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Genes (Basel) ; 15(4)2024 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-38674333


There is an urgent need to find a way to improve the genetic diversity of captive South China tiger (SCT, Panthera tigris amoyensis), the most critically endangered taxon of living tigers, facing inbreeding depression. The genomes showed that 13 hybrid SCTs from Meihuashan were divided into two groups; one group included three individuals who had a closer relationship with pureblood SCTs than another group. The three individuals shared more that 40% of their genome with pureblood SCTs and might be potential individuals for genetic rescuing in SCTs. A large-scale genetic survey based on 319 pureblood SCTs showed that the mean microsatellite inbreeding coefficient of pureblood SCTs decreased significantly from 0.1789 to 0.0600 (p = 0.000009) and the ratio of heterozygous loci increased significantly from 38.5% to 43.2% (p = 0.02) after one individual of the Chongqing line joined the Suzhou line and began to breed in the mid-1980s, which is a reason why the current SCTs keep a moderate level of microsatellite heterozygosity and nucleotide diversity. However, it is important to establish a back-up population based on the three individuals through introducing one pureblood SCT into the back-up population every year. The back-up population should be an important reserve in case the pureblood SCTs are in danger in the future.

Especies en Peligro de Extinción , Repeticiones de Microsatélite , Tigres , Tigres/genética , Animales , Repeticiones de Microsatélite/genética , China , Variación Genética , Endogamia , Femenino , Masculino , Conservación de los Recursos Naturales/métodos , Cruzamiento
Conserv Biol ; : e14254, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38563102


Conservation translocations are an important conservation tool commonly employed to augment declining or reestablish extirpated populations. One goal of augmentation is to increase genetic diversity and reduce the risk of inbreeding depression (i.e., genetic rescue). However, introducing individuals from significantly diverged populations risks disrupting coadapted traits and reducing local fitness (i.e., outbreeding depression). Genetic data are increasingly more accessible for wildlife species and can provide unique insight regarding the presence and retention of introduced genetic variation from augmentation as an indicator of effectiveness and adaptive similarity as an indicator of source and recipient population suitability. We used 2 genetic data sets to evaluate augmentation of isolated populations of greater sage-grouse (Centrocercus urophasianus) in the northwestern region of the species range (Washington, USA) and to retrospectively evaluate adaptive divergence among source and recipient populations. We developed 2 statistical models for microsatellite data to evaluate augmentation outcomes. We used one model to predict genetic diversity after augmentation and compared these predictions with observations of genetic change. We used the second model to quantify the amount of observed reproduction attributed to transplants (proof of population integration). We also characterized genome-wide adaptive divergence among source and recipient populations. Observed genetic diversity (HO = 0.65) was higher in the recipient population than predicted had no augmentation occurred (HO = 0.58) but less than what was predicted by our model (HO = 0.75). The amount of shared genetic variation between the 2 geographically isolated resident populations increased, which is evidence of periodic gene flow previously assumed to be rare. Among candidate adaptive genes associated with elevated fixation index (FST) (143 genes) or local environmental variables (97 and 157 genes for each genotype-environment association method, respectively), we found clusters of genes with related functions that may influence the ability of transplants to use local resources and navigate unfamiliar environments and their reproductive potential, all possible reasons for low genetic retention from augmentation.

Influencia potencial de la divergencia adaptativa a nivel genoma sobre el resultado de la reubicación para conservación en una población aislada de urogallo mayor Resumen Las reubicaciones para conservación son una herramienta importante que se usa con frecuencia para aumentar las poblaciones en declinación o reestablecer las poblaciones erradicadas. Una de las metas de este aumento es incrementar la diversidad genética y reducir el riesgo de depresión endogámica (es decir, rescate genético). Sin embargo, la introducción de individuos de una población con divergencia significativa puede perturbar los rasgos coadaptados y reducir la aptitud local (es decir, depresión exogámica). La información genética es cada vez más accesible para las especies silvestres y puede proporcionar conocimiento único con respecto a la presencia y retención de la variación genética introducida a partir del aumento como un indicador de eficiencia y las similitudes adaptativas como un indicador de la idoneidad de la población de origen y la receptora. Usamos dos conjuntos de datos genéticos para evaluar el aumento de las poblaciones aisladas del urogallo mayor (Centrocercus urophasianus) en la región noroeste de la distribución de la especie (Washington, EUA) y para evaluar de forma retrospectiva la divergencia adaptativa entre la población de origen y la receptora. Desarrollamos dos modelos estadísticos para los datos microsatelitales para así evaluar los resultados del aumento. Usamos un modelo para predecir la diversidad genética después del aumento y comparamos estas predicciones con observaciones del cambio genético. Usamos el segundo modelo para cuantificar el aumento de la reproducción observada atribuida a las reubicaciones (evidencia de la integración poblacional). También caracterizamos la divergencia adaptativa a nivel genoma entre la población de origen y la población receptora. La diversidad genética observada (HO = 0.65) fue mayor de lo que se predijo en la población receptora de no haber ocurrido el aumento (HO = 0.58) pero menor de lo que se predijo en nuestro modelo (HO = 0.75). El aumento de la variación genética compartida entre las dos poblaciones residentes geográficamente aisladas incrementó, lo cual es evidencia de un flujo génico periódico que antes se supuso casi no ocurría. Entre los genes adaptativos candidatos asociados a una FST elevada (143 genes) o a variables ambientales locales (97 y 157 genes para cada método de asociación entre el ambiente y el genotipo, respectivamente) encontramos grupos de genes con funciones relacionadas que pueden influir sobre la habilidad de cada reubicación para usar recursos locales y navegar ambientes desconocidos y su potencial reproductivo, todas posibles razones para la baja retención genética en el aumento.

Sci Rep ; 14(1): 8088, 2024 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-38582794


The Amur tiger is currently confronted with challenges of anthropogenic development, leading to its population becoming fragmented into two geographically isolated groups: smaller and larger ones. Small and isolated populations frequently face a greater extinction risk, yet the small tiger population's genetic status and survival potential have not been assessed. Here, a total of 210 samples of suspected Amur tiger feces were collected from this small population, and the genetic background and population survival potentials were assessed by using 14 microsatellite loci. Our results demonstrated that the mean number of alleles in all loci was 3.7 and expected heterozygosity was 0.6, indicating a comparatively lower level of population genetic diversity compared to previously reported studies on other subspecies. The genetic estimates of effective population size (Ne) and the Ne/N ratio were merely 7.6 and 0.152, respectively, representing lower values in comparison to the Amur tiger population in Sikhote-Alin (the larger group). However, multiple methods have indicated the possibility of genetic divergence within our isolated population under study. Meanwhile, the maximum kinship recorded was 0.441, and the mean inbreeding coefficient stood at 0.0868, both of which are higher than those observed in other endangered species, such as the African lion and the grey wolf. Additionally, we have identified a significant risk of future extinction if the lethal equivalents were to reach 6.26, which is higher than that of other large carnivores. Further, our simulation results indicated that an increase in the number of breeding females would enhance the prospects of this population. In summary, our findings provide a critical theoretical basis for further bailout strategies concerning Amur tigers.

Leones , Tigres , Animales , Femenino , Tigres/genética , Especies en Peligro de Extinción , Heterocigoto , Densidad de Población , Repeticiones de Microsatélite/genética , Leones/genética , Conservación de los Recursos Naturales , Variación Genética
Mol Ecol ; 33(11): e17353, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38613250


Effective population size (Ne) is a particularly useful metric for conservation as it affects genetic drift, inbreeding and adaptive potential within populations. Current guidelines recommend a minimum Ne of 50 and 500 to avoid short-term inbreeding and to preserve long-term adaptive potential respectively. However, the extent to which wild populations reach these thresholds globally has not been investigated, nor has the relationship between Ne and human activities. Through a quantitative review, we generated a dataset with 4610 georeferenced Ne estimates from 3829 populations, extracted from 723 articles. These data show that certain taxonomic groups are less likely to meet 50/500 thresholds and are disproportionately impacted by human activities; plant, mammal and amphibian populations had a <54% probability of reaching N ̂ e = 50 and a <9% probability of reaching N ̂ e = 500. Populations listed as being of conservation concern according to the IUCN Red List had a smaller median N ̂ e than unlisted populations, and this was consistent across all taxonomic groups. N ̂ e was reduced in areas with a greater Global Human Footprint, especially for amphibians, birds and mammals, however relationships varied between taxa. We also highlight several considerations for future works, including the role that gene flow and subpopulation structure plays in the estimation of N ̂ e in wild populations, and the need for finer-scale taxonomic analyses. Our findings provide guidance for more specific thresholds based on Ne and help prioritise assessment of populations from taxa most at risk of failing to meet conservation thresholds.

Anfibios , Conservación de los Recursos Naturales , Genética de Población , Mamíferos , Densidad de Población , Animales , Anfibios/genética , Anfibios/clasificación , Mamíferos/genética , Mamíferos/clasificación , Flujo Génico , Aves/genética , Aves/clasificación , Humanos , Endogamia , Flujo Genético , Plantas/genética , Plantas/clasificación , Actividades Humanas
Anim Genet ; 55(3): 484-489, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38500412


China was the first country in the world to breed goldfish and has generated many unique goldfish varieties, including the most aristocratic Chinese palace goldfish. Due to the lack of scientific research on Chinese palace goldfish, their selection and breeding are mainly carried out through traditional hybridization, leading to serious inbreeding and the degradation of germplasm resources. To this end, whole-genome resequencing was performed to understand the genetic variation among three different varieties (eggpompons, goosehead, and tigerhead) from nine core conserved populations in China. A total of 15 polymorphic SSRs were developed for population genetics, and all tested populations were considered moderately polymorphic with an average polymorphism information content value of 0.4943. Genetic diversity in different varieties showed that all conserved populations were well protected with the potential for continued exploitation. This study provides reliable molecular tools and a basis for designing conservation and management programs in Chinese palace goldfish.

Carpa Dorada , Polimorfismo Genético , Secuenciación Completa del Genoma , Animales , Carpa Dorada/genética , China , Secuenciación Completa del Genoma/veterinaria , Repeticiones de Microsatélite , Marcadores Genéticos , Genética de Población , Cruzamiento , Conservación de los Recursos Naturales , Pueblos del Este de Asia
J Hered ; 115(3): 292-301, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38364316


Biodiversity conservation is a top priority in the face of global environmental change, and the practical restoration of biodiversity has emerged as a key objective. Nevertheless, the question of how to effectively contribute to biodiversity restoration and identify suitable systems for such efforts continues to present major challenges. By using genome-wide SNP data, our study revealed that populations from different mountain ranges of the Formosan Long-Arm Scarab beetle, a flagship species that receives strict protection, exhibited a single genetic cluster with no subdivision. Additionally, our result implied an association between the demographic history and historical fluctuations in climate and environmental conditions. Furthermore, we showed that, despite a stable and moderately sized effective population over recent history, all the individuals we studied exhibited signs of genetic inbreeding. We argued that the current practice of protecting the species as one evolutionarily significant unit remains the best conservation plan and that recent habitat change may have led to the pattern of significant inbreeding. We closed by emphasizing the importance of conservation genetic studies in guiding policy decisions and highlighting the potential of genomic data for identifying ideal empirical systems for genetic rescue, or assisted gene flow studies.

Escarabajos , Conservación de los Recursos Naturales , Genética de Población , Endogamia , Densidad de Población , Animales , Escarabajos/genética , Polimorfismo de Nucleótido Simple , Ecosistema , Flujo Génico , Genómica/métodos , Variación Genética , Biodiversidad
Plant Foods Hum Nutr ; 79(2): 425-431, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38383946


The evergreen tree species Aquilaria sinensis holds significant economic importance due to its specific medicinal values and increasing market demand. However, the unrestricted illegal exploitation of its wild population poses a threat to its survival. This study aims to contribute to the conservation efforts of A. sinensis by constructing a library database of DNA barcodes, including two chloroplast genes (psbA-trnH and matK) and two nuclear genes (ITS and ITS2). Additionally, the genetic diversity and structure were estimated using inter-simple sequence repeats (ISSR) markers. Four barcodes of 57 collections gained 194 sequences, and 1371 polymorphic bands (98.63%) were observed using DNA ISSR fingerprinting. The Nei's gene diversity (H) of A. sinensis at the species level is 0.2132, while the Shannon information index (I) is 0.3128. The analysis of molecular variance revealed a large significant proportion of total genetic variations and differentiation among populations (Gst = 0.4219), despite a relatively gene flow (Nm = 0.6853) among populations, which were divided into two groups by cluster analysis. There was a close genetic relationship among populations with distances of 0.0845 to 0.5555. This study provides evidence of the efficacy and dependability of establishing a DNA barcode database and using ISSR markers to assess the extent of genetic diversity A. sinensis. Preserving the genetic resources through the conservation of existing populations offers a valuable proposition. The effective utilization of these resources will be further deliberated in subsequent breeding endeavors, with the potential to breed agarwood commercial lines.

Conservación de los Recursos Naturales , Código de Barras del ADN Taxonómico , Variación Genética , Repeticiones de Microsatélite , Thymelaeaceae , Código de Barras del ADN Taxonómico/métodos , Thymelaeaceae/genética , Thymelaeaceae/clasificación , ADN de Plantas/genética , Marcadores Genéticos , Filogenia
Conserv Biol ; 38(1): e14154, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37489292


Human water use combined with a recent megadrought have reduced river and stream flow through the southwest United States and led to periodic drying of formerly perennial river segments. Reductions in snowmelt runoff and increased extent of drying collectively threaten short-lived, obligate aquatic species, including the endangered Rio Grande silvery minnow (Hybognathus amarus). This species is subject to boom-and-bust population dynamics, under which large fluctuations in abundance are expected to lower estimates of effective population size and erode genetic diversity over time. Rates of diversity loss are also affected by additions of hatchery-origin fish used to supplement the wild population. We used demographic and genetic data from wild and hatchery individuals to examine the relationship of genetic diversity and effective population size to abundance over the last two decades. Genetic diversity was low during the early 2000s, but diversity and demographic metrics stabilized after the hatchery program was initiated and environmental conditions improved. Yet, from 2017 onward, allelic diversity declined (Cohen's d = 1.34) and remained low despite hatchery stocking and brief wild population recovery. Across the time series, single-sample estimates of effective population size based on linkage disequilibrium (LD Ne ) were positively associated (r = 0.53) with wild abundance and total abundance, but as the proportion of hatchery-origin spawners increased, LD Ne declined (r = -0.55). Megadrought limited wild spawner abundance and precluded refreshment of hatchery brood stocks with wild fish; hence, we predict a riverine population increasingly dominated by hatchery-origin individuals and accelerated loss of genetic diversity despite supplementation. We recommend an adaptive and accelerated management plan that integrates river flow management and hatchery operations to slow the pace of genetic diversity loss exacerbated by megadrought.

El uso humano del agua, combinado con una megasequía reciente, ha reducido el flujo de los ríos y arroyos en el suroeste de los Estados Unidos y ha provocado la seca periódica de segmentos de ríos que antes eran perennes. Las reducciones en la escorrentía del deshielo y el aumento de la sequía amenazan colectivamente a especies obligatoriamente acuáticas de vida corta, incluyendo la amenazada carpa chamizal (Hybognathus amarus). Esta especie está sujeta a una dinámica poblacional de explosión y colapso, bajo la cual se espera que grandes fluctuaciones en la abundancia reduzcan las estimaciones del tamaño efectivo de la población y erosionen la diversidad genética con el tiempo. Las tasas de pérdida de la diversidad también se ven afectadas por la adición de peces procedentes de criaderos usados para suplementar la población silvestre. Utilizamos datos demográficos y genéticos de individuos silvestres y de criaderos para examinar la relación entre la diversidad genética y el tamaño efectivo de la población con la abundancia durante las últimas dos décadas. La diversidad genética fue baja a principios de los 2000, pero las métricas de diversidad y demografía estabilizaron después de que se inició el programa de criadero y mejoraron las condiciones ambientales. Sin embargo, a partir de 2017, la diversidad alélica disminuyó (d de Cohen = 1,34) y se mantuvo baja a pesar de la suplementación con individuos de criaderos y la breve recuperación de la población silvestre. A lo largo del tiempo, las estimativas de muestras individuales del tamaño efectivo de la población basados en el desequilibrio de ligamiento (LD Ne) estaban asociadas positivamente (r = 0,53) con la abundancia silvestre y la abundancia total, pero a medida que la proporción de desovadores originados en criaderos aumentó, el LD Ne disminuyó (r = -0,55). La megasequía limitó la abundancia de desovadores silvestres e impidió el reabastecimiento de las poblaciones en cautiverio con peces silvestres; por lo tanto, predecimos una población ribereña cada vez más dominada por individuos procedentes de criaderos y una pérdida acelerada de diversidad genética a pesar de la suplementación. Recomendamos un plan de gestión adaptativo y acelerado que integre la gestión del caudal del río y las operaciones de criaderos para frenar el ritmo de pérdida de diversidad genética exacerbada por la megasequía.

Cyprinidae , Variación Genética , Humanos , Animales , Conservación de los Recursos Naturales , Cyprinidae/genética , Ríos , Cruzamiento
Braz. j. biol ; 84: e256160, 2024. tab, graf, mapas, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1360203


Riverine forests are unique and highly significant ecosystems that are globally important for diverse and threatened avian species. Apart from being a cradle of life, it also serves as a gene pool that harbors a variety of flora and fauna species (repeated below). Despite the fact, this fragile ecosystem harbored avian assemblages; it is now disappearing daily as a result of human activity. Determining habitat productivity using bird species is critical for conservation and better management in the future. Multiple surveys were conducted over a 15-month period, from January to March 2019, using the distance sampling point count method. A total of 250 point count stations were fixed systematically at 300 m intervals. In total, 9929 bird individuals were recorded, representing 57 species and 34 families. Out of 57 bird species, two were vulnerable, one was data deficient, one was nearly threatened, and the remaining 53 species were of least concern. The Eurasian Collard Dove - Streptopelia decaocto (14.641 ± 2.532/ha), White-eared Bulbul - Pycnonotus leucotis (13.398 ± 4.342/ha) and Common Babbler - Turdoides caudata (10.244 ± 2.345/ha) were the three first plenteous species having higher densities. However, the densities of three species, i.e., Lesser Whitethroat - Sylvia curruca, Gray Heron - Ardea cinerea and Pallas Fish Eagle - Haliaeetus leucoryphus, were not analyzed due to the small sample size. The findings of diversity indices revealed that riverine forest has harbored the diverse avian species that are uniformly dispersed across the forest. Moreover, recording the ten foraging guilds indicated that riverine forest is rich in food resources. In addition, the floristic structure importance value index results indicated that riverine forest is diverse and rich in flora, i.e. trees, shrubs, weeds and grass, making it an attractive and productive habitat for bird species.

As florestas ribeirinhas são ecossistemas únicos e altamente significativos que são globalmente importantes para diversas espécies de aves ameaçadas de extinção. Além de serem o berço da vida, também servem como um conjunto genético que abriga uma variedade de espécies da flora e da fauna. Apesar disso, esse frágil ecossistema abrigava um conjunto de aves, mas agora está desaparecendo diariamente como resultado da atividade humana. Determinar a produtividade do hábitat usando espécies de pássaros é fundamental para a conservação e melhor gestão no futuro. Vários levantamentos foram realizados ao longo de um período de 15 meses, de janeiro de 2018 a março de 2019, por meio do método de contagem de pontos de amostragem de distância. Foram fixadas sistematicamente 250 estações de contagem de pontos em intervalos de 300 m. No total, foram registrados 9.929 indivíduos de aves, representando 57 espécies e 34 famílias. Das 57 espécies de aves, duas eram vulneráveis, uma tinha dados insuficientes, uma estava quase ameaçada e as 53 espécies restantes eram as menos preocupantes. O: Pomba de colar euroasiática - Streptopelia decaocto (14.641 ± 2.532/ha), o Bulbul de orelha branca - Pycnonotus leucotis (13.398 ± 4.342/ha) e Tagarela comum - Turdoides caudata (10.244 ± 2.345/ha) foram as três primeiras espécies abundantes com maiores densidades. No entanto, as densidades de três espécies, Papa-amoras-cinzento (Sylvia curruca), Garça-real-europeia (Ardea cinerea) e Águia-pescadora de Pallas (Haliaeetus leucoryphus), não foram analisadas por causa do pequeno tamanho da amostra. Os resultados dos índices de diversidade revelaram que a floresta ribeirinha abrigou diversas espécies de aves que estão uniformemente dispersas pela floresta. Além disso, o registro das dez guildas de forrageamento indicou que a floresta ribeirinha é rica em recursos alimentares. Além disso, os resultados do índice de valor de importância da estrutura florística indicaram que a floresta ribeirinha é variada e rica em flora, ou seja, árvores, arbustos, ervas daninhas e grama, tornando-a um hábitat atraente e produtivo para espécies de aves.

Aves , Bosques , Ecosistema , Antecedentes Genéticos
Anim Genet ; 55(2): 177-192, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38123142


Wildlife-related crimes are the second most prevalent lawbreaking offense globally. This illicit trade encompasses hunting, breeding and trafficking. Besides diminishing many species and their habitats and ecosystems, hindering the economic development of local communities that depend on them, undermining the rule of law and financing terrorism, various cross-species transmissions (zoonoses) of pathogens, including COVID-19, can be attributed to wildlife crimes. Wildlife forensics applies interdisciplinary scientific analyses to support law enforcement in investigating wildlife crimes. Its main objectives are to identify the taxonomic species in question, determine if a crime has been committed, link a suspect to the crime and support the conviction and prosecution of the perpetrator. This article reviews wildlife crime and its implications, wildlife forensic science investigation, common forms of wildlife biological evidence, including DNA, wildlife DNA techniques and challenges in wildlife forensic genetics. The article also reviews the contributions of genetic markers such as short tandem repeat (STR) and mitochondrial DNA (mtDNA) markers, which provide the probative genetic data representing the bulk of DNA evidence for solving wildlife crime. This review provides an overview of wildlife DNA databases, which are critical for searching and matching forensic DNA profiles and sequences and establishing how frequent forensic DNA profiles and sequences are in a particular population or geographic region. As such, this review will contain an in-depth analysis of the current status of wildlife forensic genetics, and it will be of general interest to wildlife and conservation biologists, law enforcement officers, and academics interested in combating crimes against wildlife using animal forensic DNA methods.

Animales Salvajes , Genética Forense , Animales , Animales Salvajes/genética , Marcadores Genéticos , Genética Forense/métodos , Ecosistema , ADN Mitocondrial/genética , Conservación de los Recursos Naturales
Ophthalmic Genet ; 44(6): 553-558, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37530443


BACKGROUND: Genetic counselors (GCs) have practiced in Inherited Retinal Disease (IRD) clinics for several decades. In this small subspecialty of genetic counseling, GCs are critical for patient understanding of genetic information, which can have prognostic, systemic, family planning and therapeutic implications. Recently, both access to genetic testing for IRDs and the number of genes associated with IRDs (>350) has increased dramatically. However, the practice models and roles of IRD GCs have not been previously described. MATERIALS AND METHODS: GCs working in academic IRD clinics were surveyed to assess their experience, clinical practices, and roles performed. The collected data was compared to the broader genetic counseling profession and to other specialties using publicly available data on GC professional practices. RESULTS: While roles of IRD GCs were overlapping with those of the overall genetic counseling profession, all survey respondents reported diverse roles that included both clinical and non-clinical duties, spending up to half their time on research and educational responsibilities. Most respondents (89%) felt that their clinic's MD to GC ratio was too high, while clinical load varied. IRD GCs report varying degrees of prior genetic counseling and ophthalmology-specific experience but unanimously desire additional subspecialty-specific training. CONCLUSIONS: This descriptive assessment of a small subspecialty suggests a need for growth in the number of GCs practicing in IRD clinics and could help to inform development of new GC positions in IRD centers. It also highlights the desire for additional GC-specific education and may be relevant to curriculum development within GC programs.

Consejeros , Enfermedades de la Retina , Humanos , Consejeros/psicología , Asesoramiento Genético , Pruebas Genéticas , Enfermedades de la Retina/genética , Enfermedades de la Retina/terapia , Recursos Humanos
Clin Ther ; 45(8): 695-701, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37516568


Rapid growth in the volume of referrals to clinical genetics services in many countries during the past 15 years makes workforce planning a critical policy tool in ensuring that the capacity of the clinical genetics workforce is large enough to meet current and future needs. This article explores the distinctive challenges of workforce planning in clinical genetics and provides recommendations for addressing these challenges using a needs-based planning approach. Specifically, at least 3 features complicate efforts to estimate the need for clinical genetic services: the difficulty in linking many clinical genetic services to concrete health outcomes; the rapidly changing nature of genetic medicine, which creates intrinsic uncertainty about the appropriate level of service; and the heightened relevance of patient preferences in this context. Our recommendations call for needs-based planning studies to include an explicit definition of necessary care, to be flexible in considering nonhealth benefits, to err on the side of including services currently funded by health systems even when evidence about outcomes is limited, and to use scenario analysis and expert input to explore the impact of uncertainty about patients' preferences and future technologies on estimates of workforce requirements.

Servicios Genéticos , Necesidades y Demandas de Servicios de Salud , Humanos , Recursos Humanos
BAG, J. basic appl. genet. (Online) ; 34(1): 47-56, July 2023. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1447499


ABSTRACT One of the greatest challenges facing humanity is the development of sustainable strategies to ensure food availability in response to population growth and climate change. One approach that can contribute to increase food security is to close yield gaps and enhancing genetic gain; to such end, what is known as "molecular breeding" plays a fundamental role. Since a crop breeding program is mainly based on the quality of the germplasm, its detailed genetic characterization is mandatory to ensure the efficient use of genetic resources and accelerating development of superior varieties. Deep genotyping is an essential tool for a comprehensive characterization of the germplasm of interest and, fortunately, the technology is now accessible at a reasonable cost. What must be ensured is the correct interpretation of the genotypic information and on that basis develop efficient practical molecular crop breeding strategies that respond to the real needs of the breeding program.

RESUMEN Uno de los mayores desafíos que enfrenta la humanidad es el desarrollo de estrategias sostenibles para asegurar la disponibilidad de alimentos en respuesta al crecimiento de la población y el cambio climático. Un enfoque que puede contribuir a aumentar la seguridad alimentaria es cerrar las brechas de rendimiento y mejorar la ganancia genética; para tal fin, lo que se conoce como "mejoramiento molecular" juega un papel fundamental. Dado que un programa de mejoramiento de cultivos se basa principalmente en la calidad del germoplasma, su caracterización genética detallada es fundamental para garantizar el uso eficiente de los recursos genéticos y acelerar el desarrollo de variedades superiores. La genotipificación profunda es una herramienta esencial para una caracterización integral del germoplasma de interés y, afortunadamente, en la actualidad se puede acceder a la tecnología a un costo razonable. Lo que debe asegurarse es la interpretación correcta de la información genotípica y sobre esa base desarrollar estrategias eficientes y prácticas de mejoramiento molecular de cultivos que respondan a las necesidades reales del programa de mejoramiento.

Conserv Biol ; 37(6): e14133, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37259604


Reduction in population size, with its predicted effects on population fitness, is the most alarming anthropogenic impact on endangered species. By introducing compatible individuals, genetic rescue (GR) is a promising but debated approach for reducing the genetic load unmasked by inbreeding and for restoring the fitness of declining populations. Although GR can improve genetic diversity and fitness, it can also produce loss of ancestry, hampering local adaptation, or replace with introduced variants the unique genetic pools evolved in endemic groups. We used forward genetic simulations based on empirical genomic data to assess fitness benefits and loss of ancestry risks of GR in the Apennine brown bear (Ursus arctos marsicanus). There are approximately 50 individuals of this isolated subspecies, and they have lower genetic diversity and higher inbreeding than other European brown bears, and GR has been suggested to reduce extinction risks. We compared 10 GR scenarios in which the number and genetic characteristics of migrants varied with a non-GR scenario of simple demographic increase due to nongenetic factors. The introduction of 5 individuals of higher fitness or lower levels of deleterious mutations than the target Apennine brown bear from a larger European brown bear population produced a rapid 10-20% increase in fitness in the subspecies and up to 22.4% loss of ancestry over 30 generations. Without a contemporary demographic increase, fitness started to decline again after a few generations. Doubling the population size without GR gradually increased fitness to a comparable level, but without losing ancestry, thus resulting in the best strategy for the Apennine brown bear conservation. Our results highlight the importance for management of endangered species of realistic forward simulations grounded in empirical whole-genome data.

Consecuencias en la aptitud y pérdida de ascendencia del oso pardo de los Apeninos después de un rescate genético simulado Resumen La reducción del tamaño poblacional, con los previsibles efectos sobre su aptitud, es el impacto antropogénico más alarmante sobre las especies amenazadas. Mediante la introducción de individuos compatibles, el rescate genético (RG) es una estrategia prometedora para reducir la carga genética revelada por la endogamia y restaurar la aptitud de las poblaciones en declive, aunque todavía se debate la eficiencia de esta. Aunque el RG puede mejorar la diversidad genética y la aptitud, también puede producir pérdida de ascendencia, lo que puede dificultar la adaptación local, o sustituir con variantes introducidas por los migrantes los acervos genéticos únicos que han evolucionado en grupos endémicos. En este trabajo realizamos simulaciones genéticas a futuro basadas en datos genómicos empíricos para evaluar los beneficios del RG en términos de aptitud y los riesgos de la pérdida de ascendencia en el oso pardo de los Apeninos (Ursus arctos marsicanus). Quedan aproximadamente 50 individuos de esta subespecie aislada que cuentan con una menor diversidad genética y un mayor nivel de endogamia comparado con otros osos pardos europeos y se ha sugerido que el RG podria reducir el riesgo de extinción de esta población. Comparamos 10 escenarios de RG en los que variaban el número y las características genéticas de los osos migrantes con un escenario sin RG con aumento demográfico causado por factores no genéticos. La introducción de 5 individuos procedentes de una población europea de oso pardo con mayor aptitud o niveles menores de mutaciones deletéreas que el oso pardo de los Apeninos produjo un rápido aumento de la aptitud del 10-20% en la subespecie y hasta un 22.4% de pérdida de ascendencia durante 30 generaciones. En las simulaciones sin un aumento demográfico, la aptitud empezó a disminuir de nuevo después de unas pocas generaciones. La duplicación del tamaño de la población sin RG aumentó gradualmente la aptitud hasta un nivel comparable al de algunos escenarios de RG, pero sin pérdida de ascendencia, por lo que parece ser la mejor estrategia para la conservación del oso pardo de los Apeninos. Nuestros resultados resaltan la importancia que tienen las simulaciones realistas a futuro basadas en datos empíricos del genoma completo para la gestión de especies amenazadas.

Ursidae , Humanos , Animales , Ursidae/genética , Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Genómica , Densidad de Población , Variación Genética
Med. infant ; 30(2): 204-213, Junio 2023. ilus, tab
Artículo en Español | LILACS, UNISALUD, BINACIS | ID: biblio-1443868


El Hospital Garrahan ha sido pionero en el diagnóstico molecular de patologías pediátricas en Argentina. Los avances tecnológicos de las últimas décadas en el área de la biología molecular, sentaron las bases para la optimización y ampliación del diagnóstico molecular a partir de la secuenciación masiva en paralelo de múltiples genes. El presente trabajo describe el proceso de implementación de los estudios de secuenciación de nueva generación y el desarrollo de la Unidad de Genómica en un hospital público pediátrico de alta complejidad, así como su impacto en las capacidades diagnósticas de enfermedades poco frecuentes de origen genético. La creación del Grupo Interdisciplinario de Estudios Genómicos constituyó la vía institucional para la toma de decisiones que implican la implementación de nuevos estudios genómicos y el establecimiento de prioridades diagnósticas, extendiendo la disponibilidad del diagnóstico molecular a más disciplinas. La Unidad de Genómica trabaja en diseñar las estrategias que permitan la mayor optimización de los recursos con los que cuenta el hospital, teniendo en cuenta el equipamiento disponible, las prioridades establecidas y la frecuencia de las distintas patologías. Se demuestra el salto significativo operado en nuestras capacidades diagnósticas, tanto en la variedad de enfermedades como en el número de genes analizados, habiendo estudiado a la fecha alrededor de 2.000 pacientes, muchos de los cuales ven de este modo finalizada su odisea diagnóstica. Los estudios de NGS se han convertido en una herramienta de la práctica diaria para la atención de un número importante de pacientes de nuestro hospital. Continuaremos trabajando para ampliar su aplicación a la mayor cantidad de patologías, a través de los mecanismos institucionales ya existentes (AU)

The Garrahan Hospital has been a pioneer in the molecular diagnosis of pediatric diseases in Argentina. The technological advances of the last decades in the area of molecular biology have laid the foundations for the optimization and expansion of molecular diagnostics through massive parallel sequencing of multiple genes. This study describes the process of implementation of next-generation sequencing studies and the development of the Genomics Unit in a public pediatric tertiary hospital, and its impact on the capacity to diagnose rare diseases of genetic origin. The creation of the Interdisciplinary Group of Genomic Studies constituted the institutional pathway for decision-making involving the implementation of new genomic studies and the establishment of diagnostic priorities, extending the availability of molecular diagnostics to additional disciplines. The Genomics Unit is working to design strategies that allow for optimization of the resources available to the hospital, taking into account the equipment available, the priorities established, and the frequency of the different diseases. It demonstrates the significant leap in our diagnostic capabilities, both in the variety of diseases and in the number of genes analyzed. To date, around 2,000 patients have been studies, many of whom have thus completed their diagnostic odyssey. NGS studies have become a tool in daily practice for the care of a significant number of patients in our hospital. We will continue working to expand its application to as many diseases as possible, through the existing institutional mechanisms (AU)

Humanos , Recién Nacido , Lactante , Preescolar , Niño , Adolescente , Genómica/instrumentación , Técnicas de Diagnóstico Molecular/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , Medicina Genómica/tendencias , Enfermedades Genéticas Congénitas/diagnóstico , Laboratorios de Hospital , Hospitales Pediátricos
J Hered ; 114(4): 354-366, 2023 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-36975379


Restoring gene flow among fragmented populations is discussed as a potentially powerful management strategy that could reduce inbreeding depression and cause genetic rescue. Yet, examples of assisted migration for genetic rescue remain sparse in conservation, prompting several outspoken calls for its increased use in genetic management of fragmented populations. We set out to evaluate the extent to which this strategy is underused and to determine how many imperiled species would realistically stand to benefit from genetic rescue, focusing on federally threatened or endangered vertebrate species in the United States. We developed a "genetic rescue suitability index (GR index)" based on concerns about small population problems relative to risks associated with outbreeding depression and surveyed the literature for 222 species. We found that two-thirds of these species were good candidates for consideration of assisted migration for the purpose of genetic rescue according to our suitability index. Good candidate species spanned all taxonomic groups and geographic regions, though species with more missing data tended to score lower on the suitability index. While we do not recommend a prescriptive interpretation of our GR index, we used it here to establish that assisted migration for genetic rescue is an underused strategy. For example, we found in total, "genetic rescue" was only mentioned in 11 recovery plans and has only been implemented in 3 of the species we surveyed. A potential way forward for implementation of this strategy is incorporating genetic rescue as a priority in USFWS recovery documentation. In general, our results suggest that although not appropriate for all imperiled species, many more species stand to benefit from a conservation strategy of assisted migration for genetic rescue than those for which it has previously been considered or implemented.

Conservación de los Recursos Naturales , Endogamia , Animales , Estados Unidos , Especies en Peligro de Extinción , Vertebrados/genética , Flujo Génico
Hipertens. riesgo vasc ; 40(1): 5-15, ene.-mar. 2023. ilus, tab, graf
Artículo en Inglés | IBECS | ID: ibc-217410


Background: Carotid intima media thickness (CIMT) is used as a marker of subclinical and asymptomatic atherosclerotic vascular disease. Increased CIMT is associated with future cerebrovascular and cardiovascular events. There is limited data on the profile and correlates of CIMT in Africa. The aim of this study was to describe the profile and correlates of CIMT in apparently normal younger-age adults in an urban setting in Kenya. Methods: This study used population-based data collected from 2003 adults between the ages of 40 and 60 years in two slums of Nairobi as part of a genetic study. CIMT was measured using LOGIQ e (GE Healthcare, CT, USA) ultrasound on both left and right carotid arteries, whereby maximum, mean, and minimum values were recorded. Age- and sex-specific CIMT measurements were calculated and their association with basic sociodemographic, behavioral and body composition indicators were investigated. Results: The median (IQR) CIMT were 0.58 (0.51, 0.66) and 0.59 (0.53, 0.66) in men and women, respectively. About 16% of the study population had CIMT greater than 0.7mm, the cut off for higher CIMT. Nearly 60% had CIMT values ≥75th percentile. Age, current use of alcohol, systolic blood pressure, subcutaneous fat thickness, pulse rate and pulse pressure were found to be the main predictors of CIMT in our study population. Conclusion: This study provided population-based reference values and predictors for CIMT for an adult population living in urban poor settings in Kenya. Future studies need to consider biochemical and genetic predictors of CIMT in this population. (AU)

Antecedentes: El grosor de la íntima-media carotídea (GIMc) se utiliza como marcador de la aterosclerosis subclínica y asintomática. El incremento del GIMc está asociado a episodios cerebrovasculares y cardiovasculares futuros. Existen datos limitados sobre el perfil y la correlación del GIMc en África. El objetivo de este estudio fue describir el perfil y la correlación del GIMc en adultos jóvenes aparentemente normales en un contexto urbano de Kenia. Métodos: Este estudio utilizó datos basados en población de 2.003 adultos con edades comprendidas entre 40 y 60 años en dos suburbios de Nairobi, como parte de un estudio genético. El GIMc se midió utilizando el ecógrafo LOGIQ E (GE Healthcare, CT, EE. UU.) en ambas carótidas, izquierda y derecha, donde se registraron los valores máximo, medio y mínimo. Se calcularon las medidas de GIMc específicas de la edad y el sexo, así como su asociación con los indicadores sociodemográficos, conductuales y corporales básicos. Resultados: Los valores medios (RIC) de GIMc fueron 0,58 (0,51, 0,66) y 0,59 (0,53, 0,66) en hombres y mujeres, respectivamente. Cerca del 16% de la población de estudio tuvo un GIMc superior a 0,7mm, siendo el punto de corte de GIMc elevado. Cerca del 60% reflejó valores de GIMc ≥percentil 75. La edad, el consumo actual de alcohol, la presión arterial sistólica, el grosor de la grasa subcutánea, la frecuencia cardiaca y la presión del pulso fueron los principales factores predictivos de GIMc en la población de nuestro estudio. Conclusión: Este estudio aportó valores de referencia basados en población y factores predictivos de GIMc para una población adulta en un entorno urbano de pocos recursos de Kenia. Los estudios futuros deberán considerar los factores predictivos bioquímicos y genéticos de GIMc en dicha población. (AU)

Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Grosor Intima-Media Carotídeo , Población Urbana , Áreas de Pobreza , Presión Arterial , Grasa Subcutánea
Mol Ecol ; 32(9): 2186-2205, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36798996


Understanding the factors that govern variation in genetic structure across species is key to the study of speciation and population genetics. Genetic structure has been linked to several aspects of life history, such as foraging strategy, habitat association, migration distance, and dispersal ability, all of which might influence dispersal and gene flow. Comparative studies of population genetic data from species with differing life histories provide opportunities to tease apart the role of dispersal in shaping gene flow and population genetic structure. Here, we examine population genetic data from sets of bird species specialized on a series of Amazonian habitat types hypothesized to filter for species with dramatically different dispersal abilities: stable upland forest, dynamic floodplain forest, and highly dynamic riverine islands. Using genome-wide markers, we show that habitat type has a significant effect on population genetic structure, with species in upland forest, floodplain forest, and riverine islands exhibiting progressively lower levels of structure. Although morphological traits used as proxies for individual-level dispersal ability did not explain this pattern, population genetic measures of gene flow are elevated in species from more dynamic riverine habitats. Our results suggest that the habitat in which a species occurs drives the degree of population genetic structuring via its impact on long-term fluctuations in levels of gene flow, with species in highly dynamic habitats having particularly elevated gene flow. These differences in genetic variation across taxa specialized in distinct habitats may lead to disparate responses to environmental change or habitat-specific diversification dynamics over evolutionary time scales.

A compreensão dos fatores que governam a variação da estrutura genética entre as espécies é fundamental para o estudo da especiação e da genética das populações. A estrutura genética tem sido ligada a vários aspectos da história da vida, tais como estratégia de forrageio, associação ao habitat, distância de migração e capacidade de dispersão, os quais poderiam influenciar a dispersão e o fluxo gênico. Estudos comparativos usando espécies que diferem nas suas histórias de vida oferecem uma oportunidade para desvendar o papel da dispersão no estabelecimento do fluxo gênico e da estrutura genética da população. Aqui examinamos dados genéticos populacionais de diversas espécies de aves com diferentes capacidades de dispersão especializadas em três habitats amazônicos, incluindo florestas de terra-firme, florestas de várzea e ilhas fluviais, cujos ambientes ripários são altamente dinâmicos. Utilizando dados genômicos que incluem milhares de loci, mostramos que o tipo de habitat tem um efeito significativo na estruturação genética das populações; espécies de florestas de terra-firme, florestas de várzea e ilhas fluviais exibem níveis de estruturação progressivamente menores. Embora os traços morfológicos frequentemente usados como indicadores da capacidade de dispersão a nível individual não expliquem este padrão, as medidas genéticas populacionais de fluxo gênico são altas em espécies associadas a habitats ribeirinhos mais dinâmicos. Nossos resultados sugerem que o habitat no qual uma espécie é encontrada determina o grau de estruturação genética da população através de seu impacto nas flutuações de longo prazo do fluxo gênico, com espécies em habitats altamente dinâmicos tendo um fluxo gênico particularmente alto. As diferenças na variação genética dos táxons especializados em diferentes habitats podem resultar em respostas díspares às mesmas mudanças ambientais, ou dinâmicas de diversificação específicas a um determinado habitat ao longo de escalas de tempo evolutivas.

Comprender los factores que rigen la variación de la estructura genética entre especies es clave para el estudio de la especiación y la genética de poblaciones. La estructura genética se ha relacionado con varios aspectos de la historia vital, como la estrategia de búsqueda de alimento, la asociación de hábitats, la distancia de migración y la capacidad de dispersión, factores todos ellos que podrían influir en la dispersión y el flujo genético. Los estudios comparativos de datos genéticos poblacionales de especies con historias vitales diferentes ofrecen la oportunidad de desentrañar el papel de la dispersión en la conformación del flujo genético y la estructura genética poblacional. En este trabajo examinamos los datos genéticos de poblaciones de especies de aves especializadas en una serie de hábitats amazónicos que, según la hipótesis, filtran especies con capacidades de dispersión radicalmente diferentes: bosques estables de tierras altas, bosques dinámicos de llanuras aluviales e islas fluviales altamente dinámicas. Utilizando marcadores genómicos, demostramos que el tipo de hábitat tiene un efecto significativo en la estructura genética de la población, y que las especies de los bosques de tierras altas, los bosques inundables y las islas fluviales presentan niveles de estructura progresivamente más bajos. Aunque los rasgos morfológicos utilizados como indicadores de la capacidad de dispersión individual no explican este patrón, las medidas genéticas poblacionales del flujo genético son más elevadas en las especies de hábitats fluviales más dinámicos. Nuestros resultados sugieren que el hábitat en el que se encuentra una especie determina el grado de estructuración genética de la población a través de su impacto en las fluctuaciones a largo plazo de los niveles de flujo genético, siendo las especies de hábitats muy dinámicos las que presentan un flujo genético particularmente elevado. Estas diferencias en la variación genética entre taxones especializados en hábitats distintos pueden dar lugar a respuestas dispares al cambio ambiental o a dinámicas de diversificación específicas del hbitat a lo largo de escalas temporales evolutivas.

Ecosistema , Flujo Génico , Animales , Bosques , Aves/genética , Genética de Población , Variación Genética
Conserv Biol ; 37(4): e14064, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36751982


The International Union for Conservation of Nature (IUCN) Red List is an important and widely used tool for conservation assessment. The IUCN uses information about a species' range, population size, habitat quality and fragmentation levels, and trends in abundance to assess extinction risk. Genetic diversity is not considered, although it affects extinction risk. Declining populations are more strongly affected by genetic drift and higher rates of inbreeding, which can reduce the efficiency of selection, lead to fitness declines, and hinder species' capacities to adapt to environmental change. Given the importance of conserving genetic diversity, attempts have been made to find relationships between red-list status and genetic diversity. Yet, there is still no consensus on whether genetic diversity is captured by the current IUCN Red List categories in a way that is informative for conservation. To assess the predictive power of correlations between genetic diversity and IUCN Red List status in vertebrates, we synthesized previous work and reanalyzed data sets based on 3 types of genetic data: mitochondrial DNA, microsatellites, and whole genomes. Consistent with previous work, species with higher extinction risk status tended to have lower genetic diversity for all marker types, but these relationships were weak and varied across taxa. Regardless of marker type, genetic diversity did not accurately identify threatened species for any taxonomic group. Our results indicate that red-list status is not a useful metric for informing species-specific decisions about the protection of genetic diversity and that genetic data cannot be used to identify threat status in the absence of demographic data. Thus, there is a need to develop and assess metrics specifically designed to assess genetic diversity and inform conservation policy, including policies recently adopted by the UN's Convention on Biological Diversity Kunming-Montreal Global Biodiversity Framework.

La diversidad genética y los estados de la Lista Roja de la UICN Resumen La Lista Roja de la Unión Internacional para la Conservación de la Naturaleza (UICN) es una importante herramienta de uso extendido para evaluar la conservación. La UICN utiliza datos sobre la distribución y tamaño poblacional de una especie, la calidad y niveles de fragmentación de su hábitat y sus tendencias de abundancia para valorar su riesgo de extinción, A pesar de que la diversidad genética afecta al riesgo de extinción, la UICN no la considera. La deriva génica y las tasas altas de endogamia afectan con mayor fuerza a las poblaciones en declinación, lo que puede reducir la eficiencia de la selección, derivar en la disminución de la aptitud y dificultar la capacidad de una especie de adaptarse ante el cambio ambiental. Se ha intentado encontrar la relación entre la diversidad genética y el estado en las listas rojas ya que su conservación es muy importante. Aun con lo anterior, no hay un consenso actual sobre si la diversidad genética está capturada en las categorías vigentes de la Lista Roja de la UICN de manera que sea informativa para la conservación. Para poder evaluar el poder predictivo de la correlación entre la diversidad genética y el estado en la Lista Roja de los vertebrados, sintetizamos trabajos previos y analizamos de nuevo los conjuntos de datos con base en tres tipos de información genética: ADN mitocondrial, microsatélites y genomas completos. Las especies con un estado de riesgo de extinción más alto fueron propensas a una diversidad genética más baja para todos los tipos de marcadores, aunque estas relaciones fueron débiles y variaron entre los taxones, lo cual es coherente con trabajos anteriores. Sin importar el tipo de marcador, la diversidad genética no fue un identificador certero de las especies amenazadas en ninguno de los grupos taxonómicos. Nuestros resultados indican que el estado de lista roja no es una medida útil para guiar las decisiones específicas por especie en relación con la protección de la diversidad genética. También indican que los datos genéticos no pueden usarse para identificar el estado de amenaza si no se tienen los datos demográficos. Por lo tanto, es necesario desarrollar y evaluar las medidas diseñadas específicamente para valorar la diversidad genética e informar las políticas de conservación, incluidas las que adoptó recientemente la ONU en el Convenio del Marco Mundial Kunming-Montreal de la Diversidad Biológica.

Conservación de los Recursos Naturales , Extinción Biológica , Animales , Especies en Peligro de Extinción , Biodiversidad , Variación Genética