Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 63
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Integr Zool ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38597117

RESUMEN

Golden snub-nosed monkeys show inconsistent frequency of placentophagy between wild and captive populations, with almost all births in the wild but around half of the births in captivity accompanied by the female's consumption of placenta. This aligns with nutritional demands-driven placentophagy, as captive populations are generally under less nutritional constraints for breeding females than the wild population. Placentophagy is probably adaptive in the wild and under positive selection due to nutritional benefits to both mothers and infants.

3.
Foods ; 12(7)2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-37048359

RESUMEN

Apiculture has been greatly developed in recent years in China. Beekeeping cooperatives and honey manufacturing enterprises have increased rapidly. As a result, a variety of honey products have entered the market, adding vitality to the food economy; however, the adulteration of honey products is on the rise in China. Previous attempts to control the adulteration of honey products mostly relied on technical, product-specific measures, and there was a lack of modeling research to guide the supervision of the honey product industry. In order to help local governments to better control the adulteration of honey products from a management perspective, this paper establishes an evolutionary game model composed of beekeeping cooperatives, honey product enterprises, and local governments. Through stability analysis and model simulation, we found that local government subsidies to cooperatives have little impact on the game system. Local government penalties to cooperatives and price adjustments of unadulterated raw honey by cooperatives are effective management tools to reduce the adulteration behavior of cooperatives. Local government penalties for enterprises are an effective management tool to reduce the adulteration behavior of enterprises. This research provides useful information for government agencies to design appropriate policies/business modes so as to promote sustainability and the healthy development of the honey product industry in China.

4.
Mol Ecol ; 32(12): 3239-3256, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36942819

RESUMEN

Genes of the major histocompatibility complex (MHC) play important roles in vertebrate immunocompetence. MHC genes thus offer females indirect benefits to mate choice through the production of offspring of an optimal MHC genotype. Females may choose males with specific MHC haplotypes, dissimilar MHC genotypes, MHC heterozygous males or MHC-diverse males. We tested these four alternatives for both female social and paternal choice in wild golden snub-nosed monkeys (Rhinopithecus roxellana) by examining overall genetic variability (via microsatellites) and four MHC-genes (DRB1, DRB2, DQA1 and DQB1). Monte Carlo randomization tests showed that MHC dissimilarity was favoured for social choice (males to which females were socially affiliated) and intermediate MHC dissimilarity was favoured in paternal choice (fathers of offspring). No evidence of inbreeding avoidance was found for either social or paternal mates. We found that MHC heterozygotes, higher microsatellite multilocus heterozygosity and higher microsatellites diversity were favoured for social mates, and higher microsatellite diversity was favoured for paternal mates. Independent of male age, we found that the formation of male-female social pairings is significantly predicted by compatibility based on the sharing of MHC haplotypes. However, we found no evidence of independent genetic effects on the duration of male-female social pairings, male social status (achieving OMU leader male status or not), the number of females with which individual leader males paired, the likelihood of potential male-female pairings producing offspring, or whether males fathered offspring or not. Overall, our findings suggest different genetic factors are involved in social and paternal choice in R. roxellana.


Asunto(s)
Colobinae , Presbytini , Animales , Masculino , Femenino , Presbytini/genética , Colobinae/genética , Genotipo , Complejo Mayor de Histocompatibilidad/genética
5.
Lancet Respir Med ; 11(12): 1051-1063, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36958364

RESUMEN

BACKGROUND: The complement pathway is a potential target for the treatment of severe COVID-19. We evaluated the safety and efficacy of ravulizumab, a terminal complement C5 inhibitor, in patients hospitalised with severe COVID-19 requiring invasive or non-invasive mechanical ventilation. METHODS: This phase 3, multicentre, open-label, randomised controlled trial (ALXN1210-COV-305) enrolled adult patients (aged ≥18 years) from 31 hospitals in France, Japan, Spain, the UK, and the USA. Eligible patients had a confirmed diagnosis of SARS-CoV-2 that required hospitalisation and either invasive or non-invasive mechanical ventilation, with severe pneumonia, acute lung injury, or acute respiratory distress syndrome confirmed by CT scan or x-ray. We randomly assigned participants (2:1) to receive intravenous ravulizumab plus best supportive care (BSC) or BSC alone using a web-based interactive response system. Randomisation was in permuted blocks of six with stratification by intubation status. Bodyweight-based intravenous doses of ravulizumab were administered on days 1, 5, 10, and 15. The primary efficacy endpoint was survival based on all-cause mortality at day 29 in the intention-to-treat (ITT) population. Safety endpoints were analysed in all randomly assigned patients in the ravulizumab plus BSC group who received at least one dose of ravulizumab, and in all randomly assigned patients in the BSC group. The trial is registered with ClinicalTrials.gov, NCT04369469, and was terminated at interim analysis due to futility. FINDINGS: Between May 10, 2020, and Jan 13, 2021, 202 patients were enrolled in the study and randomly assigned to ravulizumab plus BSC or BSC. 201 patients were included in the ITT population (135 in the ravulizumab plus BSC group and 66 in the BSC group). The ravulizumab plus BSC group comprised 96 (71%) men and 39 (29%) women with a mean age of 63·2 years (SD 13·23); the BSC group comprised 43 (65%) men and 23 (35%) women with a mean age of 63·5 years (12·40). Most patients (113 [84%] of 135 in the ravulizumab plus BSC group and 53 [80%] of 66 in the BSC group) were on invasive mechanical ventilation at baseline. Overall survival estimates based on multiple imputation were 58% for patients receiving ravulizumab plus BSC and 60% for patients receiving BSC (Mantel-Haenszel analysis: risk difference -0·0205; 95% CI -0·1703 to 0·1293; one-sided p=0·61). In the safety population, 113 (89%) of 127 patients in the ravulizumab plus BSC group and 56 (84%) of 67 in the BSC group had a treatment-emergent adverse event. Of these events, infections and infestations (73 [57%] vs 24 [36%] patients) and vascular disorders (39 [31%] vs 12 [18%]) were observed more frequently in the ravulizumab plus BSC group than in the BSC group. Five patients had serious adverse events considered to be related to ravulizumab. These events were bacteraemia, thrombocytopenia, oesophageal haemorrhage, cryptococcal pneumonia, and pyrexia (in one patient each). INTERPRETATION: Addition of ravulizumab to BSC did not improve survival or other secondary outcomes. Safety findings were consistent with the known safety profile of ravulizumab in its approved indications. Despite the lack of efficacy, the study adds value for future research into complement therapeutics in critical illnesses by showing that C5 inhibition can be accomplished in severely ill patients. FUNDING: Alexion, AstraZeneca Rare Disease.


Asunto(s)
COVID-19 , Neumonía , Masculino , Adulto , Humanos , Femenino , Adolescente , Persona de Mediana Edad , SARS-CoV-2 , Respiración Artificial , Resultado del Tratamiento
6.
iScience ; 26(2): 106098, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36852160

RESUMEN

Tactical deception can be beneficial for social animals during intra-specific competition. However, the use of tactical deception in wild mammals is predicted to be rare. We tested whether a food-provisioned free-ranging band of golden snub-nosed monkeys (Rhinopithecus roxellana) use alarm calls in a functionally deceptive manner to gain access to food resources, whether the rate of deceptive alarm calls varies among individuals, and whether there are any counter-deception behaviors. We used a hexagonal camera array consisting of 10 cameras to record videos during feeding, which allowed us to identify individual alarm callers. We found evidence that these monkeys use deceptive alarms and that adult females were more likely to use such calls than other individuals. The monkeys increased their rates of response to alarm calls when competition for food was high. However, we found no direct evidence of any counter-deception strategies.

7.
Mol Ecol Resour ; 2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36458971

RESUMEN

Polyploids are cells or organisms with a genome consisting of more than two sets of homologous chromosomes. Polyploid plants have important traits that facilitate speciation and are thus often model systems for evolutionary, molecular ecology and agricultural studies. However, due to their unusual mode of inheritance and double-reduction, diploid models of population genetic analysis cannot properly be applied to autopolyploids. To overcome this problem, we developed a software package entitled vcfpop to perform a variety of population genetic analyses for autopolyploids, such as parentage analysis, analysis of molecular variance, principal coordinates analysis, hierarchical clustering analysis and Bayesian clustering. We used three data sets to evaluate the capability of vcfpop to analyse large data sets on a desktop computer. This software is freely available at http://github.com/huangkang1987/vcfpop.

8.
Am J Reprod Immunol ; 88(2): e13559, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35514201

RESUMEN

PROBLEM: We evaluated eculizumab, a complement protein C5 inhibitor, for treatment of severe COVID-19 in pregnant and postpartum individuals. METHOD OF STUDY: Protocol ECU-COV-401 (clinicaltrials.gov NCT04355494) is an open label, multicenter, Expanded Access Program (EAP), evaluating eculizumab for treatment of severe COVID-19. Participants enrolled at our center from August 2020 to February 2021. Hospitalized patients were eligible if they had severe COVID-19 with bilateral pulmonary infiltrates and oxygen requirement. Eculizumab was administered on day 1 (1200 mg IV) with additional doses if still hospitalized (1200 mg IV on Days 4 and 8; 900 mg IV on Days 15 and 22; optional doses on Days 12 and 18). The primary outcome was survival at Day 15. Secondary outcomes included survival at Day 29, need for mechanical ventilation, and duration of hospital stay. We evaluated pharmacokinetic and pharmacodynamic data, safety, and adverse outcomes. RESULTS: Eight participants were enrolled at the Cedars-Sinai Medical Center, six during pregnancy (mean 30 ± 4.0 weeks) and two in the postpartum period. Baseline oxygen requirement ranged from 2 L/min nasal cannula to 12 L/min by non-rebreather mask. The median number of doses of eculizumab was 2 (range 1-3); the median time to hospital discharge was 5.5 days (range 3-12). All participants met the primary outcome of survival at Day 15, and all were alive and free of mechanical ventilation at Day 29. In three participants we demonstrated that free C5 and soluble C5b-9 levels decreased following treatment. There were no serious adverse maternal or neonatal events attributed to eculizumab at 3 months. CONCLUSION: We describe use of eculizumab to treat severe COVID-19 in a small series of pregnant and postpartum adults. A larger, controlled study in pregnancy is indicated.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Tratamiento Farmacológico de COVID-19 , Adulto , Anticuerpos Monoclonales Humanizados/uso terapéutico , Proteínas del Sistema Complemento , Femenino , Humanos , Recién Nacido , Oxígeno , Embarazo , SARS-CoV-2 , Resultado del Tratamiento
9.
Innovation (Camb) ; 3(2): 100207, 2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35243466

RESUMEN

In mammal herbivores, fiber digestion usually occurs predominantly in either the foregut or the hindgut. Reports of mechanisms showing synergistic function in both gut regions for the digestion of fiber and other nutrients in wild mammals are rare because it requires integrative study of anatomy, physiology, and gut microbiome. Colobine monkeys (Colobinae) are folivorous, with high-fiber foods fermented primarily in their foreguts. A few colobine species live in temperate regions, so obtaining energy from fiber during the winter is essential. However, the mechanisms enabling this remain largely unknown. We hypothesized that such species possess specialized mechanisms to enhance fiber digestion in the hindgut and studied microbial and morphological digestive adaptations of golden snub-nosed monkeys (GSMs), Rhinopithecus roxellana. which is a temperate forest colobine from central China that experiences high-thermal-energy demands while restricted to a fibrous, low-energy winter diet. We tested for synergistic foregut and hindgut fiber digestion using comparisons of morphology, microbiome composition and function, and digestive efficiency. We found that the GSM colon has a significantly greater volume than that of other foregut-fermenting colobines. The microbiomes of the foregut and hindgut differed significantly in composition and abundance. However, while digestive efficiency and the expression of microbial gene functions for fiber digestion were higher in the foregut than in the hindgut, both gut regions were dominated by microbial taxa producing enzymes to enable active digestion of complex carbohydrates. Our data suggest that both the GSM foregut and hindgut facilitate fiber digestion and that an enlarged colon is likely an adaptation to accommodate high throughput of fiber-rich food during winter.

10.
Heredity (Edinb) ; 128(1): 11-20, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34983965

RESUMEN

Linkage disequilibrium (LD) is the non-random association of alleles at different loci. Squared LD coefficients r2 (for phased genotypes) and [Formula: see text] (for unphased genotypes) will converge to constants that are determined by the sample size, the recombination frequency, the effective population size and the mating system. LD can therefore be used for gene mapping and the estimation of effective population size. However, current methods work only with diploids. To resolve this problem, we here extend the linkage disequilibrium measures to include polysomic inheritance. We derive the values of r2 and [Formula: see text] at equilibrium state for various mating systems and different ploidy levels. For unlinked loci, [Formula: see text] for monoecious and dioecious (with random pairing) mating systems or [Formula: see text] for dioecious mating systems (with lifetime pairing), where f is the number of females in a half-sib family and η is a constant related to the ploidy level. We simulate the application of estimating Ne using unphased genotypes. We find that estimating Ne in polyploids requires similar sample sizes and numbers of loci as in diploids, with the main source of bias due to using 0.5 as the recombination frequency.


Asunto(s)
Genética de Población , Modelos Genéticos , Genotipo , Desequilibrio de Ligamiento , Densidad de Población
11.
Nat Ecol Evol ; 5(7): 974-986, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34002050

RESUMEN

Many insects metamorphose from antagonistic larvae into mutualistic adult pollinators, with reciprocal adaptation leading to specialized insect-plant associations. It remains unknown how such interactions are established at molecular level. Here we assemble high-quality genomes of a fig species, Ficus pumila var. pumila, and its specific pollinating wasp, Wiebesia pumilae. We combine multi-omics with validation experiments to reveal molecular mechanisms underlying this specialized interaction. In the plant, we identify the specific compound attracting pollinators and validate the function of several key genes regulating its biosynthesis. In the pollinator, we find a highly reduced number of odorant-binding protein genes and an odorant-binding protein mainly binding the attractant. During antagonistic interaction, we find similar chemical profiles and turnovers throughout the development of galled ovules and seeds, and a significant contraction of detoxification-related gene families in the pollinator. Our study identifies some key genes bridging coevolved mutualists, establishing expectations for more diffuse insect-pollinator systems.


Asunto(s)
Ficus , Avispas , Adaptación Fisiológica , Animales , Humanos , Polinización , Simbiosis
12.
G3 (Bethesda) ; 11(2)2021 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-33585871

RESUMEN

Polyploidy poses several problems for parentage analysis. We present a new polysomic inheritance model for parentage analysis based on genotypes or allelic phenotypes to solve these problems. The effects of five factors are simultaneously accommodated in this model: (1) double-reduction, (2) null alleles, (3) negative amplification, (4) genotyping errors and (5) self-fertilization. To solve genotyping ambiguity (unknown allele dosage), we developed a new method to establish the likelihood formulas for allelic phenotype data and to simultaneously include the effects of our five chosen factors. We then evaluated and compared the performance of our new method with three established methods by using both simulated data and empirical data from the cultivated blueberry (Vaccinium corymbosum). We also developed and compared the performance of two additional estimators to estimate the genotyping error rate and the sample rate. We make our new methods freely available in the software package polygene, at http://github.com/huangkang1987/polygene.


Asunto(s)
Poliploidía , Programas Informáticos , Alelos , Arándanos Azules (Planta) , Genotipo , Fenotipo
13.
Integr Zool ; 16(2): 202-213, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32961032

RESUMEN

Both natural conditions and anthropogenic factors affect the survivability, distribution, and population density of wildlife. To understand the extent and how these factors drive species distributions, a detailed description of animal movement patterns in natural habitats is needed. In this study, we used satellite telemetry to monitor elevational ranges favored by endangered golden snub-nosed monkeys (Rhinopithecus roxellana), in the Qinling Mountains, central China. We investigated the abundance and distribution of food resources through sampling vegetation quadrats at different elevations and sampled anthropogenic activities using field surveys. Our results indicated that although there was no significant variation in food resources between low- (<1500 m) and middle-elevations (1500-2200 m), monkeys were found most often in areas above 1500 m, where there was less anthropogenic development (e.g. houses and roads); however, monkeys rarely ranged above 2200 m and had limited food availability at this altitude. There was limited human disturbance at this elevation. We suggest that both human activity and ecological constraints (i.e. food resources) have considerable effects on elevational use of R. roxellana in the Qinling Mountains. This study highlights the critical roles these factors can play in shaping the vertical distribution of high-altitude primates. This research provides useful insights for habitat-based conservation plans in which human disturbance management and habitat restoration should be prioritized.


Asunto(s)
Altitud , Distribución Animal/fisiología , Colobinae/fisiología , Actividades Humanas , Animales , China , Femenino , Alimentos , Masculino , Tecnología de Sensores Remotos
14.
Integr Zool ; 16(1): 33-52, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32648364

RESUMEN

The analysis of molecular variance (AMOVA) is a widely used statistical method in population genetics and molecular ecology. The classic framework of AMOVA only supports haploid and diploid data, in which the number of hierarchies ranges from two to four. In practice, natural populations can be classified into more hierarchies, and polyploidy is frequently observed in extant species. The ploidy level may even vary within the same species, and/or within the same individual. We generalized the framework of AMOVA such that it can be used for any number of hierarchies and any level of ploidy. Based on this framework, we present four methods to account for data that are multilocus genotypic and allelic phenotypic (with unknown allele dosage). We use simulated datasets and an empirical dataset to evaluate the performance of our framework. We make freely available our methods in a new software package, polygene, which is freely available at https://github.com/huangkang1987/polygene.


Asunto(s)
Análisis de Varianza , Técnicas Genéticas , Ploidias , Genética de Población , Programas Informáticos
15.
Am J Phys Anthropol ; 173(4): 630-642, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32918292

RESUMEN

OBJECTIVES: Social animals often have dominance hierarchies, with high rank conferring preferential access to resources. In primates, competition among males is often assumed to occur predominantly over reproductive opportunities. However, competition for food may occur during food shortages, such as in temperate species during winter. Higher-ranked males may thus gain preferential access to high-profitability food, which would enable them to spend longer engaged in activities other than feeding. MATERIALS AND METHODS: We performed a field experiment with a breeding band of golden snub-nosed monkeys, a species that lives in a multi-level society in high-altitude forests in central China. We provisioned monkey's high-profitability food during winter when natural foods are limited, and then recorded the times individual adult males spent engaged in different behaviors. RESULTS: Higher-ranking males spent less time feeding overall and fed on provisioned foods at a higher rate than lower-ranking males. Higher-ranking males therefore had more time to spend on alternative behaviors. We found no significant difference according to rank in times spent moving or resting. However, high-ranking males spend significantly longer on affiliative behaviors with other members of their social sub-units, especially grooming and being groomed, behaviors known to promote social cohesion in primates. DISCUSSION: We show that preferential access to high-profitability foods likely relaxes time-budget constraints to higher-ranking males. High-ranking males thus spend more time on non-feeding activities, especially grooming, which may enhance social cohesion within their social sub-unit. We discuss the potential direct and indirect benefits to high-ranking males associated with preferential access to high-value food during winter.


Asunto(s)
Colobinae/fisiología , Conducta Competitiva/fisiología , Conducta Alimentaria/fisiología , Predominio Social , Animales , Antropología Física , China , Femenino , Aseo Animal/fisiología , Masculino
16.
Front Genet ; 11: 609414, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33408742

RESUMEN

The genes of the major histocompatibility complex (MHC) are an important component of the vertebrate immune system and play a significant role in mate choice in many species. However, it remains unclear whether female mate choice in non-human primates is based on specific functional genes and/or genome-wide genes. The golden snub-nosed monkey (Rhinopithecus roxellana) lives in a multilevel society, which consists of several polygynous one-male-several-female units. Although adult females tend to mainly socialize with one adult male, females often initiate extra-pair copulations with other males resulting in a high proportion of offspring being fathered by extra-pair males. We investigated the effects of adaptive MHC genes and neutral microsatellites on female mate choice in a wild R. roxellana population. We sequenced 54 parent-offspring triads using two MHC class II loci (Rhro-DQA1 and Rhro-DQB1) and 20 microsatellites from 3 years of data. We found that the paternities of offspring were non-randomly associated with male MHC compositions not microsatellite genotypes. Our study showed that the fathers of all infants had significantly less variance for several estimates of genetic similarity to the mothers compared with random males at both MHC loci. Additionally, the MHC diversity of these fathers was significantly higher than random males. We also found support for choice based on specific alleles; compared with random males, Rhro-DQA1∗ 05 and Rhro-DQB1∗ 08 were more common in both the OMU (one-male unit) males and the genetic fathers of offspring. This study provides new evidence for female mate choice for MHC-intermediate dissimilarity (rather than maximal MHC dissimilarity) and highlights the importance of incorporating multiple MHC loci and social structure into studies of MHC-based mate choice in non-human primates.

17.
J Evol Biol ; 33(3): 366-376, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31747079

RESUMEN

Fig-pollinating wasps (Agaonidae) only reproduce within fig tree inflorescences (figs). Agaonid offspring sex ratios are usually female-biased and often concur with local mate competition theory (LMC). LMC predicts less female-bias when several foundresses reproduce in a fig due to reduced relatedness among intra-sexually competing male offspring. Clutch size, the offspring produced by each foundress, is a strong predictor of agaonid sex ratios and correlates negatively with foundress number. However, clutch size variation can result from several processes including egg load (eggs within a foundress), competition among foundresses and oviposition site limitation, each of which can be used as a sex allocation cue. We introduced into individual Ficus racemosa figs single Ceratosolen fusciceps foundresses and allowed each to oviposit from zero to five hours thus variably reducing their eggs-loads and then introduced each wasp individually into a second fig. Offspring sex ratio (proportion males) in second figs correlated negatively with clutch size, with males produced even in very small clutches. Ceratosolen fusciceps lay mainly male eggs first and then female eggs. Our results demonstrate that foundresses do not generally lay or attempt to lay a 'fixed' number of males, but do 'reset to zero' their sex allocation strategy on entering a second fig. With decreasing clutch size, gall failure increased, probably due to reduced pollen. We conclude that C. fusciceps foundresses can use their own egg loads as a cue to facultatively adjust their offspring sex ratios and that foundresses may also produce more 'insurance' males when they can predict increasing rates of offspring mortality.


Asunto(s)
Tamaño de la Nidada/fisiología , Razón de Masculinidad , Avispas/fisiología , Animales , Femenino , Masculino , Reproducción/fisiología , Factores de Tiempo
18.
Mol Ecol Resour ; 19(5): 1218-1229, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31070300

RESUMEN

A significant portion of plant species are polyploids, with ploidy levels sometimes varying among individuals and/or populations. Current techniques to determine the individual ploidy, e.g., flow cytometry, chromosome counting or genotyping-by-sequencing, are often cumbersome. Based on the genotypic probabilities for polysomic inheritance under double-reduction, we developed a model to estimate allele frequency and infer the ploidy status of individuals from the allelic phenotypes of codominant genetic markers. The allele frequencies are estimated by an expectation-maximization algorithm in the presence of null alleles, false alleles, negative amplifications and self-fertilization, and the posterior probabilities are used to assign individuals into different levels of ploidy. The accuracy of this method under different conditions is evaluated. Our methods are freely available in a new software package, ploidyinfer, for use by other researchers which can be downloaded from http://github.com/huangkang1987/ploidyinfer.


Asunto(s)
Técnicas de Genotipaje/métodos , Fenotipo , Plantas/genética , Ploidias , Dosificación de Gen , Frecuencia de los Genes , Genotipo
19.
Mol Ecol Resour ; 19(5): 1240-1253, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31094065

RESUMEN

Duplicated loci, for example those associated with major histocompatibility complex (MHC) genes, often have similar DNA sequences that can be coamplified with a pair of primers. This results in genotyping difficulties and inaccurate analyses. Here, we present a method to assign alleles to different loci in amplifications of duplicated loci. This method simultaneously considers several factors that may each affect correct allele assignment. These are the sharing of identical alleles among loci, null alleles, copy number variation, negative amplification, heterozygote excess or heterozygote deficiency, and linkage disequilibrium. The possible multilocus genotypes are extracted from the alleles for each individual and weighted to estimate the allele frequencies. The likelihood of an allele configuration is calculated and is optimized with a heuristic algorithm. Monte-Carlo simulations and three empirical MHC data sets are used as examples to evaluate the efficacy of our method under different conditions. Our new software, mhc-typer V1.1, is freely available at https://github.com/huangkang1987/mhc-typer.


Asunto(s)
Alelos , Biología Computacional/métodos , Duplicación de Gen , Sitios Genéticos , Genotipo , Programas Informáticos
20.
Appl Plant Sci ; 7(5): e01244, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31139510

RESUMEN

PREMISE: Rosebay willowherb, or fireweed (Chamerion angustifolium: Onagraceae), has diploid, tetraploid, and hexaploid cytotypes. There are known physiological and ecological differences among the three cytotypes, but genetic differences remain undetermined. We developed simple sequence repeat (SSR) markers for this species. METHODS AND RESULTS: Leaf samples were collected from three hexaploid C. angustifolium populations. We successfully amplified 16 SSR loci, which were found to be highly polymorphic. The number of alleles, the observed heterozygosity levels, and the expected heterozygosity levels ranged from four to 13, 0.286-0.899, and 0.372-0.871, respectively. Most primers could also be amplified successfully in C. conspersum and the closely related species Epilobium palustre. CONCLUSIONS: The 16 polymorphic SSR markers developed here will be useful for genetic studies in C. angustifolium and related species.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...