Low-density genotype panel for both parentage verification and discovery in a multi-breed sheep population

peer-reviewedThe generally low usage of artificial insemination and single-sire mating in sheep, compounded by mob lambing (and lambing outdoors), implies that parentage assignment in sheep is challenging. The objective here was to develop a low-density panel of single nucleotide polymorphisms (SNPs) for accurate parentage verification and discovery in sheep. Of particular interest was where SNP selection was limited to only a subset of chromosomes, thereby eliminating the ability to accurately impute genome-wide denser marker panels. Data used consisted of 10,933 candidate SNPs on 9,390 purebred sheep. These data consisted of 1,876 validated genotyped sire–offspring pairs and 2,784 validated genotyped dam–offspring pairs. The SNP panels developed consisted of 87 SNPs to 500 SNPs. Parentage verification and discovery were undertaken using 1) exclusion, based on the sharing of at least one allele between candidate parent–offspring pairs, and 2) a likelihood-based approach. Based on exclusion, allowing for one discordant offspring–parent genotype, a minimum of 350 SNPs was required when the goal was to unambiguously identify the true sire or dam from all possible candidates. Results suggest that, if selecting SNPs across the entire genome, a minimum of 250 carefully selected SNPs are required to ensure that the most likely selected parent (based on the likelihood approach) was, in fact, the true parent. If restricting the SNPs to just a subset of chromosomes, the recommendation is to use at least a 300-SNP panel from at least six chromosomes, with approximately an equal number of SNPs per chromosome

Principled Parentage: Abandoning the Gender-Based Underpinnings of Legal Parentage Analysis as Applied in the Context of Gestational Surrogacy

While reproductive technology has provided new options for women who want children, our legal understanding of parentage is still informed by the traditional conception model of two parents: one male and one female. A parent who both is a biological parent and has developed a parent-child relationship with a genetic child ought to be considered a legal parent as well. This conclusion ought not to be vulnerable to attack based on the gender of the other parent; rather, each parent’s claims should be evaluated independently. When gender becomes irrelevant and we abandon the gender-based underpinnings of legal parentage analysis as applied in gestational surrogacy cases, correct parentage decisions can be more easily reached when considering families created by non-traditional means

Structure of unstable light nuclei

The structure of light nuclei out to the drip lines and beyond up to Z = 8 is interpreted in terms of the shell model. Special emphasis is given to the underlying supermultiplet symmetry of the p-shell nuclei which form cores for neutrons and protons added in sd-shell orbits. Detailed results are given on the wave functions, widths, and Coulomb energy shifts for a wide range of non-normal parity states in the p-shell.Comment: 21 pages, to appear in Nuclear Physics

Patterns, causes, and consequences of marine larval dispersal

Quantifying the probability of larval exchange among marine populations is key to predicting local population dynamics and optimizing networks of marine protected areas. The pattern of connectivity among populations can be described by the measurement of a dispersal kernel. However, a statistically robust, empirical dispersal kernel has been lacking for any marine species. Here, we use genetic parentage analysis to quantify a dispersal kernel for the reef fish Elacatinus lori, demonstrating that dispersal declines exponentially with distance. The spatial scale of dispersal is an order of magnitude less than previous estimates—the median dispersal distance is just 1.7 km and no dispersal events exceed 16.4 km despite intensive sampling out to 30 km from source. Overlaid on this strong pattern is subtle spatial variation, but neither pelagic larval duration nor direction is associated with the probability of successful dispersal. Given the strong relationship between distance and dispersal, we show that distance-driven logistic models have strong power to predict dispersal probabilities. Moreover, connectivity matrices generated from these models are congruent with empirical estimates of spatial genetic structure, suggesting that the pattern of dispersal we uncovered reflects long-term patterns of gene flow. These results challenge assumptions regarding the spatial scale and presumed predictors of marine population connectivity. We conclude that if marine reserve networks aim to connect whole communities of fishes and conserve biodiversity broadly, then reserves that are close in space (<10 km) will accommodate those members of the community that are short-distance dispersers.We thank Diana Acosta, Alben David, Kevin David, Alissa Rickborn, and Derek Scolaro for assistance with field work; Eliana Bondra for assistance with molecular work; and Peter Carlson for assistance with otolith work. We are grateful to Noel Anderson, David Lindo, Claire Paris, Robert Warner, Colleen Webb, and two anonymous reviewers for comments on this manuscript. This work was supported by National Science Foundation (NSF) Grant OCE-1260424, and C.C.D. was supported by NSF Graduate Research Fellowship DGE-1247312. All work was approved by Belize Fisheries and Boston University Institutional Animal Care and Use Committee. (OCE-1260424 - National Science Foundation (NSF); DGE-1247312 - NSF Graduate Research Fellowship)Published versio

Assessing the identity of the variety "Pedro Giménez" grown in Argentina through the use of microsatellite markers.

'Pedro Giménez' es una variedad criolla blanca cultivada en Argentina, principalmente en las provincias de Mendoza y San Juan, siendo la variedad con la mayor superficie entre las uvas blancas de vinificación. Su origen es desconocido, como también su relación con la variedad española 'Pedro Ximénez', cultivada especialmente en la región de Jerez, España. En trabajos previos se ha probado que la mayoría de las variedades criollas existentes en América se habrían originado del cruzamiento de 'Moscatel de Alejandría' x 'Criolla Chica'. El presente trabajo tuvo como objetivos comparar las variedades 'Pedro Giménez' y 'Pedro Ximénez', y establecer relaciones de parentesco con 'Moscatel de Alejandría' y 'Criolla Chica'. Se utilizaron 18 loci microsatélites nucleares y 3 loci microsatélites de cloroplasto. 'Pedro Giménez' compartió sólo el 38% de los alelos con 'Pedro Ximénez', por lo que se pudo inferir que se trata de variedades diferentes. En todos los loci polimórficos nucleares analizados 'Pedro Giménez' compartió uno de los alelos con 'Moscatel de Alejandría' y el otro con 'Criolla Chica'. Estos datos, junto con el resultado del análisis de SSR de cloroplastos, avalan la hipótesis que, como muchas de las variedades criollas, 'Pedro Giménez' sería fruto del cruzamiento entre estos dos progenitores, siendo 'Criolla Chica' probablemente el progenitor materno.´Pedro Giménez´ is a white criolla variety cropped in Argentina, mainly in Mendoza and San Juan, being the most planted white variety destined for wine making in the country. Its origin remains unknown, as well as its relationship with Spanish variety ´Pedro Ximénez´, mostly grown in Jerez, Spain. Previous works have probed that most of Criollas varieties existing in America at the moment, are the offspring of ´Muscat of Alexandria´ x ´Criolla Chica´. The aim of the present work was to compare ´Pedro Giménez´ with the Spanish variety ´Pedro Ximénez´, and to establish its degree of relatedness to ´Muscat of Alexandria´ and ´Criolla Chica´. Therefore we used a set of 18 nuclear SSR loci and 3 chloroplast SSR loci. ´Pedro Giménez´ shared only 38% of the alleles under analysis with ´Pedro Ximénez´, indicating that they are indeed two different varieties. In all 18 polymorphic nuclear SSR loci ´Pedro Giménez´ shared 50% of its alleles with ´Muscat of Alexandria´, while the other 50% of the alleles present in ´Pedro Giménez´ were also present in ´Criolla Chica´. This data, along with those from the chloroplast SSR analysis, strongly suggest that ´Pedro Giménez´ is the progeny of ´Muscat of Alexandria´ x ´Criolla Chica´, being the latest one the most likely female progenitor.Fil: Duran, Martin Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Agüero, Cecilia B.. University of California at Davis; Estados UnidosFil: Martínez, Liliana Estela. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Departamento de Ciencias Biológicas. Cátedra de Fisiología Vegetal; Argentin

Pre-school enrollment: an analysis by immigrant generation

There has been minimal research on the pre-school enrollment of immigrant children. Using 1990 U.S. Census data, this paper investigates pre-school enrollment of child immigrants, those who immigrated as children and the U.S.-born children of immigrants. The analysis is conducted using probit analysis. Pre-school enrollment is found to vary systematically with parental characteristics (income and education), immigrant generation, number of siblings, mother’s labor supply and country of origin. Among the foreign-born, differences in pre-school enrollment are analyzed by country of origin. Among the U.S.-born children of immigrants pre-school enrollment is greatest among those with both parents foreign born

The consequences of feminization in breeding groups of wild fish

EHP is a publication of the U.S. government. Publication of EHP lies in the public domain and is therefore without copyright. Research articles from EHP may be used freely; however, articles from the News section of EHP may contain photographs or figures copyrighted by other commercial organizations and individuals that may not be used without obtaining prior approval from both the EHP editors and the holder of the copyright. Use of any materials published in EHP should be acknowledged (for example, "Reproduced with permission from Environmental Health Perspectives") and a reference provided for the article from which the material was reproduced.BACKGROUND: The feminization of nature by endocrine-disrupting chemicals (EDCs) is a key environmental issue affecting both terrestrial and aquatic wildlife. A crucial and as yet unanswered question is whether EDCs have adverse impacts on the sustainability of wildlife populations. There is widespread concern that intersex fish are reproductively compromised, with potential population-level consequences. However, to date, only in vitro sperm quality data are available in support of this hypothesis. OBJECTIVE: The aim of this study was to examine whether wild endocrine-disrupted fish can compete successfully in a realistic breeding scenario. METHODS: In two competitive breeding experiments using wild roach (Rutilus rutilus), we used DNA microsatellites to assign parentage and thus determine reproductive success of the adults. RESULTS: In both studies, the majority of intersex fish were able to breed, albeit with varying degrees of success. In the first study, where most intersex fish were only mildly feminized, body length was the only factor correlated with reproductive success. In the second study, which included a higher number of more severely intersex fish, reproductive performance was negatively correlated with severity of intersex. The intersex condition reduced reproductive performance by up to 76% for the most feminized individuals in this study, demonstrating a significant adverse effect of intersex on reproductive performance. CONCLUSION: Feminization of male fish is likely to be an important determinant of reproductive performance in rivers where there is a high prevalence of moderately to severely feminized males.Funding for this work was derived through the Endocrine Disruption in Catchments project, which was supported by the U.K. Department for Environment Food and Rural Affairs and the U.K. Environment Agency