800) were analysed for germline mutations in 110 cancer predisposition genes. In our rare variant burden analysis, we compared these against 53 105 sequenced controls from ExAC and identified APC, BRCA2, PALB2, PTCH1, SUFU, and TP53 as consensus medulloblastoma predisposition genes according to our rare variant burden analysis and estimated that germline mutations accounted for 6% of medulloblastoma diagnoses in the retrospective cohort. The prevalence of genetic predispositions differed between molecular subgroups in the retrospective cohort and was highest for patients in the MBSHH subgroup (20% in the retrospective cohort). These estimates were replicated in the prospective clinical cohort (germline mutations accounted for 5% of medulloblastoma diagnoses, with the highest prevalence [14%] in the MBSHH subgroup). Patients with germline APC mutations developed MBWNT and accounted for most (five [71%] of seven) cases of MBWNT that had no somatic CTNNB1 exon 3 mutations. Patients with germline mutations in SUFU and PTCH1 mostly developed infant MBSHH. Germline TP53 mutations presented only in childhood patients in the MBSHH subgroup and explained more than half (eight [57%] of 14) of all chromothripsis events in this subgroup. Germline mutations in PALB2 and BRCA2 were observed across the MBSHH, MBGroup3, and MBGroup4 molecular subgroups and were associated with mutational signatures typical of homologous recombination repair deficiency. In patients with a genetic predisposition to medulloblastoma, 5-year progression-free survival was 52% (95% CI 40-69) and 5-year overall survival was 65% (95% CI 52-81); these survival estimates differed significantly across patients with germline mutations in different medulloblastoma predisposition genes. INTERPRETATION: Genetic counselling and testing should be used as a standard-of-care procedure in patients with MBWNT and MBSHH because these patients have the highest prevalence of damaging germline mutations in known cancer predisposition genes. We propose criteria for routine genetic screening for patients with medulloblastoma based on clinical and molecular tumour characteristics. FUNDING: German Cancer Aid; German Federal Ministry of Education and Research; German Childhood Cancer Foundation (Deutsche Kinderkrebsstiftung); European Research Council; National Institutes of Health; Canadian Institutes for Health Research; German Cancer Research Center; St Jude Comprehensive Cancer Center; American Lebanese Syrian Associated Charities; Swiss National Science Foundation; European Molecular Biology Organization; Cancer Research UK; Hertie Foundation; Alexander and Margaret Stewart Trust; V Foundation for Cancer Research; Sontag Foundation; Musicians Against Childhood Cancer; BC Cancer Foundation; Swedish Council for Health, Working Life and Welfare; Swedish Research Council; Swedish Cancer Society; the Swedish Radiation Protection Authority; Danish Strategic Research Council; Swiss Federal Office of Public Health; Swiss Research Foundation on Mobile Communication; Masaryk University; Ministry of Health of the Czech Republic; Research Council of Norway; Genome Canada; Genome BC; Terry Fox Research Institute; Ontario Institute for Cancer Research; Pediatric Oncology Group of Ontario; The Family of Kathleen Lorette and the Clark H Smith Brain Tumour Centre; Montreal Children's Hospital Foundation; The Hospital for Sick Children: Sonia and Arthur Labatt Brain Tumour Research Centre, Chief of Research Fund, Cancer Genetics Program, Garron Family Cancer Centre, MDT's Garron Family Endowment; BC Childhood Cancer Parents Association; Cure Search Foundation; Pediatric Brain Tumor Foundation; Brainchild; and the Government of Ontario.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Cerebelosas/genética , Metilación de ADN , Pruebas Genéticas/métodos , Mutación de Línea Germinal , Meduloblastoma/genética , Modelos Genéticos , Adolescente , Adulto , Neoplasias Cerebelosas/mortalidad , Neoplasias Cerebelosas/patología , Neoplasias Cerebelosas/terapia , Niño , Preescolar , Análisis Mutacional de ADN , Femenino , Perfilación de la Expresión Génica , Predisposición Genética a la Enfermedad , Herencia , Humanos , Lactante , Masculino , Meduloblastoma/mortalidad , Meduloblastoma/patología , Meduloblastoma/terapia , Linaje , Fenotipo , Valor Predictivo de las Pruebas , Supervivencia sin Progresión , Estudios Prospectivos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Factores de Riesgo , Transcriptoma , Secuenciación del Exoma , Adulto Joven
6.
Proc Natl Acad Sci U S A ; 115(17): E4006-E4012, 2018 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-29632188

RESUMEN

Patagonia was the last region of the Americas reached by humans who entered the continent from Siberia ∼15,000-20,000 y ago. Despite recent genomic approaches to reconstruct the continental evolutionary history, regional characterization of ancient and modern genomes remains understudied. Exploring the genomic diversity within Patagonia is not just a valuable strategy to gain a better understanding of the history and diversification of human populations in the southernmost tip of the Americas, but it would also improve the representation of Native American diversity in global databases of human variation. Here, we present genome data from four modern populations from Central Southern Chile and Patagonia (n = 61) and four ancient maritime individuals from Patagonia (∼1,000 y old). Both the modern and ancient individuals studied in this work have a greater genetic affinity with other modern Native Americans than to any non-American population, showing within South America a clear structure between major geographical regions. Native Patagonian Kawéskar and Yámana showed the highest genetic affinity with the ancient individuals, indicating genetic continuity in the region during the past 1,000 y before present, together with an important agreement between the ethnic affiliation and historical distribution of both groups. Lastly, the ancient maritime individuals were genetically equidistant to a ∼200-y-old terrestrial hunter-gatherer from Tierra del Fuego, which supports a model with an initial separation of a common ancestral group to both maritime populations from a terrestrial population, with a later diversification of the maritime groups.


Asunto(s)
Variación Genética , Genoma Humano , Indígenas Sudamericanos/genética , Chile , Femenino , Historia Antigua , Humanos , Indígenas Sudamericanos/historia , Masculino
7.
Proc Natl Acad Sci U S A ; 115(10): 2341-2346, 2018 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-29463742

RESUMEN

The Caribbean was one of the last parts of the Americas to be settled by humans, but how and when the islands were first occupied remains a matter of debate. Ancient DNA can help answering these questions, but the work has been hampered by poor DNA preservation. We report the genome sequence of a 1,000-year-old Lucayan Taino individual recovered from the site of Preacher's Cave in the Bahamas. We sequenced her genome to 12.4-fold coverage and show that she is genetically most closely related to present-day Arawakan speakers from northern South America, suggesting that the ancestors of the Lucayans originated there. Further, we find no evidence for recent inbreeding or isolation in the ancient genome, suggesting that the Lucayans had a relatively large effective population size. Finally, we show that the native American components in some present-day Caribbean genomes are closely related to the ancient Taino, demonstrating an element of continuity between precontact populations and present-day Latino populations in the Caribbean.


Asunto(s)
Indio Americano o Nativo de Alaska/genética , Genoma Humano/genética , Migración Humana/estadística & datos numéricos , Adulto , Arqueología , Bahamas , ADN Antiguo , ADN Mitocondrial/genética , Femenino , Genética de Población , Genómica , Hispánicos o Latinos/genética , Historia Antigua , Migración Humana/historia , Humanos , Masculino , Paleontología , Filogenia , Adulto Joven
8.
J Hand Ther ; 29(4): 507-514, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27665394

RESUMEN

Functional electrical stimulation (FES) has shown to improve motor function of the affected side in stroke patients; however, the effects of FES on proprioception, the functional recovery of the paretic upper limb, and the patient quality of life (QoL) are not clear. The aim of the current case report was to determine whether FES can improve joint position sense and the scores on measurements of upper limb function and a QoL survey. The participant was assessed before and after 10 consecutive intervention sessions; in addition, the patient performed the training tasks in the workstation assisted by the FES device. Improvements in angles and time only in the affected wrist and enhancement in the Action Research Arm Test scores for both upper limbs were found after FES intervention. In addition, the patient's health-related QoL measurements improved. FES could ameliorate the proprioceptive deficit and the activity limitations of a stroke survivor. OXFORD LEVEL OF EVIDENCE: 3b; individual case control study.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Paresia/rehabilitación , Calidad de Vida , Accidente Cerebrovascular/complicaciones , Extremidad Superior/fisiopatología , Evaluación de la Discapacidad , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Destreza Motora/fisiología , Paresia/etiología , Paresia/psicología , Propiocepción/fisiología , Recuperación de la Función/fisiología , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/psicología , Rehabilitación de Accidente Cerebrovascular/métodos , Análisis y Desempeño de Tareas , Resultado del Tratamiento
9.
Nature ; 506(7487): 225-9, 2014 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-24522598

RESUMEN

Clovis, with its distinctive biface, blade and osseous technologies, is the oldest widespread archaeological complex defined in North America, dating from 11,100 to 10,700 (14)C years before present (bp) (13,000 to 12,600 calendar years bp). Nearly 50 years of archaeological research point to the Clovis complex as having developed south of the North American ice sheets from an ancestral technology. However, both the origins and the genetic legacy of the people who manufactured Clovis tools remain under debate. It is generally believed that these people ultimately derived from Asia and were directly related to contemporary Native Americans. An alternative, Solutrean, hypothesis posits that the Clovis predecessors emigrated from southwestern Europe during the Last Glacial Maximum. Here we report the genome sequence of a male infant (Anzick-1) recovered from the Anzick burial site in western Montana. The human bones date to 10,705 ± 35 (14)C years bp (approximately 12,707-12,556 calendar years bp) and were directly associated with Clovis tools. We sequenced the genome to an average depth of 14.4× and show that the gene flow from the Siberian Upper Palaeolithic Mal'ta population into Native American ancestors is also shared by the Anzick-1 individual and thus happened before 12,600 years bp. We also show that the Anzick-1 individual is more closely related to all indigenous American populations than to any other group. Our data are compatible with the hypothesis that Anzick-1 belonged to a population directly ancestral to many contemporary Native Americans. Finally, we find evidence of a deep divergence in Native American populations that predates the Anzick-1 individual.


Asunto(s)
Genoma Humano/genética , Indígenas Norteamericanos/genética , Filogenia , Arqueología , Asia/etnología , Huesos , Entierro , Cromosomas Humanos Y/genética , ADN Mitocondrial/genética , Emigración e Inmigración/historia , Europa (Continente)/etnología , Flujo Génico/genética , Haplotipos/genética , Historia Antigua , Humanos , Lactante , Masculino , Modelos Genéticos , Datos de Secuencia Molecular , Montana , Dinámica Poblacional , Datación Radiométrica
10.
Proc Natl Acad Sci U S A ; 110(29): 11791-6, 2013 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-23733930

RESUMEN

Human genetic diversity in southern Europe is higher than in other regions of the continent. This difference has been attributed to postglacial expansions, the demic diffusion of agriculture from the Near East, and gene flow from Africa. Using SNP data from 2,099 individuals in 43 populations, we show that estimates of recent shared ancestry between Europe and Africa are substantially increased when gene flow from North Africans, rather than Sub-Saharan Africans, is considered. The gradient of North African ancestry accounts for previous observations of low levels of sharing with Sub-Saharan Africa and is independent of recent gene flow from the Near East. The source of genetic diversity in southern Europe has important biomedical implications; we find that most disease risk alleles from genome-wide association studies follow expected patterns of divergence between Europe and North Africa, with the principal exception of multiple sclerosis.


Asunto(s)
Flujo Génico/genética , Variación Genética , Genética de Población , Población Blanca/genética , Población Blanca/historia , África del Norte , Demografía , Europa (Continente) , Haplotipos/genética , Historia Antigua , Humanos , Polimorfismo de Nucleótido Simple/genética
11.
PLoS Genet ; 8(1): e1002397, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22253600

RESUMEN

North African populations are distinct from sub-Saharan Africans based on cultural, linguistic, and phenotypic attributes; however, the time and the extent of genetic divergence between populations north and south of the Sahara remain poorly understood. Here, we interrogate the multilayered history of North Africa by characterizing the effect of hypothesized migrations from the Near East, Europe, and sub-Saharan Africa on current genetic diversity. We present dense, genome-wide SNP genotyping array data (730,000 sites) from seven North African populations, spanning from Egypt to Morocco, and one Spanish population. We identify a gradient of likely autochthonous Maghrebi ancestry that increases from east to west across northern Africa; this ancestry is likely derived from "back-to-Africa" gene flow more than 12,000 years ago (ya), prior to the Holocene. The indigenous North African ancestry is more frequent in populations with historical Berber ethnicity. In most North African populations we also see substantial shared ancestry with the Near East, and to a lesser extent sub-Saharan Africa and Europe. To estimate the time of migration from sub-Saharan populations into North Africa, we implement a maximum likelihood dating method based on the distribution of migrant tracts. In order to first identify migrant tracts, we assign local ancestry to haplotypes using a novel, principal component-based analysis of three ancestral populations. We estimate that a migration of western African origin into Morocco began about 40 generations ago (approximately 1,200 ya); a migration of individuals with Nilotic ancestry into Egypt occurred about 25 generations ago (approximately 750 ya). Our genomic data reveal an extraordinarily complex history of migrations, involving at least five ancestral populations, into North Africa.


Asunto(s)
Población Negra/genética , Flujo Génico/genética , Variación Genética , Dinámica Poblacional , Población , África del Sur del Sahara/etnología , África del Norte , Población Negra/historia , ADN Mitocondrial/genética , Antiguo Egipto , Emigración e Inmigración , Europa (Continente) , Pool de Genes , Genómica , Genotipo , Haplotipos , Historia Antigua , Humanos , Medio Oriente , Marruecos , Polimorfismo de Nucleótido Simple , Población Blanca/genética , Población Blanca/historia
12.
PLoS Genet ; 5(10): e1000695, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19851460

RESUMEN

Demographic models built from genetic data play important roles in illuminating prehistorical events and serving as null models in genome scans for selection. We introduce an inference method based on the joint frequency spectrum of genetic variants within and between populations. For candidate models we numerically compute the expected spectrum using a diffusion approximation to the one-locus, two-allele Wright-Fisher process, involving up to three simultaneous populations. Our approach is a composite likelihood scheme, since linkage between neutral loci alters the variance but not the expectation of the frequency spectrum. We thus use bootstraps incorporating linkage to estimate uncertainties for parameters and significance values for hypothesis tests. Our method can also incorporate selection on single sites, predicting the joint distribution of selected alleles among populations experiencing a bevy of evolutionary forces, including expansions, contractions, migrations, and admixture. We model human expansion out of Africa and the settlement of the New World, using 5 Mb of noncoding DNA resequenced in 68 individuals from 4 populations (YRI, CHB, CEU, and MXL) by the Environmental Genome Project. We infer divergence between West African and Eurasian populations 140 thousand years ago (95% confidence interval: 40-270 kya). This is earlier than other genetic studies, in part because we incorporate migration. We estimate the European (CEU) and East Asian (CHB) divergence time to be 23 kya (95% c.i.: 17-43 kya), long after archeological evidence places modern humans in Europe. Finally, we estimate divergence between East Asians (CHB) and Mexican-Americans (MXL) of 22 kya (95% c.i.: 16.3-26.9 kya), and our analysis yields no evidence for subsequent migration. Furthermore, combining our demographic model with a previously estimated distribution of selective effects among newly arising amino acid mutations accurately predicts the frequency spectrum of nonsynonymous variants across three continental populations (YRI, CHB, CEU).


Asunto(s)
Evolución Molecular , Frecuencia de los Genes , Polimorfismo de Nucleótido Simple , Grupos Raciales/genética , Grupos Raciales/historia , África , Asia , Demografía , Europa (Continente) , Historia Antigua , Humanos , Modelos Genéticos
13.
Bioinformatics ; 21 Suppl 1: i126-35, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15961449

RESUMEN

MOTIVATION: The evolution of protein sequences is constrained by complex interactions between amino acid residues. Because harmful substitutions may be compensated for by other substitutions at neighboring sites, residues can coevolve. We describe a Bayesian phylogenetic approach to the detection of coevolving residues in protein families. This method, Bayesian mutational mapping (BMM), assigns mutations to the branches of the evolutionary tree stochastically, and then test statistics are calculated to determine whether a coevolutionary signal exists in the mapping. Posterior predictive P-values provide an estimate of significance, and specificity is maintained by integrating over uncertainty in the estimation of the tree topology, branch lengths and substitution rates. A coevolutionary Markov model for codon substitution is also described, and this model is used as the basis of several test statistics. RESULTS: Results on simulated coevolutionary data indicate that the BMM method can successfully detect nearly all coevolving sites when the model has been correctly specified, and that non-parametric statistics such as mutual information are generally less powerful than parametric statistics. On a dataset of eukaryotic proteins from the phosphoglycerate kinase (PGK) family, interdomain site contacts yield a significantly greater coevolutionary signal than interdomain non-contacts, an indication that the method provides information about interacting sites. Failure to account for the heterogeneity in rates across sites in PGK resulted in a less discriminating test, yielding a marked increase in the number of reported positives at both contact and non-contact sites. SUPPLEMENTARY INFORMATION: http://www.dimmic.net/supplement/


Asunto(s)
Aminoácidos/química , Mapeo Cromosómico/métodos , Biología Computacional/métodos , Análisis Mutacional de ADN , Teorema de Bayes , Sitios de Unión , Evolución Molecular , Funciones de Verosimilitud , Cadenas de Markov , Modelos Estadísticos , Familia de Multigenes , Mutación , Fosfoglicerato Quinasa/genética
14.
Science ; 306(5704): 2081-4, 2004 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-15604405

RESUMEN

The shift to self-pollination is one of the most prevalent evolutionary transitions in flowering plants. In the selfing plant Arabidopsis thaliana, pseudogenes at the SCR and SRK self-incompatibility loci are believed to underlie the evolution of self-fertilization. Positive directional selection has driven the evolutionary fixation of pseudogene alleles of SCR, leading to substantially reduced nucleotide variation. Coalescent simulations indicate that this adaptive event may have occurred very recently and is possibly associated with the post-Pleistocene expansion of A. thaliana from glacial refugia. This suggests that ancillary morphological innovations associated with self-pollination can evolve rapidly after the inactivation of the self-incompatibility response.


Asunto(s)
Arabidopsis/genética , Arabidopsis/fisiología , Genes de Plantas , Proteínas Quinasas/genética , Seudogenes , Selección Genética , Alelos , Evolución Biológica , Mapeo Cromosómico , Clima , ADN Intergénico , Variación Genética , Genoma de Planta , Geografía , Haplotipos , Funciones de Verosimilitud , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Filogenia , Proteínas de Plantas , Polen , Polimorfismo Genético , Polimorfismo de Nucleótido Simple , Proteínas Quinasas/fisiología , Recombinación Genética , Tiempo
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